[Title 49 CFR ]
[Code of Federal Regulations (annual edition) - October 1, 2012 Edition]
[From the U.S. Government Printing Office]



[[Page i]]

          

          Title 49

Transportation


________________________

Parts 178 to 199

                         Revised as of October 1, 2012

          Containing a codification of documents of general 
          applicability and future effect

          As of October 1, 2012
                    Published by the Office of the Federal Register 
                    National Archives and Records Administration as a 
                    Special Edition of the Federal Register

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                            Table of Contents



                                                                    Page
  Explanation.................................................       v

  Title 49:
    SUBTITLE B--Other Regulations Relating to Transportation 
      (Continued)
          Chapter I--Pipeline and Hazardous Materials Safety 
          Administration, Department of Transportation 
          (Continued)                                                5
  Finding Aids:
      Table of CFR Titles and Chapters........................     637
      Alphabetical List of Agencies Appearing in the CFR......     657
      List of CFR Sections Affected...........................     667

[[Page iv]]





                     ----------------------------

                     Cite this Code: CFR
                     To cite the regulations in 
                       this volume use title, 
                       part and section number. 
                       Thus, 49 CFR 178.1 refers 
                       to title 49, part 178, 
                       section 1.

                     ----------------------------

[[Page v]]



                               EXPLANATION

    The Code of Federal Regulations is a codification of the general and 
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parts covering specific regulatory areas.
    Each volume of the Code is revised at least once each calendar year 
and issued on a quarterly basis approximately as follows:

Title 1 through Title 16.................................as of January 1
Title 17 through Title 27..................................as of April 1
Title 28 through Title 41...................................as of July 1
Title 42 through Title 50................................as of October 1

    The appropriate revision date is printed on the cover of each 
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LEGAL STATUS

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HOW TO USE THE CODE OF FEDERAL REGULATIONS

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[[Page vi]]

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[[Page vii]]

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    October 1, 2012.







[[Page ix]]



                               THIS TITLE

    Title 49--Transportation is composed of nine volumes. The parts in 
these volumes are arranged in the following order: Parts 1-99, parts 
100-177, parts 178-199, parts 200-299, parts 300-399, parts 400-571, 
parts 572-999, parts 1000-1199, and part 1200 to end. The first volume 
(parts 1-99) contains current regulations issued under subtitle A--
Office of the Secretary of Transportation; the second volume (parts 100-
177) and the third volume (parts 178-199) contain the current 
regulations issued under chapter I--Pipeline and Hazardous Materials 
Safety Administration (DOT); the fourth volume (parts 200-299) contains 
the current regulations issued under chapter II--Federal Railroad 
Administration (DOT); the fifth volume (parts 300-399) contains the 
current regulations issued under chapter III--Federal Motor Carrier 
Safety Administration (DOT); the sixth volume (parts 400-571) contains 
the current regulations issued under chapter IV--Coast Guard (DHS), and 
some of chapter V--National Highway Traffic Safety Administration (DOT); 
the seventh volume (parts 572-999) contains the rest of the regulations 
issued under chapter IV, and the current regulations issued under 
chapter VI--Federal Transit Administration (DOT), chapter VII--National 
Railroad Passenger Corporation (AMTRAK), and chapter VIII--National 
Transportation Safety Board; the eighth volume (parts 1000-1199) 
contains the current regulations issued under chapter X--Surface 
Transportation Board and the ninth volume (part 1200 to end) contains 
the current regulations issued under chapter X--Surface Transportation 
Board, chapter XI--Research and Innovative Technology Administration, 
and chapter XII--Transportation Security Administration, Department of 
Transportation. The contents of these volumes represent all current 
regulations codified under this title of the CFR as of October 1, 2012.

    In the volume containing parts 100-177, see Sec.  172.101 for the 
Hazardous Materials Table. The Federal Motor Vehicle Safety Standards 
appear in part 571.

    Redesignation tables for chapter III--Federal Motor Carrier Safety 
Administration, Department of Transportation and chapter XII--
Transportation Security Administration, Department of Transportation 
appear in the Finding Aids section of the fifth and ninth volumes.

    For this volume, Susannah C. Hurley was Chief Editor. The Code of 
Federal Regulations publication program is under the direction of 
Michael L. White, assisted by Ann Worley.

[[Page 1]]



                        TITLE 49--TRANSPORTATION




                  (This book contains parts 178 to 199)

  --------------------------------------------------------------------

  Editorial Note: Other regulations issued by the Department of 
Transportation appear in 14 CFR chapters I and II, 23 CFR, 33 CFR 
chapters I and IV, 44 CFR chapter IV, 46 CFR chapters I through III, 48 
CFR chapter 12, and 49 CFR chapters I through VI.

  SUBTITLE B--Other Regulations Relating to Transportation (Continued)

                                                                    Part

chapter I--Pipeline and Hazardous Materials Safety 
  Administration, Department of Transportation, DOT.........         178

[[Page 3]]

  Subtitle B--Other Regulations Relating to Transportation (Continued)

[[Page 5]]



   CHAPTER I--PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, 
                DEPARTMENT OF TRANSPORTATION (CONTINUED)




  --------------------------------------------------------------------

                      SUBCHAPTER D--PIPELINE SAFETY
Part                                                                Page
178             Specifications for packagings...............           7
179             Specifications for tank cars................         257
180             Continuing qualification and maintenance of 
                    packagings..............................         316
181-189         [Reserved]

190             Pipeline safety programs and rulemaking 
                    procedures..............................         377
191             Transportation of natural and other gas by 
                    pipeline; annual reports, incident 
                    reports, and safety-related condition 
                    reports.................................         398
192             Transportation of natural and other gas by 
                    pipeline: Minimum Federal safety 
                    standards...............................         404
193             Liquefied natural gas facilities: Federal 
                    safety standards........................         518
194             Response plans for onshore oil pipelines....         537
195             Transportation of hazardous liquids by 
                    pipeline................................         548
196-197         [Reserved]

198             Regulations for grants to aid State pipeline 
                    safety programs.........................         617
199             Drug and alcohol testing....................         620

[[Page 7]]



PART 178_SPECIFICATIONS FOR PACKAGINGS--Table of Contents



Sec.
178.1 Purpose and scope.
178.2 Applicability and responsibility.
178.3 Marking of packagings.

Subpart A [Reserved]

       Subpart B_Specifications for Inside Containers, and Linings

178.33 Specification 2P; inner nonrefillable metal receptacles.
178.33-1 Compliance.
178.33-2 Type and size.
178.33-3 Inspection.
178.33-4 Duties of inspector.
178.33-5 Material.
178.33-6 Manufacture.
178.33-7 Wall thickness.
178.33-8 Tests.
178.33-9 Marking.
178.33a Specification 2Q; inner nonrefillable metal receptacles.
178.33a-1 Compliance.
178.33a-2 Type and size.
178.33a-3 Inspection.
178.33a-4 Duties of inspector.
178.33a-5 Material.
178.33a-6 Manufacture.
178.33a-7 Wall thickness.
178.33a-8 Tests.
178.33a-9 Marking.
178.33b Specification 2S; inner nonrefillable plastic receptacles
178.33b-1 Compliance.
178.33b-2 Type and size.
178.33b-3 Inspection.
178.33b-4 Duties of inspector.
178.33b-5 Material.
178.33b-6 Manufacture.
178.33b-7 Design qualification test.
178.33b-8 Production tests.
178.33b-9 Marking.

                 Subpart C_Specifications for Cylinders

178.35 General requirements for specification cylinders.
178.36 Specification 3A and 3AX seamless steel cylinders.
178.37 Specification 3AA and 3AAX seamless steel cylinders.
178.38 Specification 3B seamless steel cylinders.
178.39 Specification 3BN seamless nickel cylinders.
178.42 Specification 3E seamless steel cylinders.
178.44 Specification 3HT seamless steel cylinders for aircraft use.
178.45 Specification 3T seamless steel cylinders.
178.46 Specification 3AL seamless aluminum cylinders.
178.47 Specification 4DS welded stainless steel cylinders for aircraft 
          use.
178.50 Specification 4B welded or brazed steel cylinders.
178.51 Specification 4BA welded or brazed steel cylinders.
178.53 Specification 4D welded steel cylinders for aircraft use.
178.55 Specification 4B240ET welded or brazed cylinders.
178.56 Specification 4AA480 welded steel cylinders.
178.57 Specification 4L welded insulated cylinders.
178.58 Specification 4DA welded steel cylinders for aircraft use.
178.59 Specification 8 steel cylinders with porous fillings for 
          acetylene.
178.60 Specification 8AL steel cylinders with porous fillings for 
          acetylene.
178.61 Specification 4BW welded steel cylinders with electric-arc welded 
          longitudinal seam.
178.65 Specification 39 non-reusable (non-refillable) cylinders.
178.68 Specification 4E welded aluminum cylinders.
178.69 Responsibilities and requirements for manufacturers of UN 
          pressure receptacles.
178.70 Approval of UN pressure receptacles.
178.71 Specifications for UN pressure receptacles.
178.74 Approval of MEGCs.
178.75 Specifications for MEGCs.

Appendix A to Subpart C of Part 178--Illustrations: Cylinder Tensile 
          Sample

Subparts D-G [Reserved]

               Subpart H_Specifications for Portable Tanks

178.251--178.253-5 [Reserved]
178.255 Specification 60; steel portable tanks.
178.255-1 General requirements.
178.255-2 Material.
178.255-3 Expansion domes.
178.255-4 Closures for manholes and domes.
178.255-5 Bottom discharge outlets.
178.255-6 Loading and unloading accessories.
178.255-7 Protection of valves and accessories.
178.255-8 Safety devices.
178.255-9 Compartments.
178.255-10 Lining.
178.255-11 Tank mountings.
178.255-12 Pressure test.
178.255-13 Repair of tanks.
178.255-14 Marking.
178.255-15 Report.
178.273 Approval of Specification UN portable tanks.
178.274 Specification for UN portable tanks.

[[Page 8]]

178.275 Specification for UN Portable Tanks intended for the 
          transportation of liquid and solid hazardous materials.
178.276 Requirements for the design, construction, inspection and 
          testing of portable tanks intended for the transportation of 
          non-refrigerated liquefied compressed gases.
178.277 Requirements for the design, construction, inspection and 
          testing of portable tanks intended for the transportation of 
          refrigerated liquefied gases.

Subpart I [Reserved]

Subpart J_Specifications for Containers for Motor Vehicle Transportation

178.318 Specification MC 201; container for detonators and percussion 
          caps.
178.318-1 Scope.
178.318-2 Container.
178.318-3 Marking.
178.320 General requirements applicable to all DOT specification cargo 
          tank motor vehicles.
178.337 Specification MC 331; cargo tank motor vehicle primarily for 
          transportation of compressed gases as defined in subpart G of 
          part 173 of this subchapter.
178.337-1 General requirements.
178.337-2 Material.
178.337-3 Structural integrity.
178.337-4 Joints.
178.337-5 Bulkheads, baffles and ring stiffeners.
178.337-6 Closure for manhole.
178.337-7 Overturn protection.
178.337-8 Openings, inlets and outlets.
178.337-9 Pressure relief devices, piping, valves, hoses, and fittings.
178.337-10 Accident damage protection.
178.337-11 Emergency discharge control.
178.337-12 [Reserved]
178.337-13 Supporting and anchoring.
178.337-14 Gauging devices.
178.337-15 Pumps and compressors.
178.337-16 Testing.
178.337-17 Marking.
178.337-18 Certification.
178.338 Specification MC-338; insulated cargo tank motor vehicle.
178.338-1 General requirements.
178.338-2 Material.
178.338-3 Structural integrity.
178.338-4 Joints.
178.338-5 Stiffening rings.
178.338-6 Manholes.
178.338-7 Openings.
178.338-8 Pressure relief devices, piping, valves, and fittings.
178.338-9 Holding time.
178.338-10 Accident damage protection.
178.338-11 Discharge control devices.
178.338-12 Shear section.
178.338-13 Supporting and anchoring.
178.338-14 Gauging devices.
178.338-15 Cleanliness.
178.338-16 Inspection and testing.
178.338-17 Pumps and compressors.
178.338-18 Marking.
178.338-19 Certification.
178.340-178.343 [Reserved]
178.345 General design and construction requirements applicable to 
          Specification DOT 406 (Sec. 178.346), DOT 407 (Sec. 
          178.347), and DOT 412 (Sec. 178.348) cargo tank motor 
          vehicles.
178.345-1 General requirements.
178.345-2 Material and material thickness.
178.345-3 Structural integrity.
178.345-4 Joints.
178.345-5 Manhole assemblies.
178.345-6 Supports and anchoring.
178.345-7 Circumferential reinforcements.
178.345-8 Accident damage protection.
178.345-9 Pumps, piping, hoses and connections.
178.345-10 Pressure relief.
178.345-11 Tank outlets.
178.345-12 Gauging devices.
178.345-13 Pressure and leakage tests.
178.345-14 Marking.
178.345-15 Certification.
178.346 Specification DOT 406; cargo tank motor vehicle.
178.346-1 General requirements.
178.346-2 Material and thickness of material.
178.346-3 Pressure relief.
178.346-4 Outlets.
178.346-5 Pressure and leakage tests.
178.347 Specification DOT 407; cargo tank motor vehicle.
178.347-1 General requirements.
178.347-2 Material and thickness of material.
178.347-3 Manhole assemblies.
178.347-4 Pressure relief.
178.347-5 Pressure and leakage test.
178.348 Specification DOT 412; cargo tank motor vehicle.
178.348-1 General requirements.
178.348-2 Material and thickness of material.
178.348-3 Pumps, piping, hoses and connections.
178.348-4 Pressure relief.
178.348-5 Pressure and leakage test.

   Subpart K_Specifications for Packagings for Class 7 (Radioactive) 
                                Materials

178.350 Specification 7A; general packaging, Type A.
178.356 Specification 20PF phenolic-foam insulated, metal overpack.
178.356-1 General requirements.
178.356-2 Materials of construction and other requirements.
178.356-3 Tests.
178.356-4 Required markings.
178.356-5 Typical assembly detail.

[[Page 9]]

178.358 Specification 21PF fire and shock resistant, phenolic-foam 
          insulated, metal overpack.
178.358-1 General requirements.
178.358-2 Materials of construction and other requirements.
178.358-3 Modification of Specification 21PF-1 overpacks.
178.358-4 Construction of Specification 21PF-1B overpacks.
178.358-5 Required markings.
178.358-6 Typical assembly detail.
178.360 Specification 2R; inside containment vessel.
178.360-1 General requirements.
178.360-2 Manufacture.
178.360-3 Dimensions.
178.360-4 Closure devices.

       Subpart L_Non-bulk Performance-Oriented Packaging Standards

178.500 Purpose, scope and definitions.
178.502 Identification codes for packagings.
178.503 Marking of packagings.
178.504 Standards for steel drums.
178.505 Standards for aluminum drums.
178.506 Standards for metal drums other than steel or aluminum.
178.507 Standards for plywood drums.
178.508 Standards for fiber drums.
178.509 Standards for plastic drums and jerricans.
178.510 Standards for wooden barrels.
178.511 Standards for aluminum and steel jerricans.
178.512 Standards for steel or aluminum boxes.
178.513 Standards for boxes of natural wood.
178.514 Standards for plywood boxes.
178.515 Standards for reconstituted wood boxes.
178.516 Standards for fiberboard boxes.
178.517 Standards for plastic boxes.
178.518 Standards for woven plastic bags.
178.519 Standards for plastic film bags.
178.520 Standards for textile bags.
178.521 Standards for paper bags.
178.522 Standards for composite packagings with inner plastic 
          receptacles.
178.523 Standards for composite packagings with inner glass, porcelain, 
          or stoneware receptacles.

          Subpart M_Testing of Non-bulk Packagings and Packages

178.600 Purpose and scope.
178.601 General requirements.
178.602 Preparation of packagings and packages for testing.
178.603 Drop test.
178.604 Leakproofness test.
178.605 Hydrostatic pressure test.
178.606 Stacking test.
178.607 Cooperage test for bung-type wooden barrels.
178.608 Vibration standard.
178.609 Test requirements for packagings for infectious substances.

              Subpart N_IBC Performance-Oriented Standards

178.700 Purpose, scope and definitions.
178.702 IBC codes.
178.703 Marking of IBCs.
178.704 General IBC standards.
178.705 Standards for metal IBCs.
178.706 Standards for rigid plastic IBCs.
178.707 Standards for composite IBCs.
178.708 Standards for fiberboard IBCs.
178.709 Standards for wooden IBCs.
178.710 Standards for flexible intermediate bulk containers.

                        Subpart O_Testing of IBCs

178.800 Purpose and scope.
178.801 General requirements.
178.802 Preparation of fiberboard IBCs for testing.
178.803 Testing and certification of IBCs.
178.810 Drop test.
178.811 Bottom lift test.
178.812 Top lift test.
178.813 Leakproofness test.
178.814 Hydrostatic pressure test.
178.815 Stacking test.
178.816 Topple test.
178.817 Righting test.
178.818 Tear test.
178.819 Vibration test.

                  Subpart P_Large Packagings Standards

178.900 Purpose and scope.
178.905 Large Packaging identification codes.
178.910 Marking of Large Packagings.
178.915 General Large Packaging standards.
178.920 Standards for metal Large Packagings.
178.925 Standards for rigid plastic Large Packagings.
178.930 Standards for fiberboard Large Packagings.
178.935 Standards for wooden Large Packagings.
178.940 Standards for flexible Large Packagings.

                  Subpart Q_Testing of Large Packagings

178.950 Purpose and scope.
178.955 General requirements.
178.960 Preparation of Large Packagings for testing.
178.965 Drop test.
178.970 Bottom lift test.
178.975 Top lift test.
178.980 Stacking test.
178.985 Vibration test.

Appendix A to Part 178--Specifications for Steel

[[Page 10]]

Appendix B to Part 178--Alternative Leakproofness Test Methods
Appendix C to Part 178--Nominal and Minimum Thicknesses of Steel Drums 
          and Jerricans
Appendix D to Part 178--Thermal Resistance Test
Appendix E to Part 178--Flame Penetration Resistance Test

    Authority: 49 U.S.C. 5101-5128; 49 CFR 1.53.



Sec. 178.1  Purpose and scope.

    This part prescribes the manufacturing and testing specifications 
for packaging and containers used for the transportation of hazardous 
materials in commerce.

[Amdt. 178-40, 42 FR 2689, Jan. 13, 1977. Redesignated by Amdt. 178-97, 
55 FR 52715, Dec. 21, 1990]



Sec. 178.2  Applicability and responsibility.

    (a) Applicability. (1) The requirements of this part apply to 
packagings manufactured--
    (i) To a DOT specification, regardless of country of manufacture; or
    (ii) To a UN standard, for packagings manufactured within the United 
States. For UN standard packagings manufactured outside the United 
States, see Sec. 173.24(d)(2) of this subchapter. For UN standard 
packagings for which standards are not prescribed in this part, see 
Sec. 178.3(b).
    (2) A manufacturer of a packaging subject to the requirements of 
this part is primarily responsible for compliance with the requirements 
of this part. However, any person who performs a function prescribed in 
this part shall perform that function in accordance with this part.
    (b) Specification markings. When this part requires that a packaging 
be marked with a DOT specification or UN standard marking, marking of 
the packaging with the appropriate DOT or UN markings is the 
certification that--
    (1) Except as otherwise provided in this section, all requirements 
of the DOT specification or UN standard, including performance tests, 
are met; and
    (2) All functions performed by, or on behalf of, the person whose 
name or symbol appears as part of the marking conform to requirements 
specified in this part.
    (c) Notification. (1) Except as specifically provided in Sec. Sec. 
178.337-18 and 178.345-10 of this part, the manufacturer or other person 
certifying compliance with the requirements of this part, and each 
subsequent distributor of that packaging must:
    (i) Notify each person to whom that packaging is transferred--
    (A) Of all requirements in this part not met at the time of 
transfer, and
    (B) With information specifying the type(s) and dimensions of the 
closures, including gaskets and any other components needed to ensure 
that the packaging is capable of successfully passing the applicable 
performance tests. This information must include any procedures to be 
followed, including closure instructions for inner packagings and 
receptacles, to effectively assemble and close the packaging for the 
purpose of preventing leakage in transportation. Closure instructions 
must provide for a consistent and repeatable means of closure that is 
sufficient to ensure the packaging is closed in the same manner as it 
was tested. For packagings sold or represented as being in conformance 
with the requirements of this subchapter applicable to transportation by 
aircraft, this information must include relevant guidance to ensure that 
the packaging, as prepared for transportation, will withstand the 
pressure differential requirements in Sec. 173.27 of this subchapter.
    (ii) Retain copies of each written notification for the amount of 
time that aligns with the packaging's periodic retest date, i.e., every 
12 months for single or composite packagings and every 24 months for 
combination packagings; and
    (iii) Make copies of all written notifications available for 
inspection by a representative of the Department.
    (2) The notification required in accordance with this paragraph (c) 
may be in writing or by electronic means, including e-mailed 
transmission or transmission on a CD or similar device. If a 
manufacturer or subsequent distributor of the packaging utilizes 
electronic means to make the required notifications, the notification 
must be specific to the packaging in question and must be in a form that 
can be

[[Page 11]]

printed in hard copy by the person receiving the notification.
    (d) Except as provided in paragraph (c) of this section, a packaging 
not conforming to the applicable specifications or standards in this 
part may not be marked to indicate such conformance.
    (e) Definitions. For the purpose of this part--
    Manufacturer means the person whose name and address or symbol 
appears as part of the specification markings required by this part or, 
for a packaging marked with the symbol of an approval agency, the person 
on whose behalf the approval agency certifies the packaging.
    Specification markings mean the packaging identification markings 
required by this part including, where applicable, the name and address 
or symbol of the packaging manufacturer or approval agency.
    (f) No packaging may be manufactured or marked to a packaging 
specification that was in effect on September 30, 1991, and that was 
removed from this part 178 by a rule published in the Federal Register 
on December 21, 1990 and effective October 1, 1991.

[Amdt. 178-97, 55 FR 52715, Dec. 21, 1990; 56 FR 66284, Dec. 20, 1991, 
as amended by Amdt. No. 178-106, 59 FR 67519, Dec. 29, 1994; Amdt. 178-
117, 62 FR 14338, Mar. 26, 1997; 68 FR 45041, July 31, 2003; 69 FR 
34612, June 22, 2004; 75 FR 5395, Feb. 2, 2010; 75 FR 60339, Sept. 30, 
2010]



Sec. 178.3  Marking of packagings.

    (a) Each packaging represented as manufactured to a DOT 
specification or a UN standard must be marked on a non-removable 
component of the packaging with specification markings conforming to the 
applicable specification, and with the following:
    (1) In an unobstructed area, with letters, and numerals identifying 
the standards or specification (e.g. UN 1A1, DOT 4B240ET, etc.).
    (2) Unless otherwise specified in this part, with the name and 
address or symbol of the packaging manufacturer or, where specifically 
authorized, the symbol of the approval agency certifying compliance with 
a UN standard. Symbols, if used, must be registered with the Associate 
Administrator. Duplicative symbols are not authorized.
    (3) The markings must be stamped, embossed, burned, printed or 
otherwise marked on the packaging to provide adequate accessibility, 
permanency, contrast, and legibility so as to be readily apparent and 
understood.
    (4) Unless otherwise specified, letters and numerals must be at 
least 12.0 mm (0.47 inches) in height except that for packagings of less 
than or equal to 30 L (7.9 gallons) capacity for liquids or 30 kg (66 
pounds) capacity for solids the height must be at least 6.0 mm (0.2 
inches). For packagings having a capacity of 5 L (1 gallon) or 5 kg (11 
pounds) or less, letters and numerals must be of an appropriate size.
    (5) For packages with a gross mass of more than 30 kg (66 pounds), 
the markings or a duplicate thereof must appear on the top or on a side 
of the packaging.
    (b) A UN standard packaging for which the UN standard is set forth 
in this part may be marked with the United Nations symbol and other 
specification markings only if it fully conforms to the requirements of 
this part. A UN standard packaging for which the UN standard is not set 
forth in this part may be marked with the United Nations symbol and 
other specification markings for that standard as provided in the ICAO 
Technical Instructions or the IMDG Code subject to the following 
conditions:
    (1) The U.S. manufacturer must establish that the packaging conforms 
to the applicable provisions of the ICAO Technical Instructions (IBR, 
see Sec. 171.7 of this subchapter) or the IMDG Code (IBR, see Sec. 
171.7 of this subchapter), respectively.
    (2) If an indication of the name of the manufacturer or other 
identification of the packaging as specified by the competent authority 
is required, the name and address or symbol of the manufacturer or the 
approval agency certifying compliance with the UN standard must be 
entered. Symbols, if used, must be registered with the Associate 
Administrator.
    (3) The letters ``USA'' must be used to indicate the State 
authorizing the allocation of the specification marks if the packaging 
is manufactured in the United States.

[[Page 12]]

    (c) Where a packaging conforms to more than one UN standard or DOT 
specification, the packaging may bear more than one marking, provided 
the packaging meets all the requirements of each standard or 
specification. Where more than one marking appears on a packaging, each 
marking must appear in its entirety.
    (d) No person may mark or otherwise certify a packaging or container 
as meeting the requirements of a manufacturing special permit unless 
that person is the holder of or a party to that special permit, an agent 
of the holder or party for the purpose of marking or certification, or a 
third party tester.

[Amdt. 178-97, 55 FR 52716, Dec. 21, 1990; 56 FR 66284, Dec. 20, 1991, 
as amended by Amdt. No. 178-106, 59 FR 67519, Dec. 29, 1994; Amdt. 178-
113, 61 FR 21102, May 9, 1996; 65 FR 50462, Aug. 18, 2000; 66 FR 45386, 
Aug. 28, 2001; 67 FR 61015, Sept. 27, 2002; 68 FR 75748, Dec. 31, 2003; 
70 FR 73166, Dec. 9, 2005]

Subpart A [Reserved]



       Subpart B_Specifications for Inside Containers, and Linings

    Source: 29 FR 18823, Dec. 29, 1964, unless otherwise noted. 
Redesignated at 32 FR 5606, Apr. 5, 1967.



Sec. 178.33  Specification 2P; inner nonrefillable metal receptacles.



Sec. 178.33-1  Compliance.

    (a) Required in all details.
    (b) [Reserved]



Sec. 178.33-2  Type and size.

    (a) Single-trip inside containers. Must be seamless, or with seams, 
welded, soldered, brazed, double seamed, or swedged.
    (b) The maximum capacity of containers in this class shall not 
exceed one liter (61.0 cubic inches). The maximum inside diameter shall 
not exceed 3 inches.

[29 FR 18813, Dec. 29, 1964, as amended by Order 71, 31 FR 9074, July 1, 
1966. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 
178-101, 58 FR 50237, Sept. 24, 1993; 66 FR 45386, Aug. 28, 2001]



Sec. 178.33-3  Inspection.

    (a) By competent inspector.
    (b) [Reserved]



Sec. 178.33-4  Duties of inspector.

    (a) To inspect material and completed containers and witness tests, 
and to reject defective materials or containers.
    (b) [Reserved]



Sec. 178.33-5  Material.

    (a) Uniform quality steel plate such as black plate, electro-tin 
plate, hot dipped tin plate, tern plate or other commercially accepted 
can making plate; or nonferrous metal of uniform drawing quality.
    (b) Material with seams, cracks, laminations or other injurious 
defects not authorized.



Sec. 178.33-6  Manufacture.

    (a) By appliances and methods that will assure uniformity of 
completed containers; dirt and scale to be removed as necessary; no 
defect acceptable that is likely to weaken the finished container 
appreciably; reasonably smooth and uniform surface finish required.
    (b) Seams when used must be as follows:
    (1) Circumferential seams: By welding, swedging, brazing, soldering, 
or double seaming.
    (2) Side seams: By welding, brazing, or soldering.
    (c) Ends: The ends shall be of pressure design.

[29 FR 18823, Dec. 29, 1964, as amended by Order 71, 31 FR 9074, July 1, 
1966. Redesignated at 32 FR 5606, Apr. 5, 1967]



Sec. 178.33-7  Wall thickness.

    (a) The minimum wall thickness for any container shall be 0.007 
inch.
    (b) [Reserved]

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967]



Sec. 178.33-8  Tests.

    (a) One out of each lot of 25,000 containers or less, successively 
produced per day shall be pressure tested to destruction and must not 
burst below 240 psig gauge pressure. The container

[[Page 13]]

tested shall be complete with end assembled.
    (b) Each such 25,000 containers or less, successively produced per 
day, shall constitute a lot and if the test container shall fail, the 
lot shall be rejected or ten additional containers may be selected at 
random and subjected to the test under which failure occurred. These 
containers shall be complete with ends assembled. Should any of the ten 
containers thus tested fail, the entire lot must be rejected. All 
containers constituting a lot shall be of like material, size, design 
construction, finish, and quality.

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967, as amended by 66 FR 45387, Aug. 28, 2001]



Sec. 178.33-9  Marking.

    (a) By means of printing, lithographing, embossing, or stamping, 
each container must be marked to show:
    (1) DOT-2P.
    (2) Name or symbol of person making the mark specified in paragraph 
(a)(1) of this section. Symbol, if used, must be registered with the 
Associate Administrator.
    (b) [Reserved]

[Amdt. 178-40, 41 FR 38181, Sept. 9, 1976, as amended by Amdt. 178-97, 
56 FR 66287, Dec. 20, 1991; 66 FR 45386, Aug. 28, 2001]



Sec. 178.33a  Specification 2Q; inner nonrefillable metal receptacles.



Sec. 178.33a-1  Compliance.

    (a) Required in all details.
    (b) [Reserved]

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967]



Sec. 178.33a-2  Type and size.

    (a) Single-trip inside containers. Must be seamless, or with seams 
welded, soldered, brazed, double seamed, or swedged.
    (b) The maximum capacity of containers in this class shall not 
exceed 1 L (61.0 cubic inches). The maximum inside diameter shall not 
exceed 3 inches.

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967, and amended by Amdt. 178-43, 42 FR 42208, Aug. 22, 1977; Amdt. 
178-101, 58 FR 50237, Sept. 24, 1993; 66 FR 45387, Aug. 28, 2001]



Sec. 178.33a-3  Inspection.

    (a) By competent inspector.
    (b) [Reserved]

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967]



Sec. 178.33a-4  Duties of inspector.

    (a) To inspect material and completed containers and witness tests, 
and to reject defective materials or containers.
    (b) [Reserved]

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967]



Sec. 178.33a-5  Material.

    (a) Uniform quality steel plate such as black plate, electrotin 
plate, hot dipped tinplate, ternplate or other commercially accepted can 
making plate; or nonferrous metal of uniform drawing quality.
    (b) Material with seams, cracks, laminations or other injurious 
defects not authorized.

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967]



Sec. 178.33a-6  Manufacture.

    (a) By appliances and methods that will assure uniformity of 
completed containers; dirt and scale to be removed as necessary; no 
defect acceptable that is likely to weaken the finished container 
appreciably; reasonably smooth and uniform surface finish required.
    (b) Seams when used must be as follows:
    (1) Circumferential seams. By welding, swedging, brazing, soldering, 
or double seaming.
    (2) Side seams. By welding, brazing or soldering.
    (c) Ends. The ends shall be of pressure design.

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967]



Sec. 178.33a-7  Wall thickness.

    (a) The minimum wall thickness for any container shall be 0.008 
inch.
    (b) [Reserved]

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967]

[[Page 14]]



Sec. 178.33a-8  Tests.

    (a) One out of each lot of 25,000 containers or less, successively 
produced per day, shall be pressure tested to destruction and must not 
burst below 270 psig gauge pressure. The container tested shall be 
complete with end assembled.
    (b) Each such 25,000 containers or less, successively produced per 
day, shall constitute a lot and if the test container shall fail, the 
lot shall be rejected or ten additional containers may be selected at 
random and subjected to the test under which failure occurred. These 
containers shall be complete with ends assembled. Should any of the ten 
containers thus tested fail, the entire lot must be rejected. All 
containers constituting a lot shall be of like material, size, design, 
construction, finish and quality.

[Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 
1967, as amended by 66 FR 45387, Aug. 28, 2001]



Sec. 178.33a-9  Marking.

    (a) By means of printing, lithographing, embossing, or stamping, 
each container must be marked to show:
    (1) DOT-2Q.
    (2) Name or symbol of person making the mark specified in paragraph 
(a)(1) of this section. Symbol, if used, must be registered with the 
Associate Administrator.
    (b) [Reserved]

[Amdt. 178-40, 41 FR 38181, Sept. 9, 1976, as amended by Amdt. 178-97, 
56 FR 66287, Dec. 20, 1991; 66 FR 45386, Aug. 28, 2001]



Sec. 178.33b  Specification 2S; inner nonrefillable plastic receptacles.



Sec. 178.33b-1  Compliance.

    (a) Required in all details.
    (b) [Reserved]

[74 FR 2268, Jan. 14, 2009]



Sec. 178.33b-2  Type and size.

    (a) Single-trip inside containers.
    (b) The maximum capacity of containers in this class shall not 
exceed one liter (61.0 cubic inches). The maximum inside diameter shall 
not exceed 3 inches.

[74 FR 2268, Jan. 14, 2009]



Sec. 178.33b-3  Inspection.

    (a) By competent inspector.
    (b) [Reserved]

[74 FR 2268, Jan. 14, 2009]



Sec. 178.33b-4  Duties of inspector.

    (a) To inspect material and completed containers and witness tests, 
and to reject defective materials or containers.
    (b) [Reserved]

[74 FR 2268, Jan. 14, 2009]



Sec. 178.33b-5  Material.

    (a) The receptacles must be constructed of polyethylene 
terephthalate (PET), polyethylene napthalate (PEN), polyamide (Nylon) or 
a blend of PET, PEN, ethyl vinyl alcohol (EVOH) and/or Nylon.
    (b) Material with seams, cracks, laminations or other injurious 
defects are forbidden.

[74 FR 2268, Jan. 14, 2009]



Sec. 178.33b-6  Manufacture.

    (a) Each container must be manufactured by thermoplastic processes 
that will assure uniformity of the completed container. No used material 
other than production residues or regrind from the same manufacturing 
process may be used. The packaging must be adequately resistant to aging 
and to degradation caused either by the substance contained or by 
ultraviolet radiation.
    (b) [Reserved]

[74 FR 2268, Jan. 14, 2009]



Sec. 178.33b-7  Design qualification test.

    (a) Drop testing. (1) To ensure that creep does not affect the 
ability of the container to retain the contents, each new design must be 
drop tested as follows: Three groups of twenty-five filled containers 
must be dropped from 1.8 m (5.9 ft) on to a rigid, non-resilient, flat 
and horizontal surface. One group must be conditioned at 38 [deg]C (100 
[deg]F) for 26 weeks, the second group for 100 hours at 50 [deg]C (122 
[deg]F) and the third group for 18 hours at 55 [deg]C (131 [deg]F), 
prior to performing the drop test. The closure, or sealing component of 
the container, must not be protected during the test. The orientation of 
the test container

[[Page 15]]

at drop must be statistically random, but direct impact on the valve or 
valve closure must be avoided.
    (2) Criteria for passing the drop test: The containers must not 
break or leak.
    (b) Design qualification testing must be completed if the design is 
manufactured with a new mold or if there is any change in the properties 
of the material of construction.

[75 FR 73, Jan. 4, 2010]



Sec. 178.33b-8  Production tests.

    (a) Burst Testing. (1) One out of each lot of 5,000 containers or 
less, successively produced per day must be pressure tested to 
destruction and must not burst below 240 psig. The container tested must 
be complete as intended for transportation.
    (2) Each such 5,000 containers or less, successively produced per 
day, shall constitute a lot and if the test container shall fail, the 
lot shall be rejected or ten additional containers may be selected at 
random and subjected to the test under which failure occurred. These 
containers shall be complete as intended for transportation. Should any 
of the ten containers thus tested fail, the entire lot must be rejected. 
All containers constituting a lot shall be of like material, size, 
design construction, finish, and quality.
    (b) [Reserved]

[74 FR 2268, Jan. 14, 2009, as amended at 75 FR 74, Jan. 4, 2010]



Sec. 178.33b-9  Marking.

    (a) Each container must be clearly and permanently marked to show:
    (1) DOT-2S.
    (2) Name or symbol of person making the mark specified in paragraph 
(a)(1) of this section. Symbol, if used, must be registered with the 
Associate Administrator.
    (b) [Reserved]

[74 FR 2268, Jan. 14, 2009]



                 Subpart C_Specifications for Cylinders



Sec. 178.35  General requirements for specification cylinders.

    (a) Compliance. Compliance with the requirements of this subpart is 
required in all details.
    (b) Inspections and analyses. Chemical analyses and tests required 
by this subchapter must be made within the United States, unless 
otherwise approved in writing by the Associate Administrator, in 
accordance with subpart I of part 107 of this chapter. Inspections and 
verification must be performed by--
    (1) An independent inspection agency approved in writing by the 
Associate Administrator, in accordance with subpart I of part 107 of 
this chapter; or
    (2) For DOT Specifications 3B, 3BN, 3E, 4B, 4BA, 4D (water capacity 
less than 1,100 cubic inches), 4B240ET, 4AA480, 4L, 8, 8AL, 4BW, 39 
(marked service pressure 900 p.s.i.g. or lower) and 4E manufactured in 
the United States, a competent inspector of the manufacturer.
    (c) Duties of inspector. The inspector shall determine that each 
cylinder made is in conformance with the applicable specification. 
Except as otherwise specified in the applicable specification, the 
inspector shall perform the following:
    (1) Inspect all material and reject any not meeting applicable 
requirements. For cylinders made by the billet-piercing process, billets 
must be inspected and shown to be free from pipe, cracks, excessive 
segregation and other injurious defects after parting or, when 
applicable, after nick and cold break.
    (2) Verify the material of construction meets the requirements of 
the applicable specification by--
    (i) Making a chemical analysis of each heat of material;
    (ii) Obtaining a certified chemical analysis from the material 
manufacturer for each heat of material (a ladle analysis is acceptable); 
or
    (iii) If an analysis is not provided for each heat of material by 
the material manufacturer, by making a check analysis of a sample from 
each coil, sheet, or tube.
    (3) Verify compliance of cylinders with the applicable specification 
by--
    (i) Verifying identification of material is proper;
    (ii) Inspecting the inside of the cylinder before closing in ends;
    (iii) Verifying that the heat treatment is proper;

[[Page 16]]

    (iv) Obtaining samples for all tests and check chemical analyses 
(Note: Recommended locations for test specimens taken from welded 
cylinders are depicted in Figures 1 through 5 in Appendix C to this 
subpart for the specific construction design.);
    (v) Witnessing all tests;
    (vi) Verify threads by gauge;
    (vii) Reporting volumetric capacity and tare weight (see report 
form) and minimum thickness of wall noted; and
    (viii) Verifying that each cylinder is marked in accordance with the 
applicable specification.
    (4) Inspector's report. Prepare a report containing, at a minimum, 
the applicable information listed in CGA C-11 (IBR, see Sec. 171.7 of 
this subchapter). Any additional information or markings that are 
required by the applicable specification must be shown on the test 
report. The signature of the inspector on the reports certifies that the 
processes of manufacture and heat treatment of cylinders were observed 
and found satisfactory. The inspector must furnish the completed test 
reports required by this subpart to the maker of the cylinder and, upon 
request, to the purchaser. The test report must be retained by the 
inspector for fifteen years from the original test date of the cylinder.
    (d) Defects and attachments. Cylinders must conform to the 
following:
    (1) A cylinder may not be constructed of material with seams, cracks 
or laminations, or other injurious defects.
    (2) Metal attachments to cylinders must have rounded or chamfered 
corners or must be protected in such a manner as to prevent the 
likelihood of causing puncture or damage to other hazardous materials 
packages. This requirement applies to anything temporarily or 
permanently attached to the cylinder, such as metal skids.
    (e) Safety devices. Pressure relief devices and protection for 
valves, safety devices, and other connections, if applied, must be as 
required or authorized by the appropriate specification, and as required 
in Sec. 173.301 of this subchapter.
    (f) Markings. Markings on a DOT Specification cylinder must conform 
to applicable requirements.
    (1) Each cylinder must be marked with the following information:
    (i) The DOT specification marking must appear first, followed 
immediately by the service pressure. For example, DOT-3A1800.
    (ii) The serial number must be placed just below or immediately 
following the DOT specification marking.
    (iii) A symbol (letters) must be placed just below, immediately 
before or following the serial number. Other variations in sequence of 
markings are authorized only when necessitated by a lack of space. The 
symbol and numbers must be those of the manufacturer. The symbol must be 
registered with the Associate Administrator; duplications are not 
authorized.
    (iv) The inspector's official mark and date of test (such as 5-95 
for May 1995) must be placed near the serial number. This information 
must be placed so that dates of subsequent tests can be easily added. An 
example of the markings prescribed in this paragraph (f)(1) is as 
follows:

DOT-3A1800
1234
XY
AB 5-95

    Or;

DOT-3A1800-1234-XY
AB 5-95

Where:

DOT-3A = specification number
1800 = service pressure
1234 = serial number
XY = symbol of manufacturer
AB = inspector's mark
5-95 = date of test

    (2) Additional required marking must be applied to the cylinder as 
follows:
    (i) The word ``spun'' or ``plug'' must be placed near the DOT 
specification marking when an end closure in the finished cylinder has 
been welded by the spinning process, or effected by plugging.
    (ii) As prescribed in specification 3HT (Sec. 178.44) or 3T (Sec. 
178.45), if applicable.
    (3) Marking exceptions. A DOT 3E cylinder is not required to be 
marked with an inspector's mark or a serial number.
    (4) Unless otherwise specified in the applicable specification, the 
markings on each cylinder must be stamped plainly and permanently on the 
shoulder, top head, or neck.

[[Page 17]]

    (5) The size of each marking must be at least 0.25 inch or as space 
permits.
    (6) Other markings are authorized provided they are made in low 
stress areas other than the side wall and are not of a size and depth 
that will create harmful stress concentrations. Such marks may not 
conflict with any DOT required markings.
    (g) Manufacturer's reports. At or before the time of delivery to the 
purchaser, the cylinder manufacturer must have all completed 
certification documents listed in CGA C-11. The manufacturer of the 
cylinders must retain the reports required by this subpart for 15 years 
from the original test date of the cylinder.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45185, 
Aug. 28, 2001; 67 FR 51652, Aug. 8, 2002; 68 FR 75748, Dec. 31, 2003; 76 
FR 43531, July 20, 2011]



Sec. 178.36  Specification 3A and 3AX seamless steel cylinders.

    (a) Type size and service pressure. In addition to the requirements 
of Sec. 178.35, cylinders must conform to the following:
    (1) A DOT-3A cylinder is a seamless steel cylinder with a water 
capacity (nominal) not over 1,000 pounds and a service pressure of at 
least 150 psig.
    (2) A DOT-3AX is a seamless steel cylinder with a water capacity not 
less than 1,000 pounds and a service pressure of at least 500 psig, 
conforming to the following requirements:
    (i) Assuming the cylinder is to be supported horizontally at its two 
ends only and to be uniformly loaded over its entire length consisting 
of the weight per unit of length of the straight cylindrical portion 
filled with water and compressed to the specified test pressure; the sum 
of two times the maximum tensile stress in the bottom fibers due to 
bending, plus that in the same fibers (longitudinal stress), due to 
hydrostatic test may not exceed 80 percent of the minimum yield strength 
of the steel at such maximum stress. Wall thickness must be increased 
when necessary to meet the requirement.
    (ii) To calculate the maximum longitudinal tensile stress due to 
bending, the following formula must be used:

S=Mc/I

    (iii) To calculate the maximum longitudinal tensile stress due to 
hydrostatic test pressure, the following formula must be used:

S = A1 P/A2

where:

S = tensile stress--p.s.i.;
M = bending moment-inch pounds--(wl\2\)/8;
w = weight per inch of cylinder filled with water;
l = length of cylinder-inches;
c = radius (D)/(2) of cylinder-inches;
I = moment of inertia--0.04909 (D\4\-d\4\) inches fourth;
D = outside diameter-inches;
d = inside diameter-inches;
A1 = internal area in cross section of cylinder-square 
          inches;
A2 = area of metal in cross section of cylinder-square 
          inches;
P=hydrostatic test pressure-psig.

    (b) Steel. Open-hearth or electric steel of uniform quality must be 
used. Content percent may not exceed the following: Carbon, 0.55; 
phosphorous, 0.045; sulphur, 0.050.
    (c) Identification of material. Material must be identified by any 
suitable method, except that plates and billets for hot-drawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No fissure or other defect is permitted 
that is likely to weaken the finished cylinder appreciably. A reasonably 
smooth and uniform surface finish is required. If not originally free 
from such defects, the surface may be machined or otherwise treated to 
eliminate these defects. The thickness of the bottoms of cylinders 
welded or formed by spinning is, under no condition, to be less than two 
times the minimum wall thickness of the cylindrical shell; such bottom 
thicknesses must be measured within an area bounded by a line 
representing the points of contact between the cylinder and floor when 
the cylinder is in a vertical position.
    (e) Welding or brazing. Welding or brazing for any purpose 
whatsoever is prohibited except as follows:
    (1) Welding or brazing is authorized for the attachment of neckrings 
and footrings which are non-pressure parts

[[Page 18]]

and only to the tops and bottoms of cylinders having a service pressure 
of 500 psig or less. Cylinders, neckrings, and footrings must be made of 
weldable steel, the carbon content of which may not exceed 0.25 percent 
except in the case of 4130X steel which may be used with proper welding 
procedures.
    (2) As permitted in paragraph (d) of this section.
    (3) Cylinders used solely in anhydrous ammonia service may have a 
\1/2\ inch diameter bar welded within their concave bottoms.
    (f) Wall thickness. For cylinders with service pressure less than 
900 psig, the wall stress may not exceed 24,000 psig. A minimum wall 
thickness of 0.100 inch is required for any cylinder over 5 inches 
outside diameter. Wall stress calculation must be made by using the 
following formula:

S = [P(1.3D\2\+0.4d\2\)]/(D\2\-d\2\)

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test or 450 psig 
          whichever is the greater;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. The completed cylinder must be uniformly and 
properly heat-treated prior to tests.
    (h) Openings in cylinders and connections (valves, fuse plugs, etc.) 
for those openings. Threads are required on openings.
    (1) Threads must be clean cut, even, without checks, and to gauge.
    (2) Taper threads, when used, must be of length not less than as 
specified for American Standard taper pipe threads.
    (3) Straight threads having at least 6 engaged threads are 
authorized. Straight threads must have a tight fit and calculated shear 
strength of at least 10 times the test pressure of the cylinder. 
Gaskets, adequate to prevent leakage, are required.
    (i) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test, as follows:
    (1) The test must be by water-jacket, or other suitable methods, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus the test pressure cannot be maintained the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent, volumetric expansion may not exceed 10 percent of the 
total volumetric expansion at test pressure.
    (4) Each cylinder must be tested to at least \5/3\ times service 
pressure.
    (j) Flattening test. A flattening test must be performed on one 
cylinder taken at random out of each lot of 200 or less, by placing the 
cylinder between wedge shaped knife edges having a 60[deg] included 
angle, rounded to \1/2\-inch radius. The longitudinal axis of the 
cylinder must be at a 90-degree angle to knife edges during the test. 
For lots of 30 or less, flattening tests are authorized to be made on a 
ring at least 8 inches long cut from each cylinder and subjected to same 
heat treatment as the finished cylinder.
    (k) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material as follows:
    (1) The test is required on 2 specimens cut from 1 cylinder taken at 
random out of each lot of 200 or less. For lots of 30 or less, physical 
tests are authorized to be made on a ring at least 8 inches long cut 
from each cylinder and subjected to same heat treatment as the finished 
cylinder.
    (2) Specimens must conform to the following:
    (i) Gauge length of 8 inches with a width of not over 1\1/2\ inches, 
a gauge length of 2 inches with a width of not over 1\1/2\ inches, or a 
gauge length of at least 24 times thickness with width not over 6 times 
thickness is authorized when cylinder wall is not over \3/16\ inch 
thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends

[[Page 19]]

may be flattened to within 1 inch of each end of the reduced section.
    (iii) When size of cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold, by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2-percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy the entire stress-strain diagram 
must be plotted and the yield strength determined from the 0.2 percent 
offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psig and the 
strain indicator reading must be set at the calculated corresponding 
strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (l) Acceptable results for physical and flattening tests. Either of 
the following is an acceptable result:
    (1) An elongation at least 40 percent for a 2-inch gauge length or 
at least 20 percent in other cases and yield strength not over 73 
percent of tensile strength. In this instance, the flattening test is 
not required.
    (2) An elongation at least 20 percent for a 2-inch gauge length or 
10 percent in other cases and a yield strength not over 73 percent of 
tensile strength. In this instance, the flattening test is required, 
without cracking, to 6 times the wall thickness.
    (m) Leakage test. All spun cylinders and plugged cylinders must be 
tested for leakage by gas or air pressure after the bottom has been 
cleaned and is free from all moisture subject to the following 
conditions and limitations:
    (1) Pressure, approximately the same as but no less than service 
pressure, must be applied to one side of the finished bottom over an 
area of at least \1/16\ of the total area of the bottom but not less 
than \3/4\ inch in diameter, including the closure, for at least 1 
minute, during which time the other side of the bottom exposed to 
pressure must be covered with water and closely examined for indications 
of leakage. Except as provided in paragraph (n) of this section, a 
cylinder that is leaking must be rejected.
    (2) A spun cylinder is one in which an end closure in the finished 
cylinder has been welded by the spinning process.
    (3) A plugged cylinder is one in which a permanent closure in the 
bottom of a finished cylinder has been effected by a plug.
    (4) As a safety precaution, if the manufacturer elects to make this 
test before the hydrostatic test, the manufacturer should design the 
test apparatus so that the pressure is applied to the smallest area 
practicable, around the point of closure, and so as to use the smallest 
possible volume of air or gas.
    (n) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinders. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding or spinning is not authorized. Spun 
cylinders rejected under the provisions of paragraph (m) of this section 
may be removed from the spun cylinder category

[[Page 20]]

by drilling to remove defective material, tapping and plugging.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 62 FR 51561, 
Oct. 1, 1997; 66 FR 45185, 45386-45387, Aug. 28, 2001; 67 FR 51652, Aug. 
8, 2002; 68 FR 75748, Dec. 31, 2003; 73 FR 57006, Oct. 1, 2008]



Sec. 178.37  Specification 3AA and 3AAX seamless steel cylinders.

    (a) Type, size and service pressure. In addition to the requirements 
of Sec. 178.35, cylinders must conform to the following:
    (1) A DOT-3AA cylinder is a seamless steel cylinder with a water 
capacity (nominal) of not over 1,000 pounds and a service pressure of at 
least 150 psig.
    (2) A DOT-3AAX cylinder is a seamless steel cylinder with a water 
capacity of not less than 1,000 pounds and a service pressure of at 
least 500 psig, conforming to the following requirements:
    (i) Assuming the cylinder is to be supported horizontally at its two 
ends only and to be uniformly loaded over its entire length consisting 
of the weight per unit of length of the straight cylindrical portion 
filled with water and compressed to the specified test pressure; the sum 
of two times the maximum tensile stress in the bottom fibers due to 
bending, plus that in the same fibers (longitudinal stress), due to 
hydrostatic test pressure may not exceed 80 percent of the minimum yield 
strength of the steel at such maximum stress. Wall thickness must be 
increased when necessary to meet the requirement.
    (ii) To calculate the maximum tensile stress due to bending, the 
following formula must be used:

S = Mc/I

    (iii) To calculate the maximum longitudinal tensile stress due to 
hydrostatic test pressure, the following formula must be used:

S = A\1\P/A\2\

Where:

S = tensile stress-p.s.i.;
M = bending moment-inch pounds (wl\2\)/8;
w = weight per inch of cylinder filled with water;
l = length of cylinder-inches;
c = radius (D)/(2) of cylinder-inches;
I = moment of inertia-0.04909 (D\4\-d\4\) inches fourth;
D = outside diameter-inches;
d = inside diameter-inches;
A\1\ = internal area in cross section of cylinder-square inches;
A\2\ = area of metal in cross section of cylinder-square inches;
P = hydrostatic test pressure-psig.

    (b) Authorized steel. Open-hearth, basic oxygen, or electric steel 
of uniform quality must be used. A heat of steel made under the 
specifications in table 1 of this paragraph (b), check chemical analysis 
of which is slightly out of the specified range, is acceptable, if 
satisfactory in all other respects, provided the tolerances shown in 
table 2 of this paragraph (b) are not exceeded. When a carbon-boron 
steel is used, a hardenability test must be performed on the first and 
last ingot of each heat of steel. The results of this test must be 
recorded on the Record of Chemical Analysis of Material for Cylinders 
required by Sec. 178.35. This hardness test must be made \5/16\-inch 
from the quenched end of the Jominy quench bar and the hardness must be 
at least Rc 33 and no more than Rc 53. The following chemical analyses 
are authorized:

                                                              Table 1--Authorized Materials
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                        Inter- mediate
           Designation              4130X (percent)    NE-8630 (percent)    9115 (percent)      9125 (percent)       Carbon-boron          manganese
                                     (see Note 1)        (see Note 1)        (see Note 1)        (see Note 1)          (percent)           (percent)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Carbon..........................  0.25/0.35.........  0.28/0.33.........  0.10/0.20.........  0.20/0.30.........  0.27-0.37.........  0.40 max.
Manganese.......................  0.40/0.90.........  0.70/0.90.........  0.50/0.75.........  0.50/0.75.........  0.80-1.40.........  1.35/1.65.
Phosphorus......................  0.04 max..........  0.04 max..........  0.04 max..........  0.04 max..........  0.035 max.........  0.04 max.
Sulfur..........................  0.05 max..........  0.04 max..........  0.04 max..........  0.04 max..........  0.045 max.........  0.05 max.
Silicon.........................  0.15/0.35.........  0.20/0.35.........  0.60/0.90.........  0.60/0.90.........  0.3 max...........  0.10/0.30.
Chromium........................  0.80/1.10.........  0.40/0.60.........  0.50/0.65.........  0.50/0.65.
Molybdenum......................  0.15/0.25.........  0.15/0.25
Zirconium.......................  ..................  ..................  0.05/0.15.........  0.05/0.15
Nickel..........................  ..................  0.40/0.70.........
Boron...........................  ..................  ..................  ..................  ..................  0.0005/0.003.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note 1: This designation may not be restrictive and the commercial steel is limited in analysis as shown in this table.


[[Page 21]]


                                       Table 2--Check Analysis Tolerances
----------------------------------------------------------------------------------------------------------------
                                                                                        Tolerance (percent) over
                                                                                          the maximum limit or
                                                                                         under the minimum limit
                    Element                      Limit or maximum specified (percent)  -------------------------
                                                                                           Under         Over
                                                                                          minimum      maximum
                                                                                           limit        limit
----------------------------------------------------------------------------------------------------------------
Carbon........................................  To 0.15 incl..........................         0.02         0.03
                                                Over 0.15 to 0.40 incl................          .03          .04
Manganese.....................................  To 0.60 incl..........................          .03          .03
                                                Over 0.60 to 1.15 incl................         0.04         0.04
                                                Over 1.15 to 2.50 incl................         0.05         0.05
Phosphorus\1\.................................  All ranges............................  ...........          .01
Sulphur.......................................  All ranges............................  ...........          .01
Silicon.......................................  To 0.30 incl..........................          .02          .03
                                                Over 0.30 to 1.00 incl................          .05          .05
Nickel........................................  To 1.00 incl..........................          .03          .03
Chromium......................................  To 0.90 incl..........................          .03          .03
                                                0.90 to 2.90 incl.....................          .05          .05
Molybdenum....................................  To 0.20 incl..........................          .01          .01
                                                Over 0.20 to 0.40.....................          .02          .02
Zirconium.....................................  All ranges............................          .01          .05
----------------------------------------------------------------------------------------------------------------
\1\ Rephosphorized steels not subject to check analysis for phosphorus.

    (c) Identification of material. Material must be identified by any 
suitable method except that plates and billets for hot-drawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No fissure or other defects is permitted 
that is likely to weaken the finished cylinder appreciably. A reasonably 
smooth and uniform surface finish is required. If not originally free 
from such defects, the surface may be machined or otherwise treated to 
eliminate these defects. The thickness of the bottoms of cylinders 
welded or formed by spinning is, under no condition, to be less than two 
times the minimum wall thickness of the cylindrical shell; such bottom 
thicknesses must be measured within an area bounded by a line 
representing the points of contact between the cylinder and floor when 
the cylinder is in a vertical position.
    (e) Welding or brazing. Welding or brazing for any purpose 
whatsoever is prohibited except as follows:
    (1) Welding or brazing is authorized for the attachment of neckrings 
and footrings which are non-pressure parts, and only to the tops and 
bottoms of cylinders having a service pressure of 500 psig or less. 
Cylinders, neckrings, and footrings must be made of weldable steel, the 
carbon content of which may not exceed 0.25 percent except in the case 
of 4130X steel which may be used with proper welding procedure.
    (2) As permitted in paragraph (d) of this section.
    (f) Wall thickness. The thickness of each cylinder must conform to 
the following:
    (1) For cylinders with a service pressure of less than 900 psig, the 
wall stress may not exceed 24,000 psi. A minimum wall thickness of 0.100 
inch is required for any cylinder with an outside diameter of over 5 
inches.
    (2) For cylinders with service pressure of 900 psig or more the 
minimum wall must be such that the wall stress at the minimum specified 
test pressure may not exceed 67 percent of the minimum tensile strength 
of the steel as determined from the physical tests required in 
paragraphs (k) and (l) of this section and must be not over 70,000 psi.
    (3) Calculation must be made by the formula:

S = [P(1.3D\2\+0.4d\2\)]/(D\2\-d\2\)

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test or 450 psig 
          whichever is the greater;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. The completed cylinders must be uniformly and 
properly

[[Page 22]]

heat treated prior to tests. Heat treatment of cylinders of the 
authorized analyses must be as follows:
    (1) All cylinders must be quenched by oil, or other suitable medium 
except as provided in paragraph (g)(5) of this section.
    (2) The steel temperature on quenching must be that recommended for 
the steel analysis, but may not exceed 1750 [deg]F.
    (3) All steels must be tempered at a temperature most suitable for 
that steel.
    (4) The minimum tempering temperature may not be less than 1000 
[deg]F except as noted in paragraph (g)(6) of this section.
    (5) Steel 4130X may be normalized at a temperature of 1650 [deg]F 
instead of being quenched and cylinders so normalized need not be 
tempered.
    (6) Intermediate manganese steels may be tempered at temperatures 
not less than 1150 [deg]F., and after heat treating each cylinder must 
be submitted to a magnetic test to detect the presence of quenching 
cracks. Cracked cylinders must be rejected and destroyed.
    (7) Except as otherwise provided in paragraph (g)(6) of this 
section, all cylinders, if water quenched or quenched with a liquid 
producing a cooling rate in excess of 80 percent of the cooling rate of 
water, must be inspected by the magnetic particle, dye penetrant or 
ultrasonic method to detect the presence of quenching cracks. Any 
cylinder designed to the requirements for specification 3AA and found to 
have a quenching crack must be rejected and may not be requalified. 
Cylinders designed to the requirements for specification 3AAX and found 
to have cracks must have cracks removed to sound metal by mechanical 
means. Such specification 3AAX cylinders will be acceptable if the 
repaired area is subsequently examined to assure no defect, and it is 
determined that design thickness requirements are met.
    (h) Openings in cylinders and connections (valves, fuse plugs, etc.) 
for those openings. Threads are required on openings.
    (1) Threads must be clean cut, even, without checks, and to gauge.
    (2) Taper threads, when used, must be of a length not less than as 
specified for American Standard taper pipe threads.
    (3) Straight threads having at least 6 engaged threads are 
authorized. Straight threads must have a tight fit and a calculated 
shear strength of at least 10 times the test pressure of the cylinder. 
Gaskets, adequate to prevent leakage, are required.
    (i) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Each cylinder must be tested to at least \5/3\ times the service 
pressure.
    (j) Flattening test. A flattening test must be performed on one 
cylinder taken at random out of each lot of 200 or less, by placing the 
cylinder between wedge shaped knife edges having a 60[deg] included 
angle, rounded to \1/2\-inch radius. The longitudinal axis of the 
cylinder must be at a 90-degree angle to knife edges during the test. 
For lots of 30 or less, flattening tests are authorized to be made on a 
ring at least 8 inches long cut from each cylinder and subjected to the 
same heat treatment as the finished cylinder. Cylinders may be subjected 
to a bend test in lieu of the flattening test. Two bend test specimens 
must be taken in accordance with ISO 9809-1 or ASTM E 290 (IBR, see 
Sec. 171.7 of this subchapter), and must be subjected to the bend test 
specified therein.

[[Page 23]]

    (k) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material as follows:
    (1) The test is required on 2 specimens cut from 1 cylinder taken at 
random out of each lot of 200 or less. For lots of 30 or less, physical 
tests are authorized to be made on a ring at least 8 inches long cut 
from each cylinder and subjected to the same heat treatment as the 
finished cylinder.
    (2) Specimens must conform to the following:
    (i) Gauge length of 8 inches with a width of not over 1\1/2\ inches, 
a gauge length of 2 inches with a width of not over 1\1/2\ inches, or a 
gauge length of at least 24 times the thickness with width not over 6 
times thickness when the thickness of the cylinder wall is not over \3/
16\ inch.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within 1 inch of each end of the reduced 
section.
    (iii) When size of cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold, by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi, the strain 
indicator reading being set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (l) Acceptable results for physical, flattening and bend tests. An 
acceptable result for physical and flattening tests is elongation of at 
least 20 percent for 2 inches of gauge length or at least 10 percent in 
other cases. Flattening is required, without cracking, to 6 times the 
wall thickness of the cylinder. An acceptable result for the alternative 
bend test is no crack when the cylinder is bent inward around the 
mandrel until the interior edges are not further apart than the diameter 
of the mandrel.
    (m) Leakage test. All spun cylinders and plugged cylinders must be 
tested for leakage by gas or air pressure after the bottom has been 
cleaned and is free from all moisture. Pressure, approximately the same 
as but no less than the service pressure, must be applied to one side of 
the finished bottom over an area of at least \1/16\ of the total area of 
the bottom but not less than \3/4\ inch in diameter, including the 
closure, for at least one minute, during which time the other side of 
the bottom exposed to pressure must be covered with water and closely 
examined for indications of leakage. Except as provided in paragraph (n) 
of this section, a cylinder must be rejected if there is any leaking.
    (1) A spun cylinder is one in which an end closure in the finished 
cylinder has been welded by the spinning process.
    (2) A plugged cylinder is one in which a permanent closure in the 
bottom of a finished cylinder has been effected by a plug.
    (3) As a safety precaution, if the manufacturer elects to make this 
test

[[Page 24]]

before the hydrostatic test, the manufacturer should design the test 
apparatus so that the pressure is applied to the smallest area 
practicable, around the point of closure, and so as to use the smallest 
possible volume of air or gas.
    (n) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinders. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding or spinning is not authorized. Spun 
cylinders rejected under the provision of paragraph (m) of this section 
may be removed from the spun cylinder category by drilling to remove 
defective material, tapping and plugging.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 65 FR 58631, 
Sept. 29, 2000; 66 FR 45386-45387, Aug. 28, 2001; 67 FR 51652, Aug. 8, 
2002; 68 FR 75748, Dec. 31, 2003; 76 FR 43531, July 20, 2011]



Sec. 178.38  Specification 3B seamless steel cylinders.

    (a) Type, size, and service pressure. A DOT 3B cylinder is seamless 
steel cylinder with a water capacity (nominal) of not over 1,000 pounds 
and a service pressure of at least 150 to not over 500 psig.
    (b) Steel. Open-hearth or electric steel of uniform quality must be 
used. Content percent may not exceed the following: carbon, 0.55; 
phosphorus, 0.045; sulphur, 0.050.
    (c) Identification of material. Material must be identified by any 
suitable method except that plates and billets for hot-drawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No fissure or other defect is permitted 
that is likely to weaken the finished cylinder appreciably. A reasonably 
smooth and uniform surface finish is required. If not originally free 
from such defects, the surface may be machined or otherwise treated to 
eliminate these defects. The thickness of the bottoms of cylinders 
welded or formed by spinning is, under no condition, to be less than two 
times the minimum wall thickness of the cylindrical shell; such bottom 
thicknesses to be measured within an area bounded by a line representing 
the points of contact between the cylinder and floor when the cylinder 
is in a vertical position.
    (e) Welding or brazing. Welding or brazing for any purpose 
whatsoever is prohibited except as follows:
    (1) Welding or brazing is authorized for the attachment of neckrings 
and footrings which are non-pressure parts, and only to the tops and 
bottoms of cylinders having a service pressure of 500 psig or less. 
Cylinders, neckrings, and footrings must be made of weldable steel, 
carbon content of which may not exceed 0.25 percent except in the case 
of 4130X steel which may be used with proper welding procedure.
    (2) As permitted in paragraph (d) of this section.
    (f) Wall thickness. The wall stress may not exceed 24,000 psi. The 
minimum wall thickness is 0.090 inch for any cylinder with an outside 
diameter of 6 inches. Calculation must be made by the following formula:

S = [P(1.3D\2\+0.4d\2\)]/(D\2\-d\2\)

Where:

S = wall stress in psi;
P = at least two times service pressure or 450 psig, whichever is the 
          greater;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. The completed cylinders must be uniformly and 
properly heat-treated prior to tests.
    (h) Openings in cylinders and connections (valves, fuse plugs, etc.) 
for those openings. Threads, conforming to the following, are required 
on all openings:
    (1) Threads must be clean cut, even, without checks, and to gauge.
    (2) Taper threads when used, must be of a length not less than as 
specified for American Standard taper pipe threads.
    (3) Straight threads having at least 4 engaged threads are 
authorized. Straight threads must have a tight fit, and calculated shear 
strength at least 10 times the test pressure of the cylinder. Gaskets, 
adequate to prevent leakage, are required.
    (i) Hydrostatic test. Cylinders must successfully withstand a 
hydrostatic test, as follows:

[[Page 25]]

    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy either of 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to insure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Cylinders must be tested as follows:
    (i) Each cylinder; to at least 2 times service pressure; or
    (ii) 1 cylinder out of each lot of 200 or less; to at least 3 times 
service pressure. Others must be examined under pressure of 2 times 
service pressure and show no defect.
    (j) Flattening test. A flattening test must be performed on one 
cylinder taken at random out of each lot of 200 or less, by placing the 
cylinder between wedge shaped knife edges having a 60[deg] included 
angle, rounded to \1/2\-inch radius. The longitudinal axis of the 
cylinder must be at a 90-degree angle to knife edges during the test. 
For lots of 30 or less, flattening tests are authorized to be made on a 
ring at least 8 inches long cut from each cylinder and subjected to same 
heat treatment as the finished cylinder.
    (k) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material, as follows:
    (1) The test is required on 2 specimens cut from 1 cylinder taken at 
random out of each lot of 200 or less. For lots of 30 or less, physical 
tests are authorized to be made on a ring at least 8 inches long cut 
from each cylinder and subjected to same heat treatment as the finished 
cylinder.
    (2) Specimens must conform to the following:
    (i) Gauge length of 8 inches with a width of not over 1\1/2\ inches; 
or a gauge length of 2 inches with a width of not over 1\1/2\ inches; or 
a gauge length at least 24 times the thickness with a width not over 6 
times thickness is authorized when a cylinder wall is not over \3/16\ 
inch thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within one inch of each end of the reduced 
section.
    (iii) When size of cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold, by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi, and the 
strain indicator reading being set at the calculated corresponding 
strain.

[[Page 26]]

    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (l) Acceptable results for physical and flattening tests. Either of 
the following is an acceptable result:
    (1) An elongation of at least 40 percent for a 2-inch gauge length 
or at least 20 percent in other cases and yield strength not over 73 
percent of tensile strength. In this instance, the flattening test is 
not required.
    (2) An elongation of at least 20 percent for a 2-inch gauge length 
or 10 percent in other cases and yield strength not over 73 percent of 
tensile strength. Flattening is required, without cracking, to 6 times 
the wall thickness.
    (m) Leakage test. All spun cylinders and plugged cylinders must be 
tested for leakage by gas or air pressure after the bottom has been 
cleaned and is free from all moisture, subject to the following 
conditions and limitations:
    (1) Pressure, approximately the same as but no less than service 
pressure, must be applied to one side of the finished bottom over an 
area of at least \1/16\ of the total area of the bottom but not less 
than \3/4\ inch in diameter, including the closure, for at least one 
minute, during which time the other side of the bottom exposed to 
pressure must be covered with water and closely examined for indications 
of leakage. Except as provided in paragraph (n) of this section, a 
cylinder must be rejected if there is any leaking.
    (2) A spun cylinder is one in which an end closure in the finished 
cylinder has been welded by the spinning process.
    (3) A plugged cylinder is one in which a permanent closure in the 
bottom of a finished cylinder has been effected by a plug.
    (4) As a safety precaution, if the manufacturer elects to make this 
test before the hydrostatic test, he should design his apparatus so that 
the pressure is applied to the smallest area practicable, around the 
point of closure, and so as to use the smallest possible volume of air 
or gas.
    (n) Rejected cylinders. Reheat treatment of rejected cylinders is 
authorized. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding or spinning is not authorized. Spun 
cylinders rejected under the provisions of paragraph (m) of this section 
may be removed from the spun cylinder category by drilling to remove 
defective material, tapping and plugging.
    (o) Marking. Markings may be stamped into the sidewalls of cylinders 
having a service pressure of 150 psig if all of the following conditions 
are met:
    (1) Wall stress at test pressure may not exceed 24,000 psi.
    (2) Minimum wall thickness must be not less than 0.090 inch.
    (3) Depth of stamping must be no greater than 15 percent of the 
minimum wall thickness, but may not exceed 0.015 inch.
    (4) Maximum outside diameter of cylinder may not exceed 5 inches.
    (5) Carbon content of cylinder may not exceed 0.25 percent. If the 
carbon content exceeds 0.25 percent, the complete cylinder must be 
normalized after stamping.
    (6) Stamping must be adjacent to the top head.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended by 66 FR 45185, 
45386-45388, Aug. 28, 2001; 67 FR 51652, Aug. 8, 2002; 68 FR 75748, Dec. 
31, 2003]



Sec. 178.39  Specification 3BN seamless nickel cylinders.

    (a) Type, size and service pressure. A DOT 3BN cylinder is a 
seamless nickel cylinder with a water capacity (nominal) not over 125 
pounds water capacity (nominal) and a service pressure at least 150 to 
not over 500 psig.
    (b) Nickel. The percentage of nickel plus cobalt must be at least 
99.0 percent.
    (c) Identification of material. The material must be identified by 
any suitable method except that plates and billets for hot-drawn 
cylinders must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. Cylinders closed in by spinning 
process are not authorized.

[[Page 27]]

    (e) Welding or brazing. Welding or brazing for any purpose 
whatsoever is prohibited except that welding is authorized for the 
attachment of neckrings and footrings which are nonpressure parts, and 
only to the tops and bottoms of cylinders. Neckrings and footrings must 
be of weldable material, the carbon content of which may not exceed 0.25 
percent. Nickel welding rod must be used.
    (f) Wall thickness. The wall stress may not exceed 15,000 psi. A 
minimum wall thickness of 0.100 inch is required for any cylinder over 5 
inches in outside diameter. Wall stress calculation must be made by 
using the following formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test or 450 psig 
          whichever is the greater;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. The completed cylinders must be uniformly and 
properly heat-treated prior to tests.
    (h) Openings in cylinders and connections (valves, fuse plugs, etc.) 
for those openings. Threads conforming to the following are required on 
openings:
    (1) Threads must be clean cut, even, without checks, and to gauge.
    (2) Taper threads, when used, to be of length not less than as 
specified for American Standard taper pipe threads.
    (3) Straight threads having at least 6 engaged threads are 
authorized. Straight threads must have a tight fit and a calculated 
shear strength of at least 10 times the test pressure of the cylinder. 
Gaskets, adequate to prevent leakage, are required.
    (i) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test, as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy either of 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Each cylinder must be tested to at least 2 times service 
pressure.
    (j) Flattening test. A flattening test must be performed on one 
cylinder taken at random out of each lot of 200 or less, by placing the 
cylinder between wedge shaped knife edges having a 60[deg] included 
angle, rounded to \1/2\-inch radius. The longitudinal axis of the 
cylinder must be at a 90-degree angle to knife edges during the test. 
For lots of 30 or less, flattening tests are authorized to be made on a 
ring at least 8 inches long cut from each cylinder and subjected to same 
heat treatment as the finished cylinder.
    (k) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material, as follows:
    (1) The test is required on 2 specimens cut from 1 cylinder taken at 
random out of each lot of 200 or less. For lots of 30 or less, physical 
tests are authorized to be made on a ring at least 8 inches long cut 
from each cylinder and subjected to same heat treatment as the finished 
cylinder.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width of not over 1\1/2\ 
inches, a gauge length of 2 inches with a width of not over 1\1/2\ 
inches, or a gauge length of at least 24 times the thickness with a 
width not over 6 times thickness is authorized when a cylinder wall is 
not over \3/16\ inch thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within one inch of each end of the reduced 
section.
    (iii) When size of cylinder does not permit securing straight 
specimens,

[[Page 28]]

the specimens may be taken in any location or direction and may be 
straightened or flattened cold, by pressure only, not by blows. When 
specimens are so taken and prepared, the inspector's report must show in 
connection with record of physical tests detailed information in regard 
to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi, and the 
strain indicator reading must be set at the calculated corresponding 
strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (l) Acceptable results for physical and flattening tests. Either of 
the following is an acceptable result:
    (1) An elongation of at least 40 percent for a 2 inch gauge length 
or at least 20 percent in other cases and yield point not over 50 
percent of tensile strength. In this instance, the flattening test is 
not required.
    (2) An elongation of at least 20 percent for a 2 inch gauge length 
or 10 percent in other cases and a yield point not over 50 percent of 
tensile strength. Flattening is required, without cracking, to 6 times 
the wall thickness.
    (m) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinders. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding is not authorized.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended by 66 FR 45185, 
45386, 45388, Aug. 28, 2001; 67 FR 51652, Aug. 8, 2002; 68 FR 75748, 
Dec. 31, 2003]



Sec. 178.42  Specification 3E seamless steel cylinders.

    (a) Type, size, and service pressure. A DOT 3E cylinder is a 
seamless steel cylinder with an outside diameter not greater than 2 
inches nominal, a length less than 2 feet and a service pressure of 
1,800 psig.
    (b) Steel. Open-hearth or electric steel of uniform quality must be 
used. Content percent may not exceed the following: Carbon, 0.55; 
phosphorus, 0.045; sulphur, 0.050.
    (c) Identification of steel. Materials must be identified by any 
suitable method.
    (d) Manufacture. Cylinders must be manufactured by best appliances 
and methods. No defect is permitted that is likely to weaken the 
finished cylinder appreciably. A reasonably smooth and uniform surface 
finish is required. The thickness of the spun bottom is, under no 
condition, to be less than two times the minimum wall thickness of the 
cylindrical shell; such bottom thickness must be measured within an area 
bounded by a line representing the points of contact between the 
cylinder and floor when the cylinder is in a vertical position.
    (e) Openings in cylinders and connections (valves, fuse plugs, etc.) 
for those openings. Threads conforming to the following are required on 
openings.
    (1) Threads must be clean cut, even, without checks, and to gauge.
    (2) Taper threads, when used, must be of length not less than as 
specified for American Standard taper pipe threads.
    (3) Straight threads having at least 4 engaged threads are 
authorized. Straight threads must have a tight fit and a calculated 
shear strength of at least 10 times the test pressure of the

[[Page 29]]

cylinder. Gaskets, adequate to prevent leakage, are required.
    (f) Hydrostatic test. Cylinders must be tested as follows:
    (1) One cylinder out of each lot of 500 or less must be subjected to 
a hydrostatic pressure of 6,000 psig or higher.
    (2) The cylinder referred to in paragraph (f)(1) of this section 
must burst at a pressure higher than 6,000 psig without fragmenting or 
otherwise showing lack of ductility, or must hold a pressure of 12,000 
psig for 30 seconds without bursting. In which case, it must be 
subjected to a flattening test without cracking to six times wall 
thickness between knife edges, wedge shaped 60 degree angle, rounded out 
to a \1/2\ inch radius. The inspector's report must be suitably changed 
to show results of latter alternate and flattening test.
    (3) Other cylinders must be examined under pressure of at least 
3,000 psig and not to exceed 4,500 psig and show no defect. Cylinders 
tested at a pressure in excess of 3,600 psig must burst at a pressure 
higher than 7,500 psig when tested as specified in paragraph (f)(2) of 
this section. The pressure must be maintained for at least 30 seconds 
and sufficiently longer to ensure complete examination.
    (g) Leakage test. All spun cylinders and plugged cylinders must be 
tested for leakage by gas or air pressure after the bottom has been 
cleaned and is free from all moisture subject to the following 
conditions and limitations:
    (1) A pressure, approximately the same as but not less than the 
service pressure, must be applied to one side of the finished bottom 
over an area of at least \1/16\ of the total area of the bottom but not 
less than \3/4\ inch in diameter, including the closure, for at least 
one minute, during which time the other side of the bottom exposed to 
pressure must be covered with water and closely examined for indications 
of leakage. Accept as provided in paragraph (h) of this section, a 
cylinder must be rejected if there is any leakage.
    (2) A spun cylinder is one in which an end closure in the finished 
cylinder has been welded by the spinning process.
    (3) A plugged cylinder is one in which a permanent closure in the 
bottom of a finished cylinder has been effected by a plug.
    (4) As a safety precaution, if the manufacturer elects to make this 
test before the hydrostatic test, the manufacturer shall design the test 
apparatus so that the pressure is applied to the smallest area 
practicable, around the point of closure, and so as to use the smallest 
possible volume of air or gas.
    (h) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinders. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding or spinning is not authorized. Spun 
cylinders rejected under the provisions of paragraph (g) of this section 
may be removed from the spun cylinder category by drilling to remove 
defective material, tapping and plugging.
    (i) Marking. Markings required by Sec. 178.35 must be stamped 
plainly and permanently on the shoulder, top head, neck or sidewall of 
each cylinder.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended by 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.44  Specification 3HT seamless steel cylinders for 
aircraft use.

    (a) Type, size and service pressure. A DOT 3HT cylinder is a 
seamless steel cylinder with a water capacity (nominal) of not over 150 
pounds and a service pressure of at least 900 psig.
    (b) Authorized steel. Open hearth or electric furnace steel of 
uniform quality must be used. A heat of steel made under the 
specifications listed in Table 1 in this paragraph (b), a check chemical 
analysis that is slightly out of the specified range is acceptable, if 
satisfactory in all other respects, provided the tolerances shown in 
Table 2 in this paragraph (b) are not exceeded. The maximum grain size 
shall be 6 or finer. The grain size must be determined in accordance 
with ASTM E 112-88 (IBR, see Sec. 171.7 of this subchapter). Steel of 
the following chemical analysis is authorized:

                      Table 1--Authorized Materials
------------------------------------------------------------------------
              Designation                      AISI 4130 (percent)
------------------------------------------------------------------------
Carbon.................................  0.28/0.33
Manganese..............................  0.40/0.60
Phosphorus.............................  0.040 maximum
Sulfur.................................  0.040 maximum

[[Page 30]]

 
Silicon................................  0.15/0.35
Chromium...............................  0.80/1.10
Molybdenum.............................  0.15/0.25
------------------------------------------------------------------------


                   Table 2--Check Analysis Tolerances
------------------------------------------------------------------------
                                                           Tolerance
                                                      (percent) over the
                                                       maximum limit or
                                                       under the minimum
           Element                Limit or maximum           limit
                                specified (percent)  -------------------
                                                        Under     Over
                                                       minimum   maximum
                                                        limit     limit
------------------------------------------------------------------------
Carbon.......................  Over 0.15 to 0.40           .03       .04
                                incl.
Manganese....................  To 0.60 incl.........       .03       .03
Phosphorus\1\................  All ranges...........  ........       .01
Sulphur......................  All ranges...........  ........       .01
Silicon......................  To 0.30 incl.........       .02       .03
                               Over 0.30 to 1.00           .05       .05
                                incl.
Chromium.....................  To 0.90 incl.........       .03       .03
                               Over 0.90 to 2.10           .05       .05
                                incl.
Molybdenum...................  To 0.20 incl.........       .01       .01
                               Over 0.20 to 0.40           .02       .02
                                incl.
------------------------------------------------------------------------
\1\ Rephosphorized steels not subject to check analysis for phosphorus.

    (c) Identification of material. Material must be identified by any 
suitable method. Steel stamping of heat identifications may not be made 
in any area which will eventually become the side wall of the cylinder. 
Depth of stamping may not encroach upon the minimum prescribed wall 
thickness of the cylinder.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No fissure or other defect is permitted 
that is likely to weaken the finished container appreciably. The general 
surface finish may not exceed a roughness of 250 RMS. Individual 
irregularities such as draw marks, scratches, pits, etc., should be held 
to a minimum consistent with good high stress pressure vessel 
manufacturing practices. If the cylinder is not originally free of such 
defects or does not meet the finish requirements, the surface may be 
machined or otherwise treated to eliminate these defects. The point of 
closure of cylinders closed by spinning may not be less than two times 
the prescribed wall thickness of the cylindrical shell. The cylinder end 
contour must be hemispherical or ellipsoidal with a ratio of major-to-
minor axis not exceeding two to one and with the concave side to 
pressure.
    (e) Welding or brazing. Welding or brazing for any purpose 
whatsoever is prohibited, except that welding by spinning is permitted 
to close the bottom of spun cylinders. Machining or grinding to produce 
proper surface finish at point of closure is required.
    (f) Wall thickness. (1) Minimum wall thickness for any cylinder must 
be 0.050 inch. The minimum wall thickness must be such that the wall 
stress at the minimum specified test pressure may not exceed 75 percent 
of the minimum tensile strength of the steel as determined from the 
physical tests required in paragraph (m) of this section and may not be 
over 105,000 psi.
    (2) Calculations must be made by the formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = Wall stress in psi;
P = Minimum test pressure prescribed for water jacket test;
D = Outside diameter in inches;
d = Inside diameter in inches.

    (3) Wall thickness of hemispherical bottoms only permitted to 90 
percent of minimum wall thickness of cylinder sidewall but may not be 
less than 0.050 inch. In all other cases, thickness to be no less than 
prescribed minimum wall.
    (g) Heat treatment. The completed cylinders must be uniformly and 
properly heated prior to tests. Heat treatment of the cylinders of the 
authorized analysis must be as follows:
    (1) All cylinders must be quenched by oil, or other suitable medium.
    (2) The steel temperature on quenching must be that recommended for 
the steel analysis, but may not exceed 1750 [deg]F.
    (3) The steel must be tempered at a temperature most suitable for 
the particular steel analysis but not less than 850 [deg]F.
    (4) All cylinders must be inspected by the magnetic particle or dye 
penetrant method to detect the presence of quenching cracks. Any 
cylinder found to have a quenching crack must be rejected and may not be 
requalified.

[[Page 31]]

    (h) Openings in cylinders and connections (valves, fuse plugs, etc.) 
for those openings. Threads conforming to the following are required on 
openings:
    (1) Threads must be clean cut, even, without cracks, and to gauge.
    (2) Taper threads, when used, must be of length not less than as 
specified for National Gas Tapered Thread (NGT) as required by American 
Standard Compressed Gas Cylinder Valve Outlet and Inlet Connections.
    (3) Straight threads having at least 6 engaged threads are 
authorized. Straight threads must have a tight fit and a calculated 
shear stress of at least 10 times the test pressure of the cylinder. 
Gaskets, adequate to prevent leakage, are required.
    (i) Hydrostatic test. Each cylinder must withstand a hydrostatic 
test, as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. Pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy either of 1 percent of 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, which ever 
is the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Each cylinder must be tested to at least \5/3\ times service 
pressure.
    (j) Cycling tests. Prior to the initial shipment of any specific 
cylinder design, cyclic pressurization tests must have been performed on 
at least three representative samples without failure as follows:
    (1) Pressurization must be performed hydrostatically between 
approximately zero psig and the service pressure at a rate not in excess 
of 10 cycles per minute. Adequate recording instrumentation must be 
provided if equipment is to be left unattended for periods of time.
    (2) Tests prescribed in paragraph (j)(1) of this section must be 
repeated on one random sample out of each lot of cylinders. The cylinder 
may then be subjected to a burst test.
    (3) A lot is defined as a group of cylinders fabricated from the 
same heat of steel, manufactured by the same process and heat treated in 
the same equipment under the same conditions of time, temperature, and 
atmosphere, and may not exceed a quantity of 200 cylinders.
    (4) All cylinders used in cycling tests must be destroyed.
    (k) Burst test. One cylinder taken at random out of each lot of 
cylinders must be hydrostatically tested to destruction.
    (l) Flattening test. A flattening test must be performed on one 
cylinder taken at random out of each lot of 200 or less, by placing the 
cylinder between wedge shaped knife edges having a 60[deg] included 
angle, rounded to \1/2\-inch radius. The longitudinal axis of the 
cylinder must be at a 90-degree angle to knife edges during the test. 
For lots of 30 or less, flattening tests are authorized to be made on a 
ring at least 8 inches long cut from each cylinder and subjected to same 
heat treatment as the finished cylinder.
    (m) Physical tests. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material, as follows:
    (1) Test is required on 2 specimens cut from 1 cylinder taken at 
random out of each lot of cylinders.
    (2) Specimens must conform to the following:
    (i) A gauge length of at least 24 times the thickness with a width 
not over six times the thickness. The specimen, exclusive of grip ends, 
may not be flattened. Grip ends may be flattened to within one inch of 
each end of the reduced section. When size of cylinder does not permit 
securing straight specimens, the specimens may be taken in any location 
or direction and may be straightened or flattened cold by pressure only, 
not by blows. When specimens are so taken and prepared, the inspector's 
report must show in

[[Page 32]]

connection with the record of physical tests detailed information in 
regard to such specimens.
    (ii) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length.
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi, the strain 
indicator reading being set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (n) Magnetic particle inspection. Inspection must be performed on 
the inside of each container before closing and externally on each 
finished container after heat treatment. Evidence of discontinuities, 
which in the opinion of a qualified inspector may appreciably weaken or 
decrease the durability of the cylinder, must be cause for rejection.
    (o) Leakage test. All spun cylinders and plugged cylinders must be 
tested for leakage by dry gas or dry air pressure after the bottom has 
been cleaned and is free from all moisture, subject to the following 
conditions and limitations:
    (1) Pressure, approximately the same as but not less than service 
pressure, must be applied to one side of the finished bottom over an 
area of at least \1/16\ of the total area of the bottom but not less 
than \3/4\ inch in diameter, including the closure, for at least one 
minute, during which time the other side of the bottom exposed to 
pressure must be covered with water and closely examined for indications 
of leakage. Except as provided in paragraph (q) of this section, a 
cylinder must be rejected if there is leakage.
    (2) A spun cylinder is one in which an end closure in the finished 
cylinder has been welded by the spinning process.
    (3) A plugged cylinder is one in which a permanent closure in the 
bottom of a finished cylinder has been effected by a plug.
    (4) As a safety precaution, if the manufacturer elects to make this 
test before the hydrostatic test, the manufacturer should design the 
test apparatus so that the pressure is applied to the smallest area 
practicable, around the point of closure, and so as to use the smallest 
possible volume of air or gas.
    (p) Acceptable results of tests. Results of the flattening test, 
physical tests, burst test, and cycling test must conform to the 
following:
    (1) Flattening required without cracking to ten times the wall 
thickness of the cylinder.
    (2) Physical tests:
    (i) An elongation of at least 6 percent for a gauge length of 24 
times the wall thickness.
    (ii) The tensile strength may not exceed 165,000 p.s.i.
    (3) The burst pressure must be at least \4/3\ times the test 
pressure.
    (4) Cycling-at least 10,000 pressurizations.
    (q) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinders. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding or spinning is not authorized. For 
each cylinder subjected to reheat treatment during original manufacture, 
sidewall measurements must be made to verify that the minimum sidewall 
thickness meets specification requirements after the final heat 
treatment.

[[Page 33]]

    (r) Marking. (1) Cylinders must be marked by low stress type steel 
stamping in an area and to a depth which will insure that the wall 
thickness measured from the root of the stamping to the interior surface 
is equal to or greater than the minimum prescribed wall thickness. 
Stamping must be permanent and legible. Stamping on side wall not 
authorized.
    (2) The rejection elastic expansion (REE), in cubic cm (cc), must be 
marked on the cylinder near the date of test. The REE for a cylinder is 
1.05 times its original elastic expansion.
    (3) Name plates are authorized, provided that they can be 
permanently and securely attached to the cylinder. Attachment by either 
brazing or welding is not permitted. Attachment by soldering is 
permitted provided steel temperature does not exceed 500 [deg]F.
    (s) Inspector's report. In addition to the requirements of Sec. 
178.35, the inspector's report must indicate the rejection elastic 
expansion (REE), in cubic cm (cc).

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 62 FR 51561, 
Oct. 1, 1997; 65 FR 58631, Sept. 29, 2000; 66 FR 45385, Aug. 28, 2001; 
67 FR 51652, Aug. 8, 2002; 68 FR 75748, 75749, Dec. 31, 2003]



Sec. 178.45  Specification 3T seamless steel cylinder.

    (a) Type, size, and service pressure. A DOT 3T cylinder is a 
seamless steel cylinder with a minimum water capacity of 1,000 pounds 
and a minimum service pressure of 1,800 psig. Each cylinder must have 
integrally formed heads concave to pressure at both ends. The inside 
head shape must be hemispherical, ellipsoidal in which the major axis is 
two times the minor axis, or a dished shape falling within these two 
limits. Permanent closures formed by spinning are prohibited.
    (b) Material, steel. Only open hearth, basic oxygen, or electric 
furnace process steel of uniform quality is authorized. The steel 
analysis must conform to the following:

                           Analysis Tolerances
------------------------------------------------------------------------
                                                         Check Analysis
             Element                  Ladle analysis   -----------------
                                                         Under     Over
------------------------------------------------------------------------
Carbon...........................  0.35 to 0.50.......     0.03     0.04
Manganese........................  0.75 to 1.05.......     0.04     0.04
Phosphorus (max).................  0.035..............  .......     0.01
Sulphur (max)....................  0.04...............  .......     0.01
Silicon..........................  0.15 to 0.35.......     0.02     0.03
Chromium.........................  0.80 to 1.15.......     0.05     0.05
Molybdenum.......................  0.15 to 0.25.......     0.02     0.02
------------------------------------------------------------------------

    (1) A heat of steel made under the specifications in the table in 
this paragraph (b), the ladle analysis of which is slightly out of the 
specified range, is acceptable if satisfactory in all other aspects. 
However, the check analysis tolerances shown in the table in this 
paragraph (b) may not be exceeded except as approved by the Department.
    (2) Material with seams, cracks, laminations, or other injurious 
defects is not permitted.
    (3) Material used must be identified by any suitable method.
    (c) Manufacture. General manufacturing requirements are as follows:
    (1) Surface finish must be uniform and reasonably smooth.
    (2) Inside surfaces must be clean, dry, and free of loose particles.
    (3) No defect of any kind is permitted if it is likely to weaken a 
finished cylinder.
    (4) If the cylinder surface is not originally free from the defects, 
the surface may be machined or otherwise treated to eliminate these 
defects provided the minimum wall thickness is maintained.
    (5) Welding or brazing on a cylinder is not permitted.
    (d) Wall thickness. The minimum wall thickness must be such that the 
wall stress at the minimum specified test pressure does not exceed 67 
percent of the minimum tensile strength of the steel as determined by 
the physical tests required in paragraphs (j) and (k) of this section. A 
wall stress of more than 90,500 p.s.i. is not permitted. The minimum 
wall thickness for any cylinder may not be less than 0.225 inch.
    (1) Calculation of the stress for cylinders must be made by the 
following formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = Wall stress in psi;

[[Page 34]]

P = Minimum test pressure, at least \5/3\ service pressure;
D = Outside diameter in inches;
d = Inside diameter in inches.

    (2) Each cylinder must meet the following additional requirement 
which assumes a cylinder horizontally supported at its two ends and 
uniformly loaded over its entire length. This load consists of the 
weight per inch of length of the straight cylindrical portion filled 
with water compressed to the specified test pressure. The wall thickness 
must be increased when necessary to meet this additional requirement:
    (i) The sum of two times the maximum tensile stress in the bottom 
fibers due to bending (see paragraph (d)(2)(ii) of this section), plus 
the maximum tensile stress in the same fibers due to hydrostatic testing 
(see paragraph (d)(2)(iii) of this section) may not exceed 80 percent of 
the minimum yield strength of the steel at this maximum stress.
    (ii) The following formula must be used to calculate the maximum 
tensile stress due to bending:

S = Mc / I

Where:

S = Tensile stress in psi;
M = Bending moment in inch-pounds (wl\2\/8);
I = Moment of inertia--0.04909 (D\4\-d\4\) in inches fourth;
c = Radius (D/2) of cylinder in inches;
w = Weight per inch of cylinder filled with water;
l = Length of cylinder in inches;
D = Outside diameter in inches;
d = Inside diameter in inches.

    (iii) The following formula must be used to calculate the maximum 
longitudinal tensile stress due to hydrostatic test pressure:

S = A1 P / A2

Where:

S = Tensile stress in psi;
A1 = Internal area in cross section of cylinder in square 
          inches;
P = Hydrostatic test pressure-psig;
A2 = Area of metal in cross section of cylinder in square 
          inches.

    (e) Heat treatment. Each completed cylinder must be uniformly and 
properly heat treated prior to testing, as follows:
    (1) Each cylinder must be heated and held at the proper temperature 
for at least one hour per inch of thickness based on the maximum 
thickness of the cylinder and then quenched in a suitable liquid medium 
having a cooling rate not in excess of 80 percent of water. The steel 
temperature on quenching must be that recommended for the steel 
analysis, but it must never exceed 1750 [deg]F.
    (2) After quenching, each cylinder must be reheated to a temperature 
below the transformation range but not less than 1050 [deg]F., and must 
be held at this temperature for at least one hour per inch of thickness 
based on the maximum thickness of the cylinder. Each cylinder must then 
be cooled under conditions recommended for the steel.
    (f) Openings. Openings in cylinders must comply with the following:
    (1) Openings are permitted on heads only.
    (2) The size of any centered opening in a head may not exceed one 
half the outside diameter of the cylinder.
    (3) Openings in a head must have ligaments between openings of at 
least three times the average of their hole diameter. No off-center 
opening may exceed 2.625 inches in diameter.
    (4) All openings must be circular.
    (5) All openings must be threaded. Threads must be in compliance 
with the following:
    (i) Each thread must be clean cut, even, without any checks, and to 
gauge.
    (ii) Taper threads, when used, must be the American Standard Pipe 
thread (NPT) type and must be in compliance with the requirements of NBS 
Handbook H-28 (IBR, see Sec. 171.7 of this subchapter).
    (iii) Taper threads conforming to National Gas Taper thread (NGT) 
standards must be in compliance with the requirements of NBS Handbook H-
28.
    (iv) Straight threads conforming with National Gas Straight thread 
(NGS) standards are authorized. These threads must be in compliance with 
the requirements of NBS Handbook H-28.
    (g) Hydrostatic test. Each cylinder must be tested at an internal 
pressure by the water jacket method or other

[[Page 35]]

suitable method, conforming to the following requirements:
    (1) The testing apparatus must be operated in a manner that will 
obtain accurate data. Any pressure gauge used must permit reading to an 
accuracy of one percent. Any expansion gauge used must permit reading of 
the total expansion to an accuracy of one percent.
    (2) Any internal pressure applied to the cylinder after heat 
treatment and before the official test may not exceed 90 percent of the 
test pressure.
    (3) The pressure must be maintained sufficiently long to assure 
complete expansion of the cylinder. In no case may the pressure be held 
less than 30 seconds.
    (4) If, due to failure of the test apparatus, the required test 
pressure cannot be maintained, the test must be repeated at a pressure 
increased by 10 percent or 100 psig, whichever is lower or, the cylinder 
must be reheat treated.
    (5) Permanent volumetric expansion of the cylinder may not exceed 10 
percent of its total volumetric expansion at the required test pressure.
    (6) Each cylinder must be tested to at least \5/3\ times its service 
pressure.
    (h) Ultrasonic examination. After the hydrostatic test, the 
cylindrical section of each vessel must be examined in accordance with 
ASTM E 213 for shear wave and E 114 for straight beam (IBR, Standard see 
Sec. 171.7 of this subchapter). The equipment used must be calibrated 
to detect a notch equal to five percent of the design minimum wall 
thickness. Any discontinuity indication greater than that produced by 
the five percent notch must be cause for rejection of the cylinder, 
unless the discontinuity is repaired within the requirements of this 
specification.
    (i) Basic requirements for tension and Charpy impact tests. 
Cylinders must be subjected to a tension and Charpy impact as follows:
    (1) When the cylinders are heat treated in a batch furnace, two 
tension specimens and three Charpy impact specimens must be tested from 
one of the cylinders or a test ring from each batch. The lot size 
represented by these tests may not exceed 200 cylinders.
    (2) When the cylinders are heat treated in a continuous furnace, two 
tension specimens and three Charpy impact specimens must be tested from 
one of the cylinders or a test ring from each four hours or less of 
production. However, in no case may a test lot based on this production 
period exceed 200 cylinders.
    (3) Each specimen for the tension and Charpy impact tests must be 
taken from the side wall of a cylinder or from a ring which has been 
heat treated with the finished cylinders of which the specimens must be 
representative. The axis of the specimens must be parallel to the axis 
of the cylinder. Each cylinder or ring specimen for test must be of the 
same diameter, thickness, and metal as the finished cylinders they 
represent. A test ring must be at least 24 inches long with ends covered 
during the heat treatment process so as to simulate the heat treatment 
process of the finished cylinders it represents.
    (4) A test cylinder or test ring need represent only one of the 
heats in a furnace batch provided the other heats in the batch have 
previously been tested and have passed the tests and that such tests do 
not represent more than 200 cylinders from any one heat.
    (5) The test results must conform to the requirements specified in 
paragraphs (j) and (k) of this section.
    (6) When the test results do not conform to the requirements 
specified, the cylinders represented by the tests may be reheat treated 
and the tests repeated. Paragraph (i)(5) of this section applies to any 
retesting.
    (j) Basic conditions for acceptable physical testing. The following 
criteria must be followed to obtain acceptable physical test results:
    (1) Each tension specimen must have a gauge length of two inches 
with a width not exceeding one and one-half inches. Except for the grip 
ends, the specimen may not be flattened. The grip ends may be flattened 
to within one inch of each end of the reduced section.
    (2) A specimen may not be heated after heat treatment specified in 
paragraph (d) of this section.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gage length.
    (i) This yield strength must be determined by the ``offset'' method 
or the

[[Page 36]]

``extension under load'' method described in ASTM E 8 (IBR, see Sec. 
171.7 of this subchapter).
    (ii) For the ``extension under load'' method, the total strain (or 
extension under load) corresponding to the stress at which the 0.2 
percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gage length under 
appropriate load and adding thereto 0.2 percent of the gage length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. However, when the degree of accuracy of this method is 
questionable the entire stress-strain diagram must be plotted and the 
yield strength determined from the 0.2 percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set with the specimen under a stress of 12,000 p.s.i. and the strain 
indicator reading set at the calculated corresponding strain.
    (iv) The cross-head speed of the testing machine may not exceed \1/
8\ inch per minute during the determination of yield strength.
    (4) Each impact specimen must be Charpy V-notch type size 10 mm x 10 
mm taken in accordance with paragraph 11 of ASTM A 333 (IBR, see Sec. 
171.7 of this subchapter). When a reduced size specimen is used, it must 
be the largest size obtainable.
    (k) Acceptable physical test results. Results of physical tests must 
conform to the following:
    (1) The tensile strength may not exceed 155,000 p.s.i.
    (2) The elongation must be at least 16 percent for a two-inch gage 
length.
    (3) The Charpy V-notch impact properties for the three impact 
specimens which must be tested at 0 [deg]F may not be less than the 
values shown as follows:

------------------------------------------------------------------------
                                  Average value for    Minimum value (1
     Size of specimen (mm)          acceptance (3      specimen only of
                                     specimens)             the 3)
------------------------------------------------------------------------
10.0x10.0......................  25.0 ft. lbs......  20.0 ft. lbs.
10.0x7.5.......................  21.0 ft. lbs......  17.0 ft. lbs.
10.0x5.0.......................  17.0 ft. lbs......  14.0 ft. lbs.
------------------------------------------------------------------------

    (4) After the final heat treatment, each vessel must be hardness 
tested on the cylindrical section. The tensile strength equivalent of 
the hardness number obtained may not be more than 165,000 p.s.i. (Rc 
36). When the result of a hardness test exceeds the maximum permitted, 
two or more retests may be made; however, the hardness number obtained 
in each retest may not exceed the maximum permitted.
    (l) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinders. However, each reheat treated cylinder must subsequently pass 
all the prescribed tests. Repair by welding is not authorized.
    (m) Markings. Marking must be done by stamping into the metal of the 
cylinder. All markings must be legible and located on a shoulder.
    (n) Inspector's report. In addition to the requirements of Sec. 
178.35, the inspector's report for the physical test report, must 
indicate the average value for three specimens and the minimum value for 
one specimen for each lot number.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45385, 
43588, Aug. 28, 2001; 67 FR 51652, Aug. 8, 2002; 68 FR 48571, Aug. 14, 
2003; 68 FR 75748, 75749, Dec. 31, 2003]



Sec. 178.46  Specification 3AL seamless aluminum cylinders.

    (a) Size and service pressure. A DOT 3AL cylinder is a seamless 
aluminum cylinder with a maximum water capacity of 1000 pounds and 
minimum service pressure of 150 psig.
    (b) Authorized material and identification of material. The material 
of construction must meet the following conditions:
    (1) Starting stock must be cast stock or traceable to cast stock.
    (2) Material with seams, cracks, laminations, or other defects 
likely to weaken the finished cylinder may not be used.
    (3) Material must be identified by a suitable method that will 
identify the alloy, the aluminum producer's cast number, the solution 
heat treat batch number and the lot number.
    (4) The material must be of uniform quality. Only the following heat 
treatable aluminum alloys in table 1 and 2 are permitted as follows:

[[Page 37]]



         Table 1--Heat or Cast Analysis for Aluminum; Similar to ``Aluminum Association''\1\ Alloy 6061
                                    [CHEMICAL ANALYSIS IN WEIGHT PERCENT\2\]
----------------------------------------------------------------------------------------------------------------
                                                                                        Other
Si min/         Cu min/          Mg min/  Cr min/                                 ----------------
  max   Fe max    max    Mn max    max      max    Zn max  Ti max  Pb max  Bi max   each    total        A1
                                                                                     max     max
----------------------------------------------------------------------------------------------------------------
  0.4/     0.7    0.15/    0.15    0.8/     0.04/    0.25    0.15   0.005   0.005    0.05    0.15  Bal.
    0.8             0.4             1.2      0.35
----------------------------------------------------------------------------------------------------------------
\1\ The ``Aluminum Association'' refers to ``Aluminum Standards and Data 1993'', published by the Aluminum
  Association Inc.
\2\ Except for ``Pb'' and ``Bi'', the chemical composition corresponds with that of Table 1 of ASTM B 221 (IBR,
  see Sec. 171.7 of this subchapter) for Aluminum Association alloy 6061.


                                       Table 2--Mechanical Property Limits
----------------------------------------------------------------------------------------------------------------
                                                              Tensile strength--PSI          Elongation--percent
                                                    ----------------------------------------  minimum for 2 or 4D \1\
                                                      Ultimate--minimum    Yield--minimum       size specimen
----------------------------------------------------------------------------------------------------------------
6061-T6............................................              38,000              35,000                \2\14
----------------------------------------------------------------------------------------------------------------
\1\ ``D'' represents specimen diameters. When the cylinder wall is greater than \3/16\ inch thick, a retest
  without reheat treatment using the 4D size specimen is authorized if the test using the 2 inch size specimen
  fails to meet elongation requirements.
\2\ When cylinder wall is not over \3/16\-inch thick, 10 percent elongation is authorized when using a 24tx6t
  size test specimen.

    (5) All starting stock must be 100 percent ultrasonically inspected, 
along the length at right angles to the central axis from two positions 
at 90[deg] to one another. The equipment and continuous scanning 
procedure must be capable of detecting and rejecting internal defects 
such as cracks which have an ultrasonic response greater than that of a 
calibration block with a \5/64\-inch diameter flat bottomed hole.
    (6) Cast stock must have uniform equiaxed grain structure not to 
exceed 500 microns maximum.
    (7) Any starting stock not complying with the provisions of 
paragraphs (b)(1) through (b)(6) of this section must be rejected.
    (c) Manufacture. Cylinders must be manufactured in accordance with 
the following requirements:
    (1) Cylinder shells must be manufactured by the backward extrusion 
method and have a cleanliness level adequate to ensure proper 
inspection. No fissure or other defect is acceptable that is likely to 
weaken the finished cylinder below the design strength requirements. A 
reasonably smooth and uniform surface finish is required. If not 
originally free from such defects, the surface may be machined or 
otherwise conditioned to eliminate these defects.
    (2) Thickness of the cylinder base may not be less than the 
prescribed minimum wall thickness of the cylindrical shell. The cylinder 
base must have a basic torispherical, hemispherical, or ellipsoidal 
interior base configuration where the dish radius is no greater than 1.2 
times the inside diameter of the shell. The knuckle radius may not be 
less than 12 percent of the inside diameter of the shell. The interior 
base contour may deviate from the true torispherical, hemispherical or 
ellipsoidal configuration provided that--
    (i) Any areas of deviation are accompanied by an increase in base 
thickness;
    (ii) All radii of merging surfaces are equal to or greater than the 
knuckle radius;
    (iii) Each design has been qualified by successfully passing the 
cycling tests in this paragraph (c); and
    (iv) Detailed specifications of the base design are available to the 
inspector.
    (3) For free standing cylinders, the base thickness must be at least 
two times the minimum wall thickness along the line of contact between 
the cylinder base and the floor when the cylinders are in the vertical 
position.
    (4) Welding or brazing is prohibited.
    (5) Each new design and any significant change to any acceptable 
design must be qualified for production by testing prototype samples as 
follows:
    (i) Three samples must be subjected to 100,000 pressure reversal 
cycles between zero and service pressure or 10,000 pressure reversal 
cycles between zero and test pressure, at a rate not in

[[Page 38]]

excess of 10 cycles per minute without failure.
    (ii) Three samples must be pressurized to destruction and failure 
may not occur at less than 2.5 times the marked cylinder service 
pressure. Each cylinder must remain in one piece. Failure must initiate 
in the cylinder sidewall in a longitudinal direction. Rate of 
pressurization may not exceed 200 psig per second.
    (6) In this specification ``significant change'' means a 10 percent 
or greater change in cylinder wall thickness, service pressure, or 
diameter; a 30 percent or greater change in water capacity or base 
thickness; any change in material; over 100 percent increase in size of 
openings; or any change in the number of openings.
    (d) Wall thickness. The minimum wall thickness must be such that the 
wall stress at the minimum specified test pressure will not exceed 80 
percent of the minimum yield strength nor exceed 67 percent of the 
minimum ultimate tensile strength as verified by physical tests in 
paragraph (i) of this section. The minimum wall thickness for any 
cylinder with an outside diameter greater than 5 inches must be 0.125 
inch. Calculations must be made by the following formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = Wall stress in psi;
P = Prescribed minimum test pressure in psig (see paragraph (g) of this 
          section);
D = Outside diameter in inches; and
d = Inside diameter in inches.

    (e) Openings. Openings must comply with the following requirements:
    (1) Openings are permitted in heads only.
    (2) The size of any centered opening in a head may not exceed one-
half the outside diameter of the cylinder.
    (3) Other openings are permitted in the head of a cylinder if:
    (i) Each opening does not exceed 2.625 inches in diameter, or one-
half the outside diameter of the cylinder; whichever is less;
    (ii) Each opening is separated from each other by a ligament; and
    (iii) Each ligament which separates two openings must be at least 
three times the average of the diameters of the two openings.
    (4) All openings must be circular.
    (5) All openings must be threaded. Threads must comply with the 
following:
    (i) Each thread must be clean cut, even, without checks, and to 
gauge.
    (ii) Taper threads, when used, must conform to one of the following:
    (A) American Standard Pipe Thread (NPT) type, conforming to the 
requirements of NBS Handbook H-28 (IBR, see Sec. 171.7 of this 
subchapter);
    (B) National Gas Taper Thread (NGT) type, conforming to the 
requirements of NBS Handbook H-28; or
    (C) Other taper threads conforming to other standards may be used 
provided the length is not less than that specified for NPT threads.
    (iii) Straight threads, when used, must conform to one of the 
following:
    (A) National Gas Straight Thread (NGS) type, conforming to the 
requirements of NBS Handbook H-28;
    (B) Unified Thread (UN) type, conforming to the requirements of NBS 
Handbook H-28;
    (C) Controlled Radius Root Thread (UN) type, conforming to the 
requirements of NBS Handbook H-28; or
    (D) Other straight threads conforming to other recognized standards 
may be used provided that the requirements in paragraph (e)(5)(iv) of 
this section are met.
    (iv) All straight threads must have at least 6 engaged threads, a 
tight fit, and a factor of safety in shear of at least 10 at the test 
pressure of the cylinder. Shear stress must be calculated by using the 
appropriate thread shear area in accordance with NBS Handbook H-28.
    (f) Heat treatment. Prior to any test, all cylinders must be 
subjected to a solution heat treatment and aging treatment appropriate 
for the aluminum alloy used.
    (g) Hydrostatic test. Each cylinder must be subjected to an internal 
test pressure using the water jacket equipment and method or other 
suitable equipment and method and comply with the following 
requirements:
    (1) The testing apparatus must be operated in a manner so as to 
obtain accurate data. The pressure gauge used

[[Page 39]]

must permit reading to an accuracy of one percent. The expansion gauge 
must permit reading the total expansion to an accuracy of either one 
percent or 0.1 cubic centimeter.
    (2) The test pressure must be maintained for a sufficient period of 
time to assure complete expansion of the cylinder. In no case may the 
pressure be held less than 30 seconds. If, due to failure of the test 
apparatus, the required test pressure cannot be maintained, the test may 
be repeated at a pressure increased by 10 percent or 100 psig, whichever 
is lower. If the test apparatus again fails to maintain the test 
pressure, the cylinder being tested must be rejected. Any internal 
pressure applied to the cylinder before any official test may not exceed 
90 percent of the test pressure.
    (3) The minimum test pressure is the greatest of the following:
    (i) 450 psig regardless of service pressure;
    (ii) Two times the service pressure for cylinders having service 
pressure less than 500 psig; or
    (iii) Five-thirds times the service pressure for cylinders having a 
service pressure of at least 500 psig.
    (4) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (h) Flattening test. One cylinder taken at random out of each lot 
must be subjected to a flattening test as follows:
    (1) The test must be between knife edges, wedge shaped, having a 
60[deg] included angle, and rounded in accordance with the following 
table. The longitudinal axis of the cylinder must be at an angle 90[deg] 
to the knife edges during the test. The flattening test table is as 
follows:

                     Table 3--Flattening Test Table
------------------------------------------------------------------------
                                                                 Radius
               Cylinder wall thickness in inches                   in
                                                                 inches
------------------------------------------------------------------------
Under .150....................................................      .500
.150 to .249..................................................      .875
.250 to .349..................................................     1.500
.350 to .449..................................................     2.125
.450 to .549..................................................     2.750
.550 to .649..................................................     3.500
.650 to .749..................................................     4.125
------------------------------------------------------------------------

    (2) An alternate bend test in accordance with ASTM E 290 using a 
mandrel diameter not more than 6 times the wall thickness is authorized 
to qualify lots that fail the flattening test of this section without 
reheat treatment. If used, this test must be performed on two samples 
from one cylinder taken at random out of each lot of 200 cylinders or 
less.
    (3) Each test cylinder must withstand flattening to nine times the 
wall thickness without cracking. When the alternate bend test is used, 
the test specimens must remain uncracked when bent inward around a 
mandrel in the direction of curvature of the cylinder wall until the 
interior edges are at a distance apart not greater than the diameter of 
the mandrel.
    (i) Mechanical properties test. Two test specimens cut from one 
cylinder representing each lot of 200 cylinders or less must be 
subjected to the mechanical properties test, as follows:
    (1) The results of the test must conform to at least the minimum 
acceptable mechanical property limits for aluminum alloys as specified 
in paragraph (b) of this section.
    (2) Specimens must be 4D bar or gauge length 2 inches with width not 
over 1\1/2\ inch taken in the direction of extrusion approximately 
180[deg] from each other; provided that gauge length at least 24 times 
thickness with width not over 6 times thickness is authorized, when 
cylinder wall is not over \3/16\ inch thick. The specimen, exclusive of 
grip ends, may not be flattened. Grip ends may be flattened to within 
one inch of each end of the reduced section. When the size of the 
cylinder does not permit securing straight specimens, the specimens may 
be taken in any location or direction and may be straightened or 
flattened cold by pressure only, not by blows. When such specimens are 
used, the inspector's report must show that the specimens were so taken 
and prepared. Heating of specimens for any purpose is forbidden.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length.
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM B 
557 (IBR, see Sec. 171.7 of this subchapter).

[[Page 40]]

    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
10,000,000 psi. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 6,000 psi, the strain 
indicator reading being set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (j) Rejected cylinder. Reheat treatment of rejected cylinders is 
authorized one time. Subsequent thereto, cylinders must pass all 
prescribed tests to be acceptable.
    (k) Duties of inspector. In addition to the requirements of Sec. 
178.35, the inspector shall:
    (1) Verify compliance with the provisions of paragraph (b) of this 
section by:
    (i) Performing or witnessing the performance of the chemical 
analyses on each melt or cast lot or other unit of starting material; or
    (ii) Obtaining a certified chemical analysis from the material or 
cylinder manufacturer for each melt, or cast of material; or
    (iii) Obtaining a certified check analysis on one cylinder out of 
each lot of 200 cylinders or less, if a certificate containing data to 
indicate compliance with the material specification is obtained.
    (2) The inspector shall verify ultrasonic inspection of all material 
by inspection or by obtaining the material producer's certificate of 
ultrasonic inspection. Ultrasonic inspection must be performed or 
verified as having been performed in accordance with paragraph (c) of 
this section.
    (3) The inspector must also determine that each cylinder complies 
with this specification by:
    (i) Selecting the samples for check analyses performed by other than 
the material producer;
    (ii) Verifying that the prescribed minimum thickness was met by 
measuring or witnessing the measurement of the wall thickness; and
    (iii) Verifying that the identification of material is proper.
    (4) Prior to initial production of any design or design change, 
verify that the design qualification tests prescribed in paragraph 
(c)(6) of this section have been performed with acceptable results.
    (l) Definitions. (1) In this specification, a ``lot'' means a group 
of cylinders successively produced having the same:
    (i) Size and configuration;
    (ii) Specified material of construction;
    (iii) Process of manufacture and heat treatment;
    (iv) Equipment of manufacture and heat treatment; and
    (v) Conditions of time, temperature and atmosphere during heat 
treatment.
    (2) In no case may the lot size exceed 200 cylinders, but any 
cylinder processed for use in the required destructive physical testing 
need not be counted as being one of the 200.
    (m) Inspector's report. In addition to the information required by 
Sec. 178.35, the record of chemical analyses must also include the 
alloy designation, and applicable information on iron, titanium, zinc, 
magnesium and any other applicable element used in the construction of 
the cylinder.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386-
45388, Aug. 28, 2001; 67 FR 51652, Aug. 8, 2002; 68 FR 75749, Dec. 31, 
2003]



Sec. 178.47  Specification 4DS welded stainless steel cylinders for
aircraft use.

    (a) Type, size, and service pressure. A DOT 4DS cylinder is either a 
welded stainless steel sphere (two seamless hemispheres) or 
circumferentially welded cylinder both with a water capacity of not over 
100 pounds and a

[[Page 41]]

service pressure of at least 500 but not over 900 psig.
    (b) Steel. Types 304, 321 and 347 stainless steel are authorized 
with proper welding procedure. A heat of steel made under the 
specifications in table 1 in this paragraph (b), check chemical analysis 
of which is slightly out of the specified range, is acceptable, if 
satisfactory in all other respects, provided the tolerances shown in 
table 2 in this paragraph (b) are not exceeded, except as approved by 
Associate Administrator. The following chemical analyses are authorized:

                                          Table 1--Authorized Materials
----------------------------------------------------------------------------------------------------------------
                                                                   Stainless steels
                                    ----------------------------------------------------------------------------
                                            304 (percent)               321 (percent)           347 (percent)
----------------------------------------------------------------------------------------------------------------
Carbon (max).......................  0.08                        0.08                        0.08
Manganese (max)....................  2.00                        2.00                        2.00
Phosphorus (max)...................  .030                        .030                        .030
Sulphur (max)......................  .030                        .030                        .030
Silicon (max)......................  .75                         .75                         .75
Nickel.............................  8.0/11.0                    9.0/13.0                    9.0/13.0
Chromium...........................  18.0/20.0                   17.0/20.0                   17.0/20.0
Molybdenum
Titanium...........................  ..........................  (\1\)
Columbium..........................  ..........................  ..........................  (\2\)
----------------------------------------------------------------------------------------------------------------
\1\ Titanium may not be more than 5C and not more than 0.60%.
\2\ Columbium may not be less than 10C and not more than 1.0%.


                                       Table 2--Check Analysis Tolerances
----------------------------------------------------------------------------------------------------------------
                                                                                        Tolerance (percent) over
                                                                                          the maximum limit or
                                                                                         under the minimum limit
            Element                       Limit or maximum specified (percent)         -------------------------
                                                                                           Under         Over
                                                                                          minimum      maximum
                                                                                           limit        limit
----------------------------------------------------------------------------------------------------------------
Carbon.........................  To 0.15 incl.........................................         0.01         0.01
Manganese......................  Over 1.15 to 2.50 incl...............................         0.05         0.05
Phosphorus\1\..................  All ranges...........................................  ...........          .01
Sulphur........................  All ranges...........................................  ...........          .01
Silicon........................  Over 0.30 to 1.00 incl...............................          .05          .05
Nickel.........................  Over 5.30 to 10.00 incl..............................          .10          .10
                                 Over 10.00 to 14.00 incl.............................          .15          .15
Chromium.......................  Over 15.00 to 20.00 incl.............................          .20          .20
Titanium.......................  All ranges...........................................          .05          .05
Columbium......................  All ranges...........................................          .05          .05
----------------------------------------------------------------------------------------------------------------
\1\Rephosphorized steels not subject to check analysis for phosphorus.

    (c) Identification of material. Materials must be identified by any 
suitable method.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably, a reasonably smooth and 
uniform surface finish is required. No abrupt change in wall thickness 
is permitted. Welding procedures and operators must be qualified in 
accordance with CGA Pamphlet C-3 (IBR, see Sec. 171.7 of this 
subchapter). All seams of the sphere or cylinder must be fusion welded. 
Seams must be of the butt type and means must be provided for 
accomplishing complete penetration of the joint.
    (e) Attachments. Attachments to the container are authorized by 
fusion welding provided that such attachments are made of weldable 
stainless steel in accordance with paragraph (b) of this section.
    (f) Wall thickness. The minimum wall thickness must be such that the 
wall stress at the minimum specified test pressure may not be over 
60,000 psig. A minimum wall thickness of 0.040 inch is required for any 
diameter container. Calculations must be made by the following formulas:

[[Page 42]]

    (1) Calculation for sphere must be made by the formula:


S = PD / 4tE

Where:

S = Wall stress in psi;
P = Test pressure prescribed for water jacket test, i.e., at least two 
          times service pressure, in psig;
D = Outside diameter in inches;
t = Minimum wall thickness in inches;
E = 0.85 (provides 85 percent weld efficiency factor which must be 
          applied in the girth weld area and heat zones which zone must 
          extend a distance of 6 times wall thickness from center of 
          weld);
E = 1.0 (for all other areas).

    (2) Calculation for a cylinder must be made by the formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = Wall stress in psi;
P = Test pressure prescribed for water jacket test, i.e., at least two 
          times service pressure, in psig;
D = Outside diameter in inches;
d = Inside diameter in inches.

    (g) Heat treatment. The seamless hemispheres and cylinders may be 
stress relieved or annealed for forming. Welded container must be stress 
relieved at a temperature of 775 [deg]F 25[deg] 
after process treatment and before hydrostatic test.
    (h) Openings in container. Openings must comply with the following:
    (1) Each opening in the container must be provided with a fitting, 
boss or pad of weldable stainless steel securely attached to the 
container by fusion welding.
    (2) Attachments to a fitting, boss, or pad must be adequate to 
prevent leakage. Threads must comply with the following:
    (i) Threads must be clean cut, even, without checks, and tapped to 
gauge.
    (ii) Taper threads to be of length not less than as specified for 
American Standard taper pipe threads.
    (iii) Straight threads having at least 4 engaged threads, to have 
tight fit and calculated shear strength at least 10 times the test 
pressure of the container; gaskets required, adequate to prevent 
leakage.
    (i) Process treatment. Each container must be hydraulically 
pressurized in a water jacket to at least 100 percent, but not more than 
110 percent, of the test pressure and maintained at this pressure for a 
minimum of 3 minutes. Total and permanent expansion must be recorded and 
included in the inspector's report.
    (j) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test as follows:
    (1) The test must be by water-jacket, operated so as to obtain 
accurate data. The pressure gauge must permit reading to an accuracy of 
1 percent. The expansion gauge must permit reading of total expansion to 
an accuracy either of 1 percent or 0.1 cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. If, due to failure of 
the test apparatus, the test pressure cannot be maintained, the test may 
be repeated at a pressure increased by 10 percent or 100 psig, whichever 
is the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Each container must be tested to at least 2 times service 
pressure.
    (5) Container must then be inspected. Any wall thickness lower than 
that required by paragraph (f) of this section must be cause for 
rejection. Bulges and cracks must be cause for rejection. Welded joint 
defects exceeding requirements of paragraph (k) of this section must be 
cause for rejection.
    (k) Radiographic inspection. Radiographic inspection is required on 
all welded joints which are subjected to internal pressure, except that 
at the discretion of the disinterested inspector, openings less than 25 
percent of the container diameter need not be subjected to radiographic 
inspection. Evidence of any defects likely to seriously weaken the 
container is cause for rejection. Radiographic inspection must be 
performed subsequent to the hydrostatic test.
    (l) Burst test. One container taken at random out of 200 or less 
must be hydrostatically tested to destruction. Rupture pressure must be 
included as part of the inspector's report.
    (m) Flattening test. A flattening test must be performed as follows:
    (1) For spheres the test must be at the weld between parallel steel 
plates

[[Page 43]]

on a press with welded seam at right angles to the plates. Test one 
sphere taken at random out of each lot of 200 or less after the 
hydrostatic test. Any projecting appurtenances may be cut off (by 
mechanical means only) prior to crushing.
    (2) For cylinders the test must be between knife edges, wedge 
shaped, 60[deg] angle, rounded to \1/2\-inch radius. Test one cylinder 
taken at random out of each lot of 200 or less, after the hydrostatic 
test.
    (n) Acceptable results for flattening and burst tests. Acceptable 
results for flattening and burst tests are as follows:
    (1) Flattening required to 50 percent of the original outside 
diameter without cracking.
    (2) Burst pressure must be at least 3 times the service pressure.
    (o) Rejected containers. Repair of welded seams by welding prior to 
process treatment is authorized. Subsequent thereto, containers must be 
heat treated and pass all prescribed tests.
    (p) Duties of inspector. In addition to the requirements of Sec. 
178.35, the inspector must verify that all tests are conducted at 
temperatures between 60 [deg]F and 90 [deg]F.
    (q) Marking. Markings must be stamped plainly and permanently on a 
permanent attachment or on a metal nameplate permanently secured to the 
container by means other than soft solder.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, 
45388, Aug. 28, 2001; 67 FR 51653, Aug. 8, 2002; 68 FR 75748, Dec. 31, 
2003]



Sec. 178.50  Specification 4B welded or brazed steel cylinders.

    (a) Type, size, and service pressure. A DOT 4B is a welded or brazed 
steel cylinder with longitudinal seams that are forged lap-welded or 
brazed and with water capacity (nominal) not over 1,000 pounds and a 
service pressure of at least 150 but not over 500 psig. Cylinders closed 
in by spinning process are not authorized.
    (b) Steel. Open-hearth, electric or basic oxygen process steel of 
uniform quality must be used. Content percent may not exceed the 
following: Carbon, 0.25; phosphorus, 0.045; sulphur, 0.050.
    (c) Identification of material. Material must be identified by any 
suitable method except that plates and billets for hotdrawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. Exposed bottom welds on cylinders 
over 18 inches long must be protected by footrings. Welding procedures 
and operators must be qualified in accordance with CGA Pamphlet C-3 
(IBR, see Sec. 171.7 of this subchapter). Seams must be made as 
follows:
    (1) Welded or brazed circumferential seams. Heads attached by 
brazing must have a driving fit with the shell, unless the shell is 
crimped, swedged, or curled over the skirt or flange of the head, and be 
thoroughly brazed until complete penetration by the brazing material of 
the brazed joint is secured. Depth of brazing from end of shell must be 
at least four times the thickness of shell metal.
    (2) Longitudinal seams in shells. Longitudinal seams must be forged 
lap welded, by copper brazing, by copper alloy brazing, or by silver 
alloy brazing. Copper alloy composition must be: Copper, 95 percent 
minimum; Silicon, 1.5 percent to 3.85 percent; Manganese, 0.25 percent 
to 1.10 percent. The melting point of the silver alloy brazing material 
must be in excess of 1000 [deg]F. When brazed, the plate edge must be 
lapped at least eight times the thickness of plate, laps being held in 
position, substantially metal to metal, by riveting or electric spot-
welding; brazing must be done by using a suitable flux and by placing 
brazing material on one side of seam and applying heat until this 
material shows uniformly along the seam of the other side.
    (e) Welding or brazing. Only the attachment of neckrings, footrings, 
handles, bosses, pads, and valve protection rings to the tops and 
bottoms of cylinders by welding or brazing is authorized. Such 
attachments and the portion

[[Page 44]]

of the container to which they are attached must be made of weldable 
steel, the carbon content of which may not exceed 0.25 percent except in 
the case of 4130X steel which may be used with proper welding procedure.
    (f) Wall thickness. The wall thickness of the cylinder must comply 
with the following requirements:
    (1) For cylinders with outside diameters over 6 inches the minimum 
wall thickness must be 0.090 inch. In any case, the minimum wall 
thickness must be such that calculated wall stress at minimum test 
pressure (paragraph (i)(4) of this section) may not exceed the following 
values:
    (i) 24,000 psi for cylinders without longitudinal seam.
    (ii) 22,800 psig for cylinders having copper brazed or silver alloy 
brazed longitudinal seam.
    (iii) 18,000 psi for cylinders having forged lapped welded 
longitudinal seam.
    (2) Calculation must be made by the formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test or 450 psig 
          whichever is the greater;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. Cylinder body and heads, formed by drawing or 
pressing, must be uniformly and properly heat treated prior to tests.
    (h) Opening in cylinders. Openings in cylinders must conform to the 
following:
    (1) Each opening in cylinders, except those for safety devices, must 
be provided with a fitting, boss, or pad, securely attached to cylinder 
by brazing or by welding or by threads. Fitting, boss, or pad must be of 
steel suitable for the method of attachment employed, and which need not 
be identified or verified as to analysis except that if attachment is by 
welding, carbon content may not exceed 0.25 percent. If threads are 
used, they must comply with the following:
    (i) Threads must be clean cut, even without checks, and tapped to 
gauge.
    (ii) Taper threads to be of length not less than as specified for 
American Standard taper pipe threads.
    (iii) Straight threads, having at least 4 engaged threads, to have 
tight fit and calculated shear strength at least 10 times the test 
pressure of the cylinder; gaskets required, adequate to prevent leakage.
    (iv) A brass fitting may be brazed to the steel boss or flange on 
cylinders used as component parts of hand fire extinguishers.
    (2) The closure of a fitting, boss, or pad must be adequate to 
prevent leakage.
    (i) Hydrostatic test. Cylinders must withstand a hydrostatic test as 
follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy either of 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Cylinders must be tested as follows:
    (i) At least one cylinder selected at random out of each lot of 200 
or less must be tested as outlined in paragraphs (i)(1), (i)(2), and 
(i)(3) of this section to at least two times service pressure.
    (ii) All cylinders not tested as outlined in paragraph (i)(4)(i) of 
this section must be examined under pressure of at least two times 
service pressure and show no defect.
    (j) Flattening test. After the hydrostatic test, a flattening test 
must be performed on one cylinder taken at random out or each lot of 200 
or less, by placing the cylinder between wedge

[[Page 45]]

shaped knife edges having a 60[deg] included angle, rounded to \1/2\-
inch radius. The longitudinal axis of the cylinder must be at a 90-
degree angle to knife edges during the test. For lots of 30 or less, 
flattening tests are authorized to be made on a ring at least 8 inches 
long cut from each cylinder and subjected to same heat treatment as the 
finished cylinder.
    (k) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material as follows:
    (1) The test is required on 2 specimens cut from 1 cylinder, or part 
thereof heat-treated as required, taken at random out of each lot of 200 
or less. For lots of 30 or less, physical tests are authorized to be 
made on a ring at least 8 inches long cut from each cylinder and 
subjected to same heat treatment as the finished cylinder.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width of not over 1\1/2\ 
inches, a gauge length of 2 inches with a width of not over 1\1/2\ 
inches, or a gauge length at least 24 times the thickness with a width 
not over 6 times the thickness is authorized when a cylinder wall is not 
over \3/16\ inch thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within one inch of each end of the reduced 
section.
    (iii) When size of cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold, by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi, and strain 
indicator reading must be set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (l) Acceptable results for physical and flattening tests. Either of 
the following is an acceptable result:
    (1) An elongation of at least 40 percent for a 2-inch gauge length 
or at least 20 percent in other cases and yield strength not over 73 
percent of tensile strength. In this instance, a flattening test is not 
required.
    (2) When cylinders are constructed of lap welded pipe, flattening 
test is required, without cracking, to 6 times the wall thickness. In 
such case, the rings (crop ends) cut from each end of pipe, must be 
tested with the weld 45[deg] or less from the point of greatest stress. 
If a ring fails, another from the same end of pipe may be tested.
    (m) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinder. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair of brazed seams by brazing and welded seams by 
welding is authorized.
    (n) Markings. Markings must be stamped plainly and permanently in 
any of the following locations on the cylinder:
    (1) On shoulders and top heads when they are not less than 0.087-
inch thick.

[[Page 46]]

    (2) On side wall adjacent to top head for side walls which are not 
less than 0.090 inch thick.
    (3) On a cylindrical portion of the shell which extends beyond the 
recessed bottom of the cylinder, constituting an integral and non-
pressure part of the cylinder.
    (4) On a metal plate attached to the top of the cylinder or 
permanent part thereof; sufficient space must be left on the plate to 
provide for stamping at least six retest dates; the plate must be at 
least \1/16\-inch thick and must be attached by welding, or by brazing. 
The brazing rod must melt at a temperature of 1100 [deg]F. Welding or 
brazing must be along all the edges of the plate.
    (5) On the neck, neckring, valve boss, valve protection sleeve, or 
similar part permanently attached to the top of the cylinder.
    (6) On the footring permanently attached to the cylinder, provided 
the water capacity of the cylinder does not exceed 25 pounds.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 62 FR 51561, 
Oct. 1, 1997; 66 FR 45385, 45388, Aug. 28, 2001; 67 FR 51653, Aug. 8, 
2002; 68 FR 75748, Dec. 31, 2003]



Sec. 178.51  Specification 4BA welded or brazed steel cylinders.

    (a) Type, size, and service pressure. A DOT 4BA cylinder is a 
cylinder, either spherical or cylindrical in shape, with a water 
capacity of 1,000 pounds or less and a service pressure of at least 225 
and not over 500 psig. Closures made by the spinning process are not 
authorized.
    (1) Spherical type cylinders must be made from two seamless 
hemispheres joined by the welding of one circumferential seam.
    (2) Cylindrical type cylinders must be of circumferentially welded 
or brazed construction.
    (b) Steel. The steel used in the construction of the cylinder must 
be as specified in table 1 of appendix A to this part.
    (c) Identification of material. Material must be identified by any 
suitable method except that plates and billets for hotdrawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. Exposed bottom welds on cylinders 
over 18 inches long must be protected by footrings.
    (1) Seams must be made as follows:
    (i) Minimum thickness of heads and bottoms must be not less than 90 
percent of the required thickness of the side wall.
    (ii) Circumferential seams must be made by welding or by brazing. 
Heads must be attached by brazing and must have a driving fit with the 
shell, unless the shell is crimped, swedged or curled over the skirt or 
flange of the head and must be thoroughly brazed until complete 
penetration by the brazing material of the brazed joint is secured. 
Depth of brazing from end of the shell must be at least four times the 
thickness of shell metal.
    (iii) Longitudinal seams in shells must be made by copper brazing, 
copper alloy brazing, or by silver alloy brazing. Copper alloy 
composition must be: Copper 95 percent minimum, Silicon 1.5 percent to 
3.85 percent, Manganese 0.25 percent to 1.10 percent. The melting point 
of the silver alloy brazing material must be in excess of 1,000 [deg]F. 
The plate edge must be lapped at least eight times the thickness of 
plate, laps being held in position, substantially metal to metal, by 
riveting or by electric spot-welding. Brazing must be done by using a 
suitable flux and by placing brazing material on one side of seam and 
applying heat until this material shows uniformly along the seam of the 
other side. Strength of longitudinal seam: Copper brazed longitudinal 
seam must have strength at least \3/2\ times the strength of the steel 
wall.
    (2) Welding procedures and operators must be qualified in accordance 
with CGA Pamphlet C-3 (IBR, see Sec. 171.7 of this subchapter).
    (e) Welding and brazing. Only the welding or brazing of neckrings, 
footrings, handles, bosses, pads, and valve protection rings to the tops 
and

[[Page 47]]

bottoms of cylinders is authorized. Provided that such attachments and 
the portion of the container to which they are attached are made of 
weldable steel, the carbon content of which may not exceed 0.25 percent 
except in the case of 4130x steel which may be used with proper welding 
procedure.
    (f) Wall thickness. The minimum wall thickness of the cylinder must 
meet the following conditions:
    (1) For any cylinder with an outside diameter of greater than 6 
inches, the minimum wall thickness is 0.078 inch. In any case the 
minimum wall thickness must be such that the calculated wall stress at 
the minimum test pressure may not exceed the lesser value of any of the 
following:
    (i) The value shown in table 1 of appendix A to this part, for the 
particular material under consideration;
    (ii) One-half of the minimum tensile strength of the material 
determined as required in paragraph (j) of this section;
    (iii) 35,000 psi; or
    (iv) Further provided that wall stress for cylinders having copper 
brazed longitudinal seams may not exceed 95 percent of any of the above 
values. Measured wall thickness may not include galvanizing or other 
protective coating.
    (2) Cylinders that are cylindrical in shape must have the wall 
stress calculated by the formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test;
D = outside diameter in inches;
d = inside diameter in inches.

    (3) Cylinders that are spherical in shape must have the wall stress 
calculated by the formula:

S = PD / 4tE

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test;
D = outside diameter in inches;
t = minimum wall thickness in inches;
E = 0.85 (provides 85 percent weld efficiency factor which must be 
          applied in the girth weld area and heat affected zones which 
          zone must extend a distance of 6 times wall thickness from 
          center line of weld);
E = 1.0 (for all other areas).

    (4) For a cylinder with a wall thickness less than 0.100 inch, the 
ratio of tangential length to outside diameter may not exceed 4.1.
    (g) Heat treatment. Cylinders must be heat treated in accordance 
with the following requirements:
    (1) Each cylinder must be uniformly and properly heat treated prior 
to test by the applicable method shown in table 1 of appendix A to this 
part. Heat treatment must be accomplished after all forming and welding 
operations, except that when brazed joints are used, heat treatment must 
follow any forming and welding operations, but may be done before, 
during or after the brazing operations.
    (2) Heat treatment is not required after the welding or brazing of 
weldable low carbon parts to attachments of similar material which have 
been previously welded or brazed to the top or bottom of cylinders and 
properly heat treated, provided such subsequent welding or brazing does 
not produce a temperature in excess of 400 [deg]F in any part of the top 
or bottom material.
    (h) Openings in cylinders. Openings in cylinders must comply with 
the following requirements:
    (1) Any opening must be placed on other than a cylindrical surface.
    (2) Each opening in a spherical type cylinder must be provided with 
a fitting, boss, or pad of weldable steel securely attached to the 
container by fusion welding.
    (3) Each opening in a cylindrical type cylinder must be provided 
with a fitting, boss, or pad, securely attached to container by brazing 
or by welding.
    (4) If threads are used, they must comply with the following:
    (i) Threads must be clean-cut, even, without checks and tapped to 
gauge.
    (ii) Taper threads must be of a length not less than that specified 
for American Standard taper pipe threads.
    (iii) Straight threads, having at least 4 engaged threads, must have 
a tight fit and a calculated shear strength of at least 10 times the 
test pressure of the cylinder. Gaskets, adequate to prevent leakage, are 
required.

[[Page 48]]

    (i) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test, as follows:
    (1) The test must be by water jacket, or other suitable method, 
operated so as to obtain accurate data. A pressure gauge must permit 
reading to an accuracy of 1 percent. An expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat treatment and previous to the official test may not 
exceed 90 percent of the test pressure.
    (3) Permanent volumetric expansion may not exceed 10 percent of the 
total volumetric expansion at test pressure.
    (4) Cylinders must be tested as follows:
    (i) At least one cylinder selected at random out of each lot of 200 
or less must be tested as outlined in paragraphs (i)(1), (i)(2), and 
(i)(3) of this section to at least two times service pressure.
    (ii) All cylinders not tested as outlined in paragraph (i)(4)(i) of 
this section must be examined under pressure of at least two times 
service pressure and show no defect.
    (j) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material, as follows:
    (1) The test is required on 2 specimens cut from one cylinder or 
part thereof having passed the hydrostatic test and heat-treated as 
required, taken at random out of each lot of 200 or less. Physical tests 
for spheres are required on 2 specimens cut from flat representative 
sample plates of the same heat taken at random from the steel used to 
produce the spheres. This flat steel from which 2 specimens are to be 
cut must receive the same heat treatment as the spheres themselves. 
Sample plates must be taken from each lot of 200 or less spheres.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
or a gauge length of 2 inches with a width not over 1\1/2\ inches, or a 
gauge length at least 24 times the thickness with a width not over 6 
times the thickness is authorized when a cylinder wall is not over \3/
16\ inch thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within one inch of each end of the reduced 
section.
    (iii) When size of the cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold, by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load''), corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain 
reference must be set while the specimen is under a stress of 12,000 
psi, and the strain indicator reading must be set at the calculated 
corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.

[[Page 49]]

    (k) Elongation. Physical test specimens must show at least a 40 
percent elongation for a 2-inch gauge length or at least 20 percent in 
other cases. Except that these elongation percentages may be reduced 
numerically by 2 for 2-inch specimens, and by 1 in other cases, for each 
7,500 psi increment of tensile strength above 50,000 psi to a maximum of 
four such increments.
    (l) Tests of welds. Except for brazed seams, welds must be tested as 
follows:
    (1) Tensile test. A specimen must be cut from one cylinder of each 
lot of 200 or less, or welded test plate. The welded test plate must be 
of one of the heats in the lot of 200 or less which it represents, in 
the same condition and approximately the same thickness as the cylinder 
wall except that in no case must it be of a lesser thickness than that 
required for a quarter size Charpy impact specimen. The weld must be 
made by the same procedures and subjected to the same heat treatment as 
the major weld on the cylinder. The specimen must be taken from across 
the major seam and must be prepared and tested in accordance with and 
must meet the requirements of CGA Pamphlet C-3 (IBR, see Sec. 171.7 of 
this subchapter). Should this specimen fail to meet the requirements, 
specimens may be taken from two additional cylinders or welded test 
plates from the same lot and tested. If either of the latter specimens 
fail to meet the requirements, the entire lot represented must be 
rejected.
    (2) Guided bend test. A root bend test specimen must be cut from the 
cylinder or welded test plate, used for the tensile test specified in 
paragraph (l)(1) of this section. Specimens must be taken from across 
the major seam and must be prepared and tested in accordance with and 
must meet the requirements of CGA Pamphlet C-3.
    (3) Alternate guided-bend test. This test may be used and must be as 
required by CGA Pamphlet C-3. The specimen must be bent until the 
elongation at the outer surface, adjacent to the root of the weld, 
between the lightly scribed gage lines a to b, must be at least 20 
percent, except that this percentage may be reduced for steels having a 
tensile strength in excess of 50,000 psig, as provided in paragraph (k) 
of this section.
    (m) Rejected cylinders. Reheat treatment is authorized for rejected 
cylinders. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair of brazed seams by brazing and welded seams by 
welding is authorized.
    (n) Markings. Markings must be stamped plainly and permanently in 
one of the following locations on the cylinder:
    (1) On shoulders and top heads not less than 0.087 inch thick.
    (2) On side wall adjacent to top head for side walls not less than 
0.090 inch thick.
    (3) On a cylindrical portion of the shell which extends beyond the 
recessed bottom of the cylinder constituting an integral and non-
pressure part of the cylinder.
    (4) On a plate attached to the top of the cylinder or permanent part 
thereof; sufficient space must be left on the plate to provide for 
stamping at least six retest dates; the plate must be at least \1/16\ 
inch thick and must be attached by welding, or by brazing at a 
temperature of at least 1100 [deg]F., throughout all edges of the plate.
    (5) On the neck, neckring, valve boss, valve protection sleeve, or 
similar part permanently attached to the top of the cylinder.
    (6) On the footring permanently attached to the cylinder, provided 
the water capacity of the cylinder does not exceed 25 pounds.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 4535, 
Aug. 28, 2001; 67 FR 16015, Sept. 27, 2002; 67 FR 51653, Aug. 8, 2002; 
68 FR 75748, Dec. 31, 2003]



Sec. 178.53  Specification 4D welded steel cylinders for aircraft use.

    (a) Type, size, and service pressure. A DOT 4D cylinder is a welded 
steel sphere (two seamless hemispheres) or circumferentially welded 
cylinder (two seamless drawn shells) with a water capacity not over 100 
pounds and a service pressure of at least 300 but not over 500 psig. 
Cylinders closed in by spinning process are not authorized.
    (b) Steel. Open-hearth or electric steel of uniform and weldable 
quality must be used. Content may not exceed the

[[Page 50]]

following: Carbon, 0.25; phosphorus, 0.045; sulphur, 0.050, except that 
the following steels commercially known as 4130X and Type 304, 316, 321, 
and 347 stainless steels may be used with proper welding procedure. A 
heat of steel made under table 1 in this paragraph (b), check chemical 
analysis of which is slightly out of the specified range, is acceptable, 
if satisfactory in all other respects, provided the tolerances shown in 
table 2 in this paragraph (b) are not exceeded, except as approved by 
the Associate Administrator. The following chemical analyses are 
authorized:

                          Table 1--4130X Steel
------------------------------------------------------------------------
                   4130X                               Percent
------------------------------------------------------------------------
Carbon.....................................  0.25/0.35.
Manganese..................................  0.40/0.60.
Phosphorus.................................  0.04 max.
Sulphur....................................  0.05 max
Silicon....................................  0.15/0.35.
Chromium...................................  0.80/1.10.
Molybdenum.................................  0.15/0.25.
Zirconium..................................  None.
Nickel.....................................  None.
------------------------------------------------------------------------


                                      Table 2--Authorized Stainless Steels
----------------------------------------------------------------------------------------------------------------
                                                                         Stainless steels
                                                 ---------------------------------------------------------------
                                                   304 (percent)   316 (percent)   321 (percent)   347 (percent)
----------------------------------------------------------------------------------------------------------------
Carbon (max)....................................            0.08            0.08            0.08            0.08
Manganese (max).................................            2.00            2.00            2.00            2.00
Phosphorus (max)................................            .030            .045            .030            .030
Sulphur (max)...................................            .030            .030            .030            .030
Silicon (max)...................................             .75            1.00             .75             .75
Nickel..........................................        8.0/11.0       10.0/14.0        9.0/13.0        9.0/13.0
Chromium........................................       18.0/20.0       16.0/18.0       17.0/20.0       17.0/20.0
Molybdenum......................................  ..............         2.0/3.0  ..............  ..............
Titanium........................................  ..............  ..............           (\1\)  ..............
Columbium.......................................  ..............  ..............  ..............           (\2\)
----------------------------------------------------------------------------------------------------------------
\1\ Titanium may not be less than 5C and not more than 0.60%.
\2\ Columbium may not be less than 10C and not more than 1.0%.


                                       Table 3--Check Analysis Tolerances
----------------------------------------------------------------------------------------------------------------
                                                                                        Tolerance (percent) over
                                                                                          the maximum limit or
                                                                                         under the minimum limit
            Element                       Limit or maximum specified (percent)         -------------------------
                                                                                           Under         Over
                                                                                          minimum      maximum
                                                                                           limit        limit
----------------------------------------------------------------------------------------------------------------
Carbon.........................  To 0.15 incl.........................................         0.01         0.01
                                 Over 0.15 to 0.40 incl...............................          .03          .04
Manganese......................  To 0.60 incl.........................................          .03          .03
                                 Over 1.15 to 2.50 incl...............................          .05          .05
Phosphorus \1\.................  All ranges...........................................  ...........          .01
Sulphur........................  All ranges...........................................  ...........          .01
Silicon........................  To 0.30 incl.........................................          .02          .03
                                 Over 0.30 to 1.00 incl...............................          .05          .05
Nickel.........................  Over 5.30 to 10.00 incl..............................          .10          .10
                                 Over 10.00 to 14.00 incl.............................          .15          .15
Chromium.......................  To 0.90 incl.........................................          .03          .03
                                 Over 0.90 to 2.10 incl...............................          .05          .05
                                 Over 15.00 to 20.00 incl.............................          .20          .20
Molybdenum.....................  To 0.20 incl.........................................          .01          .01
                                 Over 0.20 to 0.40 incl...............................          .02          .02
                                 Over 1.75 to 3.0 incl................................          .10          .10
Titanium.......................  All ranges...........................................          .05          .05
Columbium......................  All ranges...........................................          .05          .05
----------------------------------------------------------------------------------------------------------------
\1\ Rephosphorized steels not subject to check analysis for phosphorus.

    (c) Identification of material. Material must be identified by any 
suitable method except that plates and billets for hotdrawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is

[[Page 51]]

permitted that is likely to weaken the finished container appreciably. A 
reasonably smooth and uniform surface finish is required. Welding 
procedures and operators must be qualified in accordance with CGA 
Pamphlet C-3 (IBR, see Sec. 171.7 of this subchapter).
    (e) Wall thickness. The wall stress at the minimum test pressure may 
not exceed 24,000 psi, except where steels commercially known as 4130X, 
types 304, 316, 321, and 347 stainless steels are used, stress at the 
test pressures may not exceed 37,000 psi. The minimum wall thickness for 
any container having a capacity of 1,100 cubic inches or less is 0.04 
inch. The minimum wall thickness for any container having a capacity in 
excess of 1,100 cubic inches is 0.095 inch. Calculations must be done by 
the following:
    (1) Calculation for a ``sphere'' must be made by the formula:

S = PD / 4tE

Where:

S = wall stress in psi;
P = test pressure prescribed for water jacket test, i.e., at least two 
          times service pressure, in psig;
D = outside diameter in inches;
t = minimum wall thickness in inches;
E = 0.85 (provides 85 percent weld efficiency factor which must be 
          applied in the girth weld area and heat affected zones which 
          zone must extend a distance of 6 times wall thickness from 
          center line of weld);
E = 1.0 (for all other areas).

    (2) Calculation for a cylinder must be made by the formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\T12\)

Where:

S = wall stress in psi;
P = test pressure prescribed for water jacket test, i.e., at least two 
          times service pressure, in psig;
D = outside diameter in inches;
d = inside diameter in inches.

    (f) Heat treatment. The completed cylinders must be uniformly and 
properly heat-treated prior to tests.
    (g) Openings in container. Openings in cylinders must comply with 
the following:
    (1) Each opening in the container, except those for safety devices, 
must be provided with a fitting, boss, or pad, securely attached to the 
container by brazing or by welding or by threads. If threads are used, 
they must comply with the following:
    (i) Threads must be clean cut, even, without checks, and tapped to 
gauge.
    (ii) Taper threads must be of a length not less than that specified 
for American Standard taper pipe threads.
    (iii) Straight threads, having at least 4 engaged threads, must have 
a tight fit and calculated shear strength of at least 10 times the test 
pressure of the container. Gaskets, adequate to prevent leakage, are 
required.
    (2) Closure of a fitting, boss, or pad must be adequate to prevent 
leakage.
    (h) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test, as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. A pressure gauge must permit a 
reading to an accuracy of 1 percent. An expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of the 
total volumetric expansion at test pressure.
    (4) Containers must be tested as follows:
    (i) Each container to at least 2 times service pressure; or
    (ii) One container out of each lot of 200 or less to at least 3 
times service pressure. Others must be examined under pressure of 2 
times service pressure and show no defects.
    (i) Flattening test for spheres and cylinders. Spheres and cylinders 
must be subjected to a flattening test as follows:
    (1) One sphere taken at random out of each lot of 200 or less must 
be subjected to a flattening test as follows:
    (i) The test must be performed after the hydrostatic test.

[[Page 52]]

    (ii) The test must be between parallel steel plates on a press with 
a welded seam at right angles to the plates. Any projecting 
appurtenances may be cut off (by mechanical means only) prior to 
crushing.
    (2) One cylinder taken at random out of each lot of 200 or less must 
be subjected to a flattening test, as follows:
    (i) The test must be performed after the hydrostatic test.
    (ii) The test must be between knife edges, wedge shaped, 60[deg] 
angle, rounded to \1/2\ inch radius. For lots of 30 or less, physical 
tests are authorized to be made on a ring at least 8 inches long cut 
from each cylinder and subjected to the same heat treatment as the 
finished cylinder.
    (j) Physical test and specimens for spheres and cylinders. Spheres 
and cylinders must be subjected to a physical test as follows:
    (1) Physical test for spheres are required on 2 specimens cut from a 
flat representative sample plate of the same heat taken at random from 
the steel used to produce the sphere. This flat steel from which the 2 
specimens are to be cut must receive the same heat-treatment as the 
spheres themselves. Sample plates must be taken for each lot of 200 or 
less spheres.
    (2) Specimens for spheres must have a gauge length 2 inches with a 
width not over 1\1/2\ inches, or a gauge length at least 24 times the 
thickness with a width not over 6 times the thickness is authorized when 
a wall is not over \3/16\ inch thick.
    (3) Physical test for cylinders is required on 2 specimens cut from 
1 cylinder taken at random out of each lot of 200 or less. For lots of 
30 or less, physical tests are authorized to be made on a ring at least 
8 inches long cut from each cylinder and subjected to the same heat 
treatment as the finished cylinder.
    (4) Specimens for cylinders must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
or a gauge length of 2 inches with a width not over 1\1/2\ inches, or a 
gauge length at least 24 times the thickness with a width not over 6 
times the thickness is authorized when a cylinder wall is not over \3/
16\ inch thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within 1 inch of each end of the reduced 
section. Heating of the specimen for any purpose is not authorized.
    (5) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi and the strain 
indicator reading being set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (k) Acceptable results for physical and flattening tests. Either of 
the following is an acceptable result:
    (1) An elongation of at least 40 percent for a 2 inch gauge length 
or at least 20 percent in other cases and yield strength not over 73 
percent of tensile strength. In this instance, the flattening test is 
not required.
    (2) An elongation of at least 20 percent for a 2 inch gauge length 
or 10 percent in other cases. Flattening is required to 50 percent of 
the original outside diameter without cracking.
    (l) Rejected cylinders. Reheat-treatment is authorized for rejected 
cylinders. Subsequent thereto, containers

[[Page 53]]

must pass all prescribed tests to be acceptable. Repair of welded seams 
by welding prior to reheat-treatment is authorized.
    (m) Marking. Marking on each container by stamping plainly and 
permanently are only authorized where the metal is at least 0.09 inch 
thick, or on a metal nameplate permanently secured to the container by 
means other than soft solder, or by means that would not reduce the wall 
thickness.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, 
45388, Aug. 28, 2001; 67 FR 51653, Aug. 8, 2002; 68 FR 75748, Dec. 31, 
2003]



Sec. 178.55  Specification 4B240ET welded or brazed cylinders.

    (a) Type, spinning process, size and service pressure. A DOT 4B240ET 
cylinder is a brazed type cylinder made from electric resistance welded 
tubing. The maximum water capacity of this cylinder is 12 pounds or 333 
cubic inches and the service must be 240 psig. The maximum outside 
diameter of the shell must be five inches and maximum length of the 
shell is 21 inches. Cylinders closed in by a spinning process are 
authorized.
    (b) Steel. Open-hearth, basic oxygen, or electric steel of uniform 
quality must be used. Plain carbon steel content may not exceed the 
following: Carbon, 0.25; phosphorus, 0.045; sulfur, 0.050. The addition 
of other elements for alloying effect is prohibited.
    (c) Identification of material. Material must be identified by any 
suitable method.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. Heads may be attached to shells by 
lap brazing or may be formed integrally. The thickness of the bottom of 
cylinders welded or formed by spinning is, under no condition, to be 
less than two times the minimum wall thickness of the cylindrical shell. 
Such bottom thicknesses must be measured within an area bounded by a 
line representing the points of contact between the cylinder and the 
floor when the cylinder is in a vertical position. Seams must conform to 
the following:
    (1) Circumferential seams must be by brazing only. Heads must be 
attached to shells by the lap brazing method and must overlap not less 
than four times the wall thickness. Brazing material must have a melting 
point of not less than 1000 [deg]F. Heads must have a driving fit with 
the shell unless the shell is crimped, swedged, or curled over the skirt 
or flange of the head and be thoroughly brazed until complete 
penetration of the joint by the brazing material is secured. Brazed 
joints may be repaired by brazing.
    (2) Longitudinal seams in shell must be by electric resistance 
welded joints only. No repairs to longitudinal joints is permitted.
    (3) Welding procedures and operators must be qualified in accordance 
with CGA C-3 (IBR, see Sec. 171.7 of this subchapter).
    (e) Welding or brazing. Only the attachment, by welding or brazing, 
to the tops and bottoms of cylinders of neckrings, footrings, handles, 
bosses, pads, and valve protection rings is authorized. Provided that 
such attachments and the portion of the container to which they are 
attached are made of weldable steel, the carbon content of which may not 
exceed 0.25 percent.
    (f) Wall thickness. The wall stress must be at least two times the 
service pressure and may not exceed 18,000 psi. The minimum wall 
thickness is 0.044 inch. Calculation must be made by the following 
formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = wall stress in psig;
P = 2 times service pressure;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. Heads formed by drawing or pressing must be 
uniformly and properly heat treated prior to tests. Cylinders with 
integral formed heads or bases must be subjected to a normalizing 
operation. Normalizing and brazing operations may be combined, provided 
the operation is carried out at a temperature in excess of the upper 
critical temperature of the steel.

[[Page 54]]

    (h) Openings in cylinders. Openings in cylinders must comply with 
the following:
    (1) Each opening in cylinders, except those for safety devices, must 
be provided with a fitting, boss, or pad, securely attached to the 
cylinder by brazing or by welding or by threads. A fitting, boss, or pad 
must be of steel suitable for the method of attachment employed, and 
which need not be identified or verified as to analysis, except that if 
attachment is by welding, carbon content may not exceed 0.25 percent. If 
threads are used, they must comply with the following:
    (i) Threads must be clean cut, even without checks, and tapped to 
gauge.
    (ii) Taper threads to be of length not less than as specified for 
American Standard taper pipe threads.
    (iii) Straight threads, having at least 4 engaged threads, to have 
tight fit and calculated shear strength at least 10 times the test 
pressure of the cylinder; gaskets required, adequate to prevent leakage.
    (2) Closure of a fitting, boss, or pad must be adequate to prevent 
leakage.
    (i) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Cylinders must be tested as follows:
    (i) At least one cylinder selected at random out of each lot of 200 
or less must be tested as outlined in paragraphs (i)(1), (i)(2), and 
(i)(3) of this section to at least two times service pressure.
    (ii) All cylinders not tested as outlined in paragraph (i)(4)(i) of 
this section must be examined under pressure of at least two times 
service pressure and show no defect.
    (5) Each 1000 cylinders or less successively produced each day must 
constitute a lot. One cylinder must be selected from each lot and 
hydrostatically tested to destruction. If this cylinder bursts below 
five times the service pressure, then two additional cylinders must be 
selected and subjected to this test. If either of these cylinders fails 
by bursting below five times the service pressure then the entire lot 
must be rejected. All cylinders constituting a lot must be of identical 
size, construction heat-treatment, finish, and quality.
    (j) Flattening test. Following the hydrostatic test, one cylinder 
taken at random out of each lot of 200 or less, must be subjected to a 
flattening test that is between knife edges, wedge shaped, 60[deg] 
angle, rounded to \1/2\ inch radius.
    (k) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material, as follows:
    (1) The test is required on 2 specimens cut from 1 cylinder, or part 
thereof heat-treated as required, taken at random out of each lot of 200 
or less in the case of cylinders of capacity greater than 86 cubic 
inches and out of each lot of 500 or less for cylinders having a 
capacity of 86 cubic inches or less.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
a gauge length of 2 inches with a width not over 1\1/2\ inches, or a 
gauge length at least 24 times the thickness with a width not over 6 
times the thickness is authorized when a cylinder wall is not over \3/
16\ inch thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within one inch of each end of the reduced 
section.

[[Page 55]]

    (iii) When size of cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi and the strain 
indicator reading being set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (l) Acceptable results for physical and flattening tests. Acceptable 
results for the physical and flattening tests are an elongation of at 
least 40 percent for a 2 inch gauge length or at least 20 percent in 
other cases and a yield strength not over 73 percent of tensile 
strength. In this instance the flattening test is required, without 
cracking, to six times the wall thickness with a weld 90[deg] from the 
direction of the applied load. Two rings cut from the ends of length of 
pipe used in production of a lot may be used for the flattening test 
provided the rings accompany the lot which they represent in all thermal 
processing operations. At least one of the rings must pass the 
flattening test.
    (m) Leakage test. All spun cylinders and plugged cylinders must be 
tested for leakage by gas or air pressure after the bottom has been 
cleaned and is free from all moisture, subject to the following 
conditions:
    (1) Pressure, approximately the same as but no less than service 
pressure, must be applied to one side of the finished bottom over an 
area of at least \1/16\ of the total area of the bottom but not less 
than \3/4\ inch in diameter, including the closure, for at least 1 
minute, during which time the other side of the bottom exposed to 
pressure must be covered with water and closely examined for indications 
of leakage. Except as provided in paragraph (n) of this section, 
cylinders which are leaking must be rejected.
    (2) A spun cylinder is one in which an end closure in the finished 
cylinder has been welded by the spinning process.
    (3) A plugged cylinder is one in which a permanent closure in the 
bottom of a finished cylinder has been effected by a plug.
    (4) As a safety precaution, if the manufacturer elects to make this 
test before the hydrostatic test, he should design his apparatus so that 
the pressure is applied to the smallest area practicable, around the 
point of closure, and so as to use the smallest possible volume of air 
or gas.
    (n) Rejected cylinders. Repairs of rejected cylinders is authorized. 
Cylinders that are leaking must be rejected, except that:
    (1) Spun cylinders rejected under the provisions of paragraph (m) of 
this section may be removed from the spun cylinder category by drilling 
to remove defective material, tapping, and plugging.
    (2) Brazed joints may be rebrazed.
    (3) Subsequent to the operations noted in paragraphs (n)(1) and 
(n)(2) of this section, acceptable cylinders must pass all prescribed 
tests.

[[Page 56]]

    (o) Marking. Markings on each cylinder must be by stamping plainly 
and permanently on shoulder, top head, neck or valve protection collar 
which is permanently attached to the cylinders and forming an integral 
part thereof, provided that cylinders not less than 0.090 inch thick may 
be stamped on the side wall adjacent to top head.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, 
Aug. 28, 2001; 67 FR 51653, Aug. 8, 2002; 68 FR 75748, 75749, Dec. 31, 
2003]



Sec. 178.56  Specification 4AA480 welded steel cylinders.

    (a) Type, size, and service pressure. A DOT 4AA480 cylinder is a 
welded steel cylinder having a water capacity (nominal) not over 1,000 
pounds water capacity and a service pressure of 480 psig. Closures 
welded by spinning process not permitted.
    (b) Steel. The limiting chemical composition of steel authorized by 
this specification must be as shown in table I of appendix A to this 
part.
    (c) Identification of material. Material must be identified by any 
suitable method except that plates and billets for hotdrawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. Exposed bottom welds on cylinders 
over 18 inches long must be protected by footrings. Minimum thickness of 
heads and bottoms may not be less than 90 percent of the required 
thickness of the side wall. Seams must be made as follows:
    (1) Circumferential seams must be welded. Brazing is not authorized.
    (2) Longitudinal seams are not permitted.
    (3) Welding procedures and operators must be qualified in accordance 
with CGA C-3 (IBR, see Sec. 171.7 of this subchapter).
    (e) Welding. Only the welding of neckrings, footrings, bosses, pads, 
and valve protection rings to the tops and bottoms of cylinders is 
authorized. Provided that such attachments are made of weldable steel, 
the carbon content of which does not exceed 0.25 percent.
    (f) Wall thickness. The wall thickness of the cylinder must conform 
to the following:
    (1) For cylinders with an outside diameter over 5 inches, the 
minimum wall thickness is 0.078 inch. In any case, the minimum wall 
thickness must be such that the calculated wall stress at the minimum 
test pressure (in paragraph (i) of this section) may not exceed the 
lesser value of either of the following:
    (i) One-half of the minimum tensile strength of the material 
determined as required in paragraph (j) of this section; or
    (ii) 35,000 psi.
    (2) Calculation must be made by the formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test;
D = outside diameter in inches;
d = inside diameter in inches.

    (3) The ratio of tangential length to outside diameter may not 
exceed 4.0 for cylinders with a wall thickness less than 0.100 inch.
    (g) Heat treatment. Each cylinder must be uniformly and properly 
heat treated prior to tests. Any suitable heat treatment in excess of 
1100 [deg]F is authorized except that liquid quenching is not permitted. 
Heat treatment must be accomplished after all forming and welding 
operations. Heat treatment is not required after welding weldable low 
carbon parts to attachments of similar material which have been 
previously welded to the top or bottom of cylinders and properly heat 
treated, provided such subsequent welding does not produce a temperature 
in excess of 400 [deg]F., in any part of the top or bottom material.
    (h) Openings in cylinders. Openings in cylinders must conform to the 
following:
    (1) All openings must be in the heads or bases.

[[Page 57]]

    (2) Each opening in the cylinder, except those for safety devices, 
must be provided with a fitting boss, or pad, securely attached to the 
cylinder by welding or by threads. If threads are used they must comply 
with the following:
    (i) Threads must be clean-cut, even without checks and cut to gauge.
    (ii) Taper threads to be of length not less than as specified for 
American Standard taper pipe threads.
    (iii) Straight threads having at least 6 engaged threads, must have 
a tight fit and a calculated shear strength at least 10 times the test 
pressure of the cylinder. Gaskets, adequate to prevent leakage, are 
required.
    (3) Closure of a fitting, boss or pad must be adequate to prevent 
leakage.
    (i) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test as follows:
    (1) The test must be by water jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds or 
sufficiently longer to assure complete expansion. Any internal pressure 
applied after heat-treatment and before the official test may not exceed 
90 percent of the test pressure. If, due to failure of test apparatus, 
the test pressure cannot be maintained, the test may be repeated at a 
pressure increased by 10 percent or 100 psig, whichever is lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of the 
total volumetric expansion at test pressure.
    (4) Cylinders must be tested as follows:
    (i) At least one cylinder selected at random out of each lot of 200 
or less must be tested as described in paragraphs (i)(1), (i)(2), and 
(i)(3) of this section, to at least two times service pressure. If a 
selected cylinder fails, then two additional specimens must be selected 
at random from the same lot and subjected to the prescribed test. If 
either of these fails the test, then each cylinder in that lot must be 
so tested; and
    (ii) Each cylinder not tested as prescribed in paragraph (i)(4)(i) 
of this section must be examined under pressure of at least two times 
service pressure and must show no defect. A cylinder showing a defect 
must be rejected unless it may be requalified under paragraph (m) of 
this section.
    (j) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material, as follows:
    (1) The test is required on 2 specimens cut from one cylinder having 
passed the hydrostatic test, or part thereof heat-treated as required, 
taken at random out of each lot of 200 or less.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
a gauge length of 2 inches with a width not over 1\1/2\ inches, or a 
gauge length at least 24 times the thickness with a width not over 6 
times thickness is authorized when the cylinder wall is not over \3/16\ 
inch thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within one inch of each end of the reduced 
section.
    (iii) When size of cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold, by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load''), corresponding to

[[Page 58]]

the stress at which the 0.2 percent permanent strain occurs may be 
determined with sufficient accuracy by calculating the elastic extension 
of the gauge length under appropriate load and adding thereto 0.2 
percent of the gauge length. Elastic extension calculations must be 
based on an elastic modulus of 30,000,000. In the event of controversy, 
the entire stress-strain diagram must be plotted and the yield strength 
determined from the 0.2 percent offset.
    (iii) For the purpose of strain measurement, the initial strain 
reference must be set while the specimen is under a stress of 12,000 psi 
and the strain indicator reading being set at the calculated 
corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (k) Elongation. Physical test specimens must show at least a 40 
percent elongation for 2-inch gauge lengths or at least a 20 percent 
elongation in other cases. Except that these elongation percentages may 
be reduced numerically by 2 for 2-inch specimens and by 1 in other cases 
for each 7,500 psi increment of tensile strength above 50,000 psi to a 
maximum of four such increments.
    (l) Tests of welds. Welds must be tested as follows:
    (1) Tensile test. A specimen must be cut from one cylinder of each 
lot of 200 or less, or a welded test plate. The welded test plate must 
be of one of the heats in the lot of 200 or less which it represents, in 
the same condition and approximately the same thickness as the cylinder 
wall except that it may not be of a lesser thickness than that required 
for a quarter size Charpy impact specimen. The weld must be made by the 
same procedures and subjected to the same heat treatment as the major 
weld on the cylinder. The specimens must be taken across the major seam 
and must be prepared and tested in accordance with and must meet the 
requirements of CGA Pamphlet C-3. Should this specimen fail to meet the 
requirements, specimens may be taken from two additional cylinders or 
welded test plates from the same lot and tested. If either of the latter 
specimens fail to meet the requirements, the entire lot represented must 
be rejected.
    (2) Guided bend test. A root bend test specimen must be cut from the 
cylinder or a welded test plate, used for the tensile test specified in 
paragraph (l)(1) of this section. Specimens must be taken from across 
the major seam and must be prepared and tested in accordance with and 
must meet the requirements of CGA Pamphlet C-3.
    (3) Alternate guided-bend test. This test may be used and must be as 
required by CGA Pamphlet C-3. The specimen must be bent until the 
elongation at the outer surface, adjacent to the root of the weld, 
between the lightly scribed gage lines-a to b, is at least 20 percent, 
except that this percentage may be reduced for steels having a tensile 
strength in excess of 50,000 psi, as provided in paragraph (k) of this 
section.
    (m) Rejected cylinders. Reheat treatment of rejected cylinders is 
authorized. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair of welded seams by welding is authorized.
    (n) Markings. Markings must be stamped plainly and permanently in 
one of the following locations on the cylinder:
    (1) On shoulders and top heads not less than 0.087 inch thick.
    (2) On neck, valve boss, valve protection sleeve, or similar part 
permanently attached to top end of cylinder.
    (3) On a plate attached to the top of the cylinder or permanent part 
thereof: sufficient space must be left on the plate to provide for 
stamping at least six retest dates: the plate must be at least \1/16\ 
inch thick and must be attached by welding or by brazing at a 
temperature of at least 1100 [deg]F, throughout all edges of the plate.
    (4) Variations in location of markings authorized only when 
necessitated by lack of space.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, 
Aug. 28, 2001; 67 FR 51653, Aug. 8, 2002; 68 FR 75748, 75749, Dec. 31, 
2003]

[[Page 59]]



Sec. 178.57  Specification 4L welded insulated cylinders.

    (a) Type, size, service pressure, and design service temperature. A 
DOT 4L cylinder is a fusion welded insulated cylinder with a water 
capacity (nominal) not over 1,000 pounds water capacity and a service 
pressure of at least 40 but not greater than 500 psig conforming to the 
following requirements:
    (1) For liquefied hydrogen service, the cylinders must be designed 
to stand on end, with the axis of the cylindrical portion vertical.
    (2) The design service temperature is the coldest temperature for 
which a cylinder is suitable. The required design service temperatures 
for each cryogenic liquid is as follows:

------------------------------------------------------------------------
             Cryogenic liquid                Design service temperature
------------------------------------------------------------------------
Argon.....................................  Minus 320 [deg]F or colder.
Helium....................................  Minus 452 [deg]F or colder.
Hydrogen..................................  Minus 42 3 [deg]F or colder.
Neon......................................  Minus 411 [deg]F or colder.
Nitrogen..................................  Minus 320 [deg]F or colder.
Oxygen....................................  Minus 320 [deg]F or colder.
------------------------------------------------------------------------

    (b) Material. Material use in the construction of this specification 
must conform to the following:
    (1) Inner containment vessel (cylinder). Designations and limiting 
chemical compositions of steel authorized by this specification must be 
as shown in table 1 in paragraph (o) of this section.
    (2) Outer jacket. Steel or aluminum may be used subject to the 
requirements of paragraph (o)(2) of this section.
    (c) Identification of material. Material must be identified by any 
suitable method.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart and to the following requirements:
    (1) No defect is permitted that is likely to weaken the finished 
cylinder appreciably. A reasonably smooth and uniform surface finish is 
required. The shell portion must be a reasonably true cylinder.
    (2) The heads must be seamless, concave side to the pressure, 
hemispherical or ellipsoidal in shape with the major diameter not more 
than twice the minor diameter. Minimum thickness of heads may not be 
less than 90 percent of the required thickness of the sidewall. The 
heads must be reasonably true to shape, have no abrupt shape changes, 
and the skirts must be reasonably true to round.
    (3) The surface of the cylinder must be insulated. The insulating 
material must be fire resistant. The insulation on non-evacuated jackets 
must be covered with a steel jacket not less than 0.060-inch thick or an 
aluminum jacket not less than 0.070 inch thick, so constructed that 
moisture cannot come in contact with the insulating material. If a 
vacuum is maintained in the insulation space, the evacuated jacket must 
be designed for a minimum collapsing pressure of 30 psig differential 
whether made of steel or aluminum. The construction must be such that 
the total heat transfer, from the atmosphere at ambient temperature to 
the contents of the cylinder, will not exceed 0.0005 Btu per hour, per 
Fahrenheit degree differential in temperature, per pound of water 
capacity of the cylinder. For hydrogen, cryogenic liquid service, the 
total heat transfer, with a temperature differential of 520 Fahrenheit 
degrees, may not exceed that required to vent 30 SCF of hydrogen gas per 
hour.
    (4) For a cylinder having a design service temperature colder than 
minus 320 [deg]F, a calculation of the maximum weight of contents must 
be made and that weight must be marked on the cylinder as prescribed in 
Sec. 178.35.
    (5) Welding procedures and operations must be qualified in 
accordance with CGA Pamphlet C-3 (IBR, see Sec. 171.7 of this 
subchapter). In addition, an impact test of the weld must be performed 
in accordance with paragraph (l) of this section as part of the 
qualification of each welding procedure and operator.
    (e) Welding. Welding of the cylinder must be as follows:
    (1) All seams of the cylinder must be fusion welded. A means must be 
provided for accomplishing complete penetration of the joint. Only butt 
or joggle butt joints for the cylinder seams are authorized. All joints 
in the cylinder must have reasonably true alignment.
    (2) All attachments to the sidewalls and heads of the cylinder must 
be by fusion welding and must be of a

[[Page 60]]

weldable material complying with the impact requirements of paragraph 
(l) of this section.
    (3) For welding the cylinder, each procedure and operator must be 
qualified in accordance with the sections of CGA Pamphlet C-3 that 
apply. In addition, impact tests of the weld must be performed in 
accordance with paragraph (l) of this section as part of the 
qualification of each welding procedure and operator.
    (4) Brazing, soldering and threading are permitted only for joints 
not made directly to the cylinder body. Threads must comply with the 
requirements of paragraph (h) of this section.
    (f) Wall thickness. The minimum wall thickness of the cylinder must 
be such that the calculated wall stress at the minimum required test 
pressure may not exceed the least value of the following:
    (1) 45,000 psi.
    (2) One-half of the minimum tensile strength across the welded seam 
determined in paragraph (l) of this section.
    (3) One-half of the minimum tensile strength of the base metal 
determined as required in paragraph (j) of this section.
    (4) The yield strength of the base metal determined as required in 
paragraph (l) of this section.
    (5) Further provided that wall stress for cylinders having 
longitudinal seams may not exceed 85 percent of the above value, 
whichever applies.
    (6) Calculation must be made by the following formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

where:

S = wall stress in pounds psi;
P = minimum test pressure prescribed for pressure test in psig;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. Heat treatment is not permitted.
    (h) Openings in cylinder. Openings in cylinders must conform to the 
following:
    (1) Openings are permitted in heads only. They must be circular and 
may not exceed 3 inches in diameter or one third of the cylinder 
diameter, whichever is less. Each opening in the cylinder must be 
provided with a fitting, boss or pad, either integral with, or securely 
attached to, the cylinder body by fusion welding. Attachments to a 
fitting, boss or pad may be made by welding, brazing, mechanical 
attachment, or threading.
    (2) Threads must comply with the following:
    (i) Threads must be clean-cut, even, without checks and cut to 
gauge.
    (ii) Taper threads to be of a length not less than that specified 
for NPT.
    (iii) Straight threads must have at least 4 engaged threads, tight 
fit and calculated shear strength at least 10 times the test pressure of 
the cylinder. Gaskets, which prevent leakage and are inert to the 
hazardous material, are required.
    (i) Pressure test. Each cylinder, before insulating and jacketing, 
must be examined under a pressure of at least 2 times the service 
pressure maintained for at least 30 seconds without evidence of leakage, 
visible distortion or other defect. The pressure gauge must permit 
reading to an accuracy of 1 percent.
    (j) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, and elongation as follows:
    (1) The test is required on 2 specimens selected from material of 
each heat and in the same condition as that in the completed cylinder.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
a gauge length of 2 inches with width not over 1\1/2\ inches, or a gauge 
length at least 24 times thickness with a width not over 6 times 
thickness (authorized when cylinder wall is not over \1/16\ inch thick).
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within one inch of each end of the reduced 
section.
    (iii) When size of the cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold by pressure only, not by blows. 
When specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.

[[Page 61]]

    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load''), corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic expansion of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on the elastic modulus of 
the material used. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain 
reference must be set while the specimen is under a stress of 12,000 psi 
and the strain indicator reading being set at the calculated 
corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (k) Acceptable results for physical tests. Physical properties must 
meet the limits specified in paragraph (o)(1), table 1, of this section, 
for the particular steel in the annealed condition. The specimens must 
show at least a 20 percent elongation for a 2-inch gage length. Except 
that the percentage may be reduced numerically by 2 for each 7,500 psi 
increment of tensile strength above 100,000 psi to a maximum of 5 such 
increments. Yield strength and tensile strength must meet the 
requirements of paragraph (o)(1), table 1, of this section.
    (l) Tests of welds. Welds must be tested as follows:
    (1) Tensile test. A specimen must be cut from one cylinder of each 
lot of 200 or less, or welded test plate. The welded test plate must be 
of one of the heats in the lot of 200 or less which it represents, in 
the same condition and approximately the same thickness as the cylinder 
wall except that it may not be of a lesser thickness than that required 
for a quarter size Charpy impact specimen. The weld must be made by the 
same procedures and subjected to the same heat treatment as the major 
weld on the cylinder. The specimen must be taken across the major seam 
and must be prepared in accordance with and must meet the requirements 
of CGA Pamphlet C-3. Should this specimen fail to meet the requirements, 
specimens may be taken from two additional cylinders or welded test 
plates from the same lot and tested. If either of the latter specimens 
fails to meet the requirements, the entire lot represented must be 
rejected.
    (2) Guided bend test. A ``root'' bend test specimen must be cut from 
the cylinder or welded test plate, used for the tensile test specified 
in paragraph (l)(1) of this section and from any other seam or 
equivalent welded test plate if the seam is welded by a procedure 
different from that used for the major seam. Specimens must be taken 
across the particular seam being tested and must be prepared and tested 
in accordance with and must meet the requirements of CGA Pamphlet C-3.
    (3) Alternate guided-bend test. This test may be used and must be as 
specified in CGA Pamphlet C-3. The specimen must be bent until the 
elongation at the outer surface, adjacent to the root of the weld, 
between the lightly scribed gage lines a to b, is at least 20 percent, 
except that this percentage may be reduced for steels having a tensile 
strength in excess of 100,000 psig, as provided in paragraph (c) of this 
section.
    (4) Impact tests. One set of three impact test specimens (for each 
test) must be prepared and tested for determining the impact properties 
of the deposited weld metal--
    (i) As part of the qualification of the welding procedure.
    (ii) As part of the qualification of the operators.
    (iii) For each ``heat'' of welding rodor wire used.

[[Page 62]]

    (iv) For each 1,000 feet of weld made with the same heat of welding 
rod or wire.
    (v) All impact test specimens must be of the charpy type, keyhole or 
milled U-notch, and must conform in all respects to ASTM E 23 (IBR, see 
Sec. 171.7 of this subchapter). Each set of impact specimens must be 
taken across the weld and have the notch located in the weld metal. When 
the cylinder material thickness is 2.5 mm or thicker, impact specimens 
must be cut from a cylinder or welded test plate used for the tensile or 
bend test specimens. The dimension along the axis of the notch must be 
reduced to the largest possible of 10 mm, 7.5 mm, 5 mm or 2.5 mm, 
depending upon cylinder thickness. When the material in the cylinder or 
welded test plate is not of sufficient thickness to prepare 2.5 mm 
impact test specimens, 2.5 mm specimens must be prepared from a welded 
test plate made from \1/8\ inch thick material meeting the requirements 
specified in paragraph (o)(1), table 1, of this section and having a 
carbon analysis of .05 minimum, but not necessarily from one of the 
heats used in the lot of cylinders. The test piece must be welded by the 
same welding procedure as used on the particular cylinder seam being 
qualified and must be subjected to the same heat treatment.
    (vi) Impact test specimens must be cooled to the design service 
temperature. The apparatus for testing the specimens must conform to 
requirements of ASTM Standard E 23. The test piece, as well as the 
handling tongs, must be cooled for a length of time sufficient to reach 
the service temperature. The temperature of the cooling device must be 
maintained within a range of plus or minus 3 [deg]F. The specimen must 
be quickly transferred from the cooling device to the anvil of the 
testing machine and broken within a time lapse of not more than six 
seconds.
    (vii) The impact properties of each set of impact specimens may not 
be less than the values in the following table:

------------------------------------------------------------------------
                                                 Minimum       Minimum
                                              impact value  impact value
                                              required for  permitted on
              Size of specimen                avg. of each   one only of
                                              set of three    a set of
                                                specimens    three (ft.-
                                                (ft.-lb.)       lb.)
------------------------------------------------------------------------
10 mmx10 mm.................................          15            10
10 mmx7.5 mm................................          12.5           8.5
10 mmx5 mm..................................          10             7.0
10 mmx2.5 mm................................           5             3.5
------------------------------------------------------------------------

    (viii) When the average value of the three specimens equals or 
exceeds the minimum value permitted for a single specimen and the value 
for more than one specimen is below the required average value, or when 
the value for one specimen is below the minimum value permitted for a 
single specimen, a retest of three additional specimens must be made. 
The value of each of these retest specimens must equal or exceed the 
required average value. When an erratic result is caused by a defective 
specimen, or there is uncertainty in test procedure, a retest is 
authorized.
    (m) Radiographic examination. Cylinders must be subject to a 
radiographic examination as follows:
    (1) The techniques and acceptability of radiographic inspection must 
conform to the standards set forth in CGA Pamphlet C-3.
    (2) One finished longitudinal seam must be selected at random from 
each lot of 100 or less successively produced and be radiographed 
throughout its entire length. Should the radiographic examination fail 
to meet the requirements of paragraph (m)(1) of this section, two 
additional seams of the same lot must be examined, and if either of 
these fail to meet the requirements of (m)(1) of this section, only 
those passing are acceptable.
    (n) Rejected cylinders. Reheat treatment of rejected cylinders is 
authorized. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Welds may be repaired by suitable methods of fusion 
welding.
    (o) Authorized materials of construction. Authorized materials of 
construction are as follows:
    (1) Inner containment vessel (cylinder). Electric furnace steel of 
uniform quality must be used. Chemical analysis must conform to ASTM A 
240/A 240M (IBR, see Sec. 171.7 of this subchapter),

[[Page 63]]

Type 304 stainless steel. Chemical analysis must conform to ASTM A240, 
Type 304 Stainless Steel. A heat of steel made under table 1 and table 2 
in this paragraph (o)(1) is acceptable, even though its check chemical 
analysis is slightly out of the specified range, if it is satisfactory 
in all other respects, provided the tolerances shown in table 3 in this 
paragraph (o)(1) are not exceeded. The following chemical analyses and 
physical properties are authorized:

                      Table 1--Authorized Materials
------------------------------------------------------------------------
                                           Chemical analysis, limits in
              Designation                            percent
------------------------------------------------------------------------
Carbon \1\.............................  0.08 max.
Manganese..............................  2.00 max.
Phosphorus.............................  0.045 max.
Sulphur................................  0.030 max.
Silicon................................  1.00 max.
Nickel.................................  8.00-10.50.
Chromium...............................  18.00-20.00.
Molybdenum.............................  None.
Titanium...............................  None.
Columbium..............................  None.
------------------------------------------------------------------------
\1\ The carbon analysis must be reported to the nearest hundredth of one
  percent.


                      Table 2--Physical Properties
------------------------------------------------------------------------
                                                               Physical
                                                              properties
                                                              (annealed)
------------------------------------------------------------------------
Tensile strength, p.s.i. (minimum)..........................    75,000
Yield strength, p.s.i. (minimum)............................    30,000
Elongation in 2 inches (minimum) percent....................        30.0
Elongation other permissible gauge lengths (minimum) percent        15.0
------------------------------------------------------------------------


                   Table 3--Check Analysis Tolerances
------------------------------------------------------------------------
                                                              Tolerance
                                                              over the
                                                               maximum
            Elements              Limit or specified range    limit or
                                         (percent)            under the
                                                               minimum
                                                                limit
------------------------------------------------------------------------
Carbon.........................  To 0.030, incl...........         0.005
                                 Over 0.30 to 0.20, incl..         0.01
Manganese......................  To 1.00 incl.............          .03
                                 Over 1.00 to 3.00, incl..         0.04
Phosphorus \1\.................  To 0.040, incl...........         0.005
                                 Over 0.040 to 0.020 incl.         0.010
Sulphur........................  To .40 incl..............         0.005
Silicon........................  To 1.00, incl............         0.05
Nickel.........................  Over 5.00 to 10.00, incl.         0.10
                                 Over 10.00 to 20.00, incl         0.15
Chromium.......................  Over 15.00 to 20.00, incl         0.20
------------------------------------------------------------------------
\1\ Rephosphorized steels not subject to check analysis for phosphorus.

    (2) Outer jacket. (i) Nonflammable cryogenic liquids. Cylinders 
intended for use in the transportation of nonflammable cryogenic liquid 
must have an outer jacket made of steel or aluminum.
    (ii) Flammable cryogenic liquids. Cylinders intended for use in the 
transportation of flammable cryogenic liquid must have an outer jacket 
made of steel.
    (p) Markings. (1) Markings must be stamped plainly and permanently 
on shoulder or top head of jacket or on a permanently attached plate or 
head protective ring.
    (2) The letters ``ST'', followed by the design service temperature 
(for example, ST-423F), must be marked on cylinders having a design 
service temperature of colder than minus 320 [deg]F only. Location to be 
just below the DOT mark.
    (3) The maximum weight of contents, in pounds (for example, ``Max. 
Content 51 ''), must be marked on cylinders having a design 
service temperature colder than minus 320 [deg]F only. Location to be 
near symbol.
    (4) Special orientation instructions must be marked on the cylinder 
(for example, THIS END UP), if the cylinder is used in an orientation 
other than vertical with openings at the top of the cylinder.
    (5) If the jacket of the cylinder is constructed of aluminum, the 
letters ``AL'' must be marked after the service pressure marking. 
Example: DOT-4L150 AL.
    (6) Except for serial number and jacket material designation, each 
marking prescribed in this paragraph (p) must be duplicated on each 
cylinder by any suitable means.
    (q) Inspector's report. In addition to the information required by 
Sec. 178.35, the inspector's reports must contain information on:
    (1) The jacket material and insulation type;
    (2) The design service temperature

([deg]F); and
    (3) The impact test results, on a lot basis.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386-
45388, Aug. 28, 2001; 67 FR 51653, Aug. 8, 2002; 68 FR 75748, Dec. 31, 
2003]

[[Page 64]]



Sec. 178.58  Specification 4DA welded steel cylinders for aircraft
use.

    (a) Type, size, and service pressure. A DOT 4DA is a welded steel 
sphere (two seamless hemispheres) or a circumferentially welded cylinder 
(two seamless drawn shells) with a water capacity not over 100 pounds 
and a service pressure of at least 500 but not over 900 psig.
    (b) Steel. Open-hearth or electric steel of uniform quality must be 
used. A heat of steel made under table 1 in this paragraph (b), check 
chemical analysis of which is slightly out of the specified range, is 
acceptable, if satisfactory in all other respects, provided the 
tolerances shown in table 2 in this paragraph (b) are not exceeded 
except as approved by the Associate Administrator. The following 
chemical analyses are authorized:

                      Table 1--Authorized Materials
------------------------------------------------------------------------
                   4130                                Percent
------------------------------------------------------------------------
Carbon....................................  0.28/0.33.
Manganese.................................  0.40/0.60.
Phosphorus................................  0.040 max.
Sulfur....................................  0.040 max.
Silicon...................................  0.15/0.35.
Chromium..................................  0.80/1.10.
Molybdenum................................  0.15/0.25.
------------------------------------------------------------------------


                                       Table 2--Check Analysis Tolerances
----------------------------------------------------------------------------------------------------------------
                                                                  Tolerance (percent) over the maximum limit or
                                           Limit or maximum                  under the minimum limit
               Element                   specified (percent)   -------------------------------------------------
                                                                  Under minimum limit       Over maximum limit
----------------------------------------------------------------------------------------------------------------
Carbon...............................  Over 0.15 to 0.40 incl.  .03....................  .04
Manganese............................  To 0.60 incl...........  .03....................  .03
Phosphorus\1\........................  All ranges.............  .......................  .01
Sulphur..............................  All ranges.............  .......................  .01
Silicon..............................  To 0.30 incl...........  .02....................  .03
                                       Over 0.30 to 1.00 incl.  .05....................  .05
Chromium.............................  To 0.90 incl...........  .03....................  .03
                                       Over 0.90 to 2.10 incl.  .05....................  .05
Molybdenum...........................  To 0.20 incl...........  .01....................  .01
                                       Over 0.20 to 0.40, incl  .02....................  .02
----------------------------------------------------------------------------------------------------------------
\1\ Rephosphorized steels not subject to check analysis for phosphorus.

    (c) Identification of material. Materials must be identified by any 
suitable method except that plates and billets for hot-drawn containers 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured in accordance with 
the following requirements:
    (1) By best appliances and methods. No defect is acceptable that is 
likely to weaken the finished container appreciably. A reasonably smooth 
and uniform surface finish is required. No abrupt change in wall 
thickness is permitted. Welding procedures and operators must be 
qualified in accordance with CGA Pamphlet C-3 (IBR, see Sec. 171.7 of 
this subchapter).
    (2) All seams of the sphere or cylinders must be fusion welded. 
Seams must be of the butt or joggle butt type and means must be provided 
for accomplishing complete penetration of the joint.
    (e) Welding. Attachments to the container are authorized by fusion 
welding provided that such attachments are made of weldable steel, the 
carbon content of which may not exceed 0.25 percent except in the case 
of 4130 steel.
    (f) Wall thickness. The minimum wall thickness must be such that the 
wall stress at the minimum specified test pressure may not exceed 67 
percent of the minimum tensile strength of the steel as determined from 
the physical and burst tests required and may not be over 70,000 p.s.i. 
For any diameter container, the minimum wall thickness is 0.040 inch. 
Calculations must be made by the formulas in (f)(1) or (f)(2) of this 
section:
    (1) Calculation for a sphere must be made by the following formula:

S = PD / 4tE

Where:

S = wall stress in pounds psi;
P = test pressure prescribed for water jacket test, i.e., at least 2 
          times service pressure, in psig;
D = outside diameter in inches;
t = minimum wall thickness in inches;
E = 0.85 (provides 85 percent weld efficiency factor which must be 
          applied in the girth weld area and heat affected zones which 
          zone must extend a distance of 6 times wall thickness from 
          center line of weld);
E = 1.0 (for all other areas).

    (2) Calculation for a cylinder must be made by the following 
formula:

S = [P(1.3D \2\ + 0.4d \2\)] / (D \2\ - d \2\)

Where:

S = wall stress in pounds psi;

[[Page 65]]

P = test pressure prescribed for water jacket test, i.e., at least 2 
          times service pressure, in psig;
D = outside diameter in inches;
d = inside diameter in inches.

    (g) Heat treatment. The completed containers must be uniformly and 
properly heat-treated prior to tests. Heat-treatment of containers of 
the authorized analysis must be as follows:
    (1) All containers must be quenched by oil, or other suitable medium 
except as provided in paragraph (g)(4) of this section.
    (2) The steel temperature on quenching must be that recommended for 
the steel analysis, but may not exceed 1,750 [deg]F.
    (3) The steel must be tempered at the temperature most suitable for 
the analysis except that in no case shall the tempering temperature be 
less than 1,000 [deg]F.
    (4) The steel may be normalized at a temperature of 1,650 [deg]F 
instead of being quenched, and containers so normalized need not be 
tempered.
    (5) All cylinders, if water quenched or quenched with a liquid 
producing a cooling rate in excess of 80 percent of the cooling rate of 
water, must be inspected by the magnetic particle or dye penetrant 
method to detect the presence of quenching cracks. Any cylinder found to 
have a quench crack must be rejected and may not be requalified.
    (h) Openings in container. Openings in the container must comply 
with the following requirements:
    (1) Each opening in the container must be provided with a fitting, 
boss, or pad of weldable steel securely attached to the container by 
fusion welding.
    (2) Attachments to a fitting, boss, or pad must be adequate to 
prevent leakage. Threads must comply with the following:
    (i) Threads must be clean cut, even, without checks, and tapped to 
gauge.
    (ii) Taper threads to be of length not less than as specified for 
American Standard taper pipe threads.
    (iii) Straight threads, having at least 4 engaged threads, to have 
tight fit and calculated shear strength at least 10 times the test 
pressure of the container; gaskets required, adequate to prevent 
leakage.
    (i) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to accuracy either of 1 percent or 0.1 cubic 
centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure. If, due to failure of the test 
apparatus, the test pressure cannot be maintained, the test may be 
repeated at a pressure increased by 10 percent or 100 psig, whichever is 
the lower.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) Each container must be tested to at least 2 times service 
pressure.
    (j) Burst test. One container taken at random out of 200 or less 
must be hydrostatically tested to destruction. The rupture pressure must 
be included as part of the inspector's report.
    (k) Flattening test. Spheres and cylinders must be subjected to a 
flattening test as follows:
    (1) Flattening test for spheres. One sphere taken at random out of 
each lot of 200 or less must be subjected to a flattening test as 
follows:
    (i) The test must be performed after the hydrostatic test.
    (ii) The test must be at the weld between the parallel steel plates 
on a press with a welded seam, at right angles to the plates. Any 
projecting appurtenances may be cut off (by mechanical means only) prior 
to crushing.
    (2) Flattening test for cylinders. One cylinder taken at random out 
of each lot of 200 or less, must be subjected to a flattening test as 
follows:
    (i) The test must be performed after the hydrostatic test.
    (ii) The test cylinder must be placed between wedge-shaped knife 
edges having a 60[deg] angle, rounded to a \1/2\-inch radius.

[[Page 66]]

    (l) Radiographic inspection. Radiographic examinations is required 
on all welded joints which are subjected to internal pressure, except 
that at the discretion of the disinterested inspector, openings less 
than 25 percent of the sphere diameter need not be subjected to 
radiographic inspection. Evidence of any defects likely to seriously 
weaken the container must be cause for rejection.
    (m) Physical test and specimens for spheres and cylinders. Spheres 
and cylinders must be subjected to a physical test as follows:
    (1) A physical test for a sphere is required on 2 specimens cut from 
a flat representative sample plate of the same heat taken at random from 
the steel used to produce the sphere. This flat steel from which the 2 
specimens are to be cut must receive the same heat-treatment as the 
spheres themselves. Sample plates to be taken for each lot of 200 or 
less spheres.
    (2) Specimens for spheres have a gauge length of 2 inches with a 
width not over 1\1/2\ inches, or a gauge length at least 24 times 
thickness with a width not over 6 times thickness is authorized when 
wall of sphere is not over \3/16\ inch thick.
    (3) A physical test for cylinders is required on 2 specimens cut 
from 1 cylinder taken at random out of each lot of 200 or less.
    (4) Specimens for cylinder must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
a gauge length of 2 inches with a width not over 1\1/2\ inches, a gauge 
length at least 24 times thickness with a width not over 6 times 
thickness is authorized when a cylinder wall is not over \3/16\ inch 
thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within 1 inch of each end of the reduced 
section.
    (iii) Heating of a specimen for any purpose is not authorized.
    (5) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
percent offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi and the strain 
indicator reading being set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (n) Acceptable results for physical, flattening, and burst tests. 
The following are acceptable results of the physical, flattening and 
burst test:
    (1) Elongation must be at least 20 percent for a 2-inch gauge length 
or 10 percent in other cases.
    (2) Flattening is required to 50 percent of the original outside 
diameter without cracking.
    (3) Burst pressure must be at least 3 times service pressure.
    (o) Rejected containers. Reheat-treatment of rejected cylinders is 
authorized. Subsequent thereto, containers must pass all prescribed 
tests to be acceptable. Repair of welded seams by welding prior to 
reheat-treatment is authorized.
    (p) Marking. Markings on each container must be stamped plainly and 
permanently on a permanent attachment or on a metal nameplate 
permanently secured to the container by means other than soft solder.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, 
45388, Aug. 28, 2001; 67 FR 51654, Aug. 8, 2002; 67 FR 61015, Sept. 27, 
2002; 68 FR 75748, Dec. 31, 2003]

[[Page 67]]



Sec. 178.59  Specification 8 steel cylinders with porous fillings
for acetylene.

    (a) Type and service pressure. A DOT 8 cylinder is a seamless 
cylinder with a service pressure of 250 psig. The following steel is 
authorized:
    (1) A longitudinal seam if forge lap welded;
    (2) Attachment of heads by welding or by brazing by dipping process; 
or
    (3) A welded circumferential body seam if the cylinder has no 
longitudinal seam.
    (b) Steel. Open-hearth, electric or basic oxygen process steel of 
uniform quality must be used. Content percent may not exceed the 
following: Carbon, 0.25; phosphorus, 0.045; sulphur, 0.050.
    (c) Identification of steel. Materials must be identified by any 
suitable method except that plates and billets for hot-drawn cylinders 
must be marked with the heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is acceptable that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. Welding procedures and operators 
must be qualified in accordance with CGA Pamphlet C-3 (IBR, see Sec. 
171.7 of this subchapter).
    (e) Exposed bottom welds. Exposed bottom welds on cylinders over 18 
inches long must be protected by footrings.
    (f) Heat treatment. Body and heads formed by drawing or pressing 
must be uniformly and properly heat treated prior to tests.
    (g) Openings. Openings in the cylinders must comply with the 
following:
    (1) Standard taper pipe threads are required;
    (2) Length may not be less than as specified for American Standard 
pipe threads; tapped to gauge; clean cut, even, and without checks.
    (h) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) One cylinder out of each lot of 200 or less must be 
hydrostatically tested to at least 750 psig. Cylinders not so tested 
must be examined under pressure of between 500 and 600 psig and show no 
defect. If hydrostatically tested cylinder fails, each cylinder in the 
lot may be hydrostatically tested and those passing are acceptable.
    (i) Leakage test. Cylinders with bottoms closed in by spinning must 
be subjected to a leakage test by setting the interior air or gas 
pressure to not less than the service pressure. Cylinders which leak 
must be rejected.
    (j) Physical test. A physical test must be conducted as follows:
    (1) The test is required on 2 specimens cut longitudinally from 1 
cylinder or part thereof taken at random out of each lot of 200 or less, 
after heat treatment.
    (2) Specimens must conform to a gauge length of 8 inches with a 
width not over 1\1/2\ inches, a gauge length of 2 inches with width not 
over 1\1/2\, or a gauge length at least 24 times thickness with a width 
not over 6 times thickness is authorized when a cylinder wall is not 
over \3/16\ inch thick.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the

[[Page 68]]

gauge length under appropriate load and adding thereto 0.2 percent of 
the gauge length. Elastic extension calculations must be based on an 
elastic modulus of 30,000,000. In the event of controversy, the entire 
stress-strain diagram must be plotted and the yield strength determined 
from the 0.2 offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi and the strain 
indicator reading being set at the calculated corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (4) Yield strength may not exceed 73 percent of tensile strength. 
Elongation must be at least 40 percent in 2 inch or 20 percent in other 
cases.
    (k) Rejected cylinders. Reheat treatment of rejected cylinder is 
authorized. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding is authorized.
    (l) Porous filling. (1) Cylinders must be filled with a porous 
material in accordance with the following:
    (i) The porous material may not disintegrate or sag when wet with 
solvent or when subjected to normal service;
    (ii) The porous filling material must be uniform in quality and free 
of voids, except that a well drilled into the filling material beneath 
the valve is authorized if the well is filled with a material of such 
type that the functions of the filling material are not impaired;
    (iii) Overall shrinkage of the filling material is authorized if the 
total clearance between the cylinder shell and filling material, after 
solvent has been added, does not exceed \1/2\ of 1 percent of the 
respective diameter or length, but not to exceed \1/8\ inch, measured 
diametrically and longitudinally;
    (iv) The clearance may not impair the functions of the filling 
material;
    (v) The installed filling material must meet the requirements of CGA 
C-12 (IBR, see Sec. 171.7 of this subchapter); and
    (vi) Porosity of filling material may not exceed 80 percent except 
that filling material with a porosity of up to 92 percent may be used 
when tested with satisfactory results in accordance with CGA Pamphlet C-
12.
    (2) When the porosity of each cylinder is not known, a cylinder 
taken at random from a lot of 200 or less must be tested for porosity. 
If the test cylinder fails, each cylinder in the lot may be tested 
individually and those cylinders that pass the test are acceptable.
    (3) For filling that is molded and dried before insertion in 
cylinders, porosity test may be made on a sample block taken at random 
from material to be used.
    (4) The porosity of the filling material must be determined. The 
amount of solvent at 70 [deg]F for a cylinder:
    (i) Having shell volumetric capacity above 20 pounds water capacity 
(nominal) may not exceed the following:

------------------------------------------------------------------------
                                                               Maximum
                                                               acetone
                                                               solvent
                 Percent porosity of filler                    percent
                                                                shell
                                                             capacity by
                                                                volume
------------------------------------------------------------------------
90 to 92...................................................         43.4
87 to 90...................................................         42.0
83 to 87...................................................         40.0
80 to 83...................................................         38.6
75 to 80...................................................         36.2
70 to 75...................................................         33.8
65 to 70...................................................         31.4
------------------------------------------------------------------------

    (ii) Having volumetric capacity of 20 pounds or less water capacity 
(nominal), may not exceed the following:

------------------------------------------------------------------------
                                                               Maximum
                                                               acetone
                                                               solvent
                 Percent porosity of filler                    percent
                                                                shell
                                                             capacity by
                                                                volume
------------------------------------------------------------------------
90 to 92...................................................         41.8
83 to 90...................................................         38.5
80 to 83...................................................         37.1
75 to 80...................................................         34.8
70 to 75...................................................         32.5
65 to 70...................................................         30.2
------------------------------------------------------------------------

    (m) Tare weight. The tare weight is the combined weight of the 
cylinder proper, porous filling, valve, and solvent, without removable 
cap.
    (n) Duties of inspector. In addition to the requirements of Sec. 
178.35, the inspector is required to--
    (1) Certify chemical analyses of steel used, signed by manufacturer 
thereof; also verify by, check analyses of samples taken from each heat 
or from 1 out

[[Page 69]]

of each lot of 200 or less, plates, shells, or tubes used.
    (2) Verify compliance of cylinder shells with all shell 
requirements; inspect inside before closing in both ends; verify heat 
treatment as proper; obtain all samples for all tests and for check 
analyses; witness all tests; verify threads by gauge; report volumetric 
capacity and minimum thickness of wall noted.
    (3) Prepare report on manufacture of steel shells in form prescribed 
in Sec. 178.35. Furnish one copy to manufacturer and three copies to 
the company that is to complete the cylinders.
    (4) Determine porosity of filling and tare weights; verify 
compliance of marking with prescribed requirements; obtain necessary 
copies of steel shell reports; and furnish complete reports required by 
this specification to the person who has completed the manufacture of 
the cylinders and, upon request, to the purchaser. The test reports must 
be retained by the inspector for fifteen years from the original test 
date of the cylinder.
    (o) Marking. (1) Marking on each cylinder must be stamped plainly 
and permanently on or near the shoulder, top head, neck or valve 
protection collar which is permanently attached to the cylinder and 
forming integral part thereof.
    (2) Tare weight of cylinder, in pounds and ounces, must be marked on 
the cylinder.
    (3) Cylinders, not completed, when delivered must each be marked for 
identification of each lot of 200 or less.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, 
Aug. 28, 2001; 67 FR 61016, Sept. 27, 2002; 67 FR 51654, Aug. 8, 2002; 
68 FR 75748, 75749, Dec. 31, 2003]



Sec. 178.60  Specification 8AL steel cylinders with porous fillings
for acetylene.

    (a) Type and service pressure. A DOT 8AL cylinder is a seamless 
steel cylinder with a service pressure of 250 psig. However, the 
attachment of heads by welding or by brazing by dipping process and a 
welded circumferential body seam is authorized. Longitudinal seams are 
not authorized.
    (b) Authorized steel. The authorized steel is as specified in table 
I of appendix A to this part.
    (c) Identification of steel. Material must be identified by any 
suitable method except that plates and billets for hot-drawn cylinders 
must be marked with heat number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. Welding procedures and operators 
must be qualified in accordance with CGA Pamphlet C-3 (IBR, see Sec. 
171.7 of this subchapter).
    (e) Footrings. Exposed bottom welds on cylinders over 18 inches long 
must be protected by footrings.
    (f) Welding or brazing. Welding or brazing for any purpose 
whatsoever is prohibited except as follows:
    (1) The attachment to the tops or bottoms of cylinders of neckrings, 
footrings, handlers, bosses, pads, and valve protecting rings is 
authorized provided that such attachments and the portion of the 
container to which they are attached are made of weldable steel, the 
carbon content of which may not exceed 0.25 percent.
    (2) Heat treatment is not required after welding or brazing weldable 
low carbon parts to attachments, specified in paragraph (f)(1) of this 
section, of similar material which have been previously welded or brazed 
to the top or bottom of cylinders and properly heat treated, provided 
such subsequent welding or brazing does not produce a temperature in 
excess of 400 [deg]F in any part of the top or bottom material.
    (g) Wall thickness; wall stress. The wall thickness/wall stress of 
the cylinder must conform to the following:
    (1) The calculated wall stress at 750 psi may not exceed 35,000 psi, 
or one-half of the minimum ultimate strength of the steel as determined 
in paragraph (l) of this section, whichever value is the smaller. The 
measured wall thickness may not include galvanizing or other protective 
coating.
    (i) Calculation of wall stress must be made by the formula:


[[Page 70]]


S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = wall stress in pounds psi;
P = 750 psig (minimum test pressure);
D = outside diameter in inches;
d = inside diameter in inches.

    (ii) Either D or d must be calculated from the relation D = d + 2t, 
where t = minimum wall thickness.
    (2) Cylinders with a wall thickness less than 0.100 inch, the ratio 
of straight side wall length to outside diameter may not exceed 3.5.
    (3) For cylinders having outside diameter over 5 inches, the minimum 
wall thickness must be 0.087 inch.
    (h) Heat treatment. Each cylinder must be uniformly and properly 
heat treated, prior to tests, by any suitable method in excess of 1100 
[deg]F. Heat treatment must be accomplished after all forming and 
welding operations, except that when brazed joints are used, heat 
treatment must follow any forming and welding operations but may be done 
before, during, or after the brazing operations. Liquid quenching is not 
authorized.
    (i) Openings. Standard taper pipe threads required in all openings. 
The length of the opening may not be less than as specified for American 
Standard pipe threads; tapped to gauge; clean cut, even, and without 
checks.
    (j) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit 
reading of total expansion to an accuracy of either 1 percent or 0.1 
cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat-treatment and previous to the official test may not 
exceed 90 percent of the test pressure.
    (3) Permanent volumetric expansion may not exceed 10 percent of 
total volumetric expansion at test pressure.
    (4) One cylinder out of each lot of 200 or less must be 
hydrostatically tested to at least 750 psig. Cylinders not so tested 
must be examined under pressure of between 500 and 600 psig and show no 
defect. If a hydrostatically tested cylinder fails, each cylinder in the 
lot may be hydrostatically tested and those passing are acceptable.
    (k) Leakage test. Cylinders with bottoms closed in by spinning must 
be leakage tested by setting the interior air or gas pressure at not 
less than the service pressure. Any cylinder that leaks must be 
rejected.
    (l) Physical test. A physical test must be conducted as follows;
    (1) The test is required on 2 specimens cut longitudinally from 1 
cylinder or part thereof taken at random out of each lot of 200 or less, 
after heat treatment.
    (2) Specimens must conform to a gauge length of 8 inches with a 
width not over 1\1/2\ inches, a gauge length 2 inches with a width not 
over 1\1/2\ inches, or a gauge length at least 24 times thickness with a 
width not over 6 times thickness is authorized when a cylinder wall is 
not over \3/16\ inch thick.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``offset'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load'') corresponding to the stress at which the 
0.2 percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2 
offset.
    (iii) For the purpose of strain measurement, the initial strain must 
be set while the specimen is under a stress of 12,000 psi, the strain 
indicator reading being set at the calculated corresponding strain.

[[Page 71]]

    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (m) Elongation. Physical test specimens must show at least a 40 
percent elongation for a 2 inch gauge length or at least a 20 percent 
elongation in other cases. Except that these elongation percentages may 
be reduced numerically by 2 for 2 inch specimens and 1 in other cases 
for each 7,500 psi increment of tensile strength above 50,000 psi to a 
maximum of four such increments.
    (n) Weld tests. Specimens taken across the circumferentially welded 
seam must be cut from one cylinder taken at random from each lot of 200 
or less cylinders after heat treatment and must pass satisfactorily the 
following tests:
    (1) Tensile test. A specimen must be cut from one cylinder of each 
lot of 200 or less, or welded test plate. The specimen must be taken 
from across the major seam and must be prepared and tested in accordance 
with and must meet the requirements of CGA Pamphlet C-3. Should this 
specimen fail to meet the requirements, specimens may be taken from two 
additional cylinders or welded test plates from the same lot and tested. 
If either of the latter specimens fail to meet the requirements, the 
entire lot represented must be rejected.
    (2) Guided bend test. A root bend test specimen must be cut from the 
cylinder or welded test plate, used for the tensile test specified in 
paragraph (n)(1) of this section. Specimens must be prepared and tested 
in accordance with and must meet the requirements of CGA Pamphlet C-3.
    (3) Alternate guided-bend test. This test may be used and must be as 
required by CGA Pamphlet C-3. The specimen must be bent until the 
elongation at the outer surface, adjacent to the root of the weld, 
between the lightly scribed gage lines-a to b, must be at least 20 
percent, except that this percentage may be reduced for steels having a 
tensile strength in excess of 50,000 psi, as provided in paragraph (m) 
of this section.
    (o) Rejected cylinders. Reheat treatment of rejected cylinders is 
authorized. Subsequent thereto, cylinders must pass all prescribed tests 
to be acceptable. Repair by welding is authorized.
    (p) Porous filling. (1) Cylinders must be filled with a porous 
material in accordance with the following:
    (i) The porous material may not disintegrate or sag when wet with 
solvent or when subjected to normal service;
    (ii) The filling material must be uniform in quality and free of 
voids, except that a well drilled into the filling material beneath the 
valve is authorized if the well is filled with a material of such type 
that the functions of the filling material are not impaired;
    (iii) Overall shrinkage of the filling material is authorized if the 
total clearance between the cylinder shell and filling material, after 
solvent has been added, does not exceed \1/2\ of 1 percent of the 
respective diameter or length but not to exceed \1/8\ inch, measured 
diametrically and longitudinally;
    (iv) The clearance may not impair the functions of the filling 
material;
    (v) The installed filling material must meet the requirements of CGA 
C-12 (IBR, see Sec. 171.7 of this subchapter); and
    (vi) Porosity of filling material may not exceed 80 percent except 
that filling material with a porosity of up to 92 percent may be used 
when tested with satisfactory results in accordance with CGA Pamphlet C-
12.
    (2) When the porosity of each cylinder is not known, a cylinder 
taken at random from a lot of 200 or less must be tested for porosity. 
If the test cylinder fails, each cylinder in the lot may be tested 
individually and those cylinders that pass the test are acceptable.
    (3) For filling that is molded and dried before insertion in 
cylinders, porosity test may be made on sample block taken at random 
from material to be used.
    (4) The porosity of the filling material must be determined; the 
amount of solvent at 70 [deg]F for a cylinder:
    (i) Having shell volumetric capacity above 20 pounds water capacity 
(nominal) may not exceed the following:

[[Page 72]]



------------------------------------------------------------------------
                                                 Maximum acetone solvent
           Percent porosity of filler             percent shell capacity
                                                        by volume
------------------------------------------------------------------------
90 to 92.......................................                     43.4
87 to 90.......................................                     42.0
83 to 87.......................................                     40.0
80 to 83.......................................                     38.6
75 to 80.......................................                     36.2
70 to 75.......................................                     33.8
65 to 70.......................................                     31.4
------------------------------------------------------------------------

    (ii) Having volumetric capacity of 20 pounds or less water capacity 
(nominal), may not exceed the following:

------------------------------------------------------------------------
                                                 Maximum acetone solvent
           Percent porosity of filler             percent shell capacity
                                                        by volume
------------------------------------------------------------------------
90 to 92.......................................                     41.8
83 to 90.......................................                     38.5
80 to 83.......................................                     37.1
75 to 80.......................................                     34.8
70 to 75.......................................                     32.5
65 to 70.......................................                     30.2
------------------------------------------------------------------------

    (q) Tare weight. The tare weight is the combined weight of the 
cylinder proper, porous filling, valve, and solvent, but without 
removable cap.
    (r) Duties of inspector. In addition to the requirements of Sec. 
178.35, the inspector shall--
    (1) Certify chemical analyses of steel used, signed by manufacturer 
thereof; also verify by check analyses, of samples taken from each heat 
or from 1 out of each lot of 200 or less plates, shells, or tubes used.
    (2) Verify compliance of cylinder shells with all shell 
requirements, inspect inside before closing in both ends, verify heat 
treatment as proper; obtain all samples for all tests and for check 
analyses, witness all tests; verify threads by gauge, report volumetric 
capacity and minimum thickness of wall noted.
    (3) Report percentage of each specified alloying element in the 
steel. Prepare report on manufacture of steel shells in form prescribed 
in Sec. 178.35. Furnish one copy to manufacturer and three copies to 
the company that is to complete the cylinders.
    (4) Determine porosity of filling and tare weights; verify 
compliance of marking with prescribed requirements; obtain necessary 
copies of steel shell reports prescribed in paragraph (b) of this 
section; and furnish complete test reports required by this 
specification to the person who has completed the manufacturer of the 
cylinders and, upon request, to the purchaser. The test reports must be 
retained by the inspector for fifteen years from the original test date 
of the cylinder.
    (s) Marking. (1) Tare weight of cylinder, in pounds and ounces, must 
be marked on the cylinder.
    (2) Cylinders, not completed, when delivered must each be marked for 
identification of each lot of 200 or less.
    (3) Markings must be stamped plainly and permanently in locations in 
accordance with the following:
    (i) On shoulders and top heads not less than 0.087 inch thick; or
    (ii) On neck, valve boss, valve protection sleeve, or similar part 
permanently attached to the top end of cylinder; or
    (iii) On a plate of ferrous material attached to the top of the 
cylinder or permanent part thereof; the plate must be at least \1/16\ 
inch thick, and must be attached by welding, or by brazing at a 
temperature of at least 1,100 [deg]F throughout all edges of the plate. 
Sufficient space must be left on the plate to provide for stamping at 
least four (4) retest dates.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, 
45388, Aug. 28, 2001; 67 FR 51654, Aug. 8, 2002; 68 FR 75748, 75749, 
Dec. 31, 2003]



Sec. 178.61  Specification 4BW welded steel cylinders with electric-
arc welded longitudinal seam.

    (a) Type, size and service pressure. A DOT 4BW cylinder is a welded 
type steel cylinder with a longitudinal electric-arc welded seam, a 
water capacity (nominal) not over 1,000 pounds and a service pressure at 
least 225 and not over 500 psig gauge. Cylinders closed in by spinning 
process are not authorized.
    (b) Authorized steel. Steel used in the construction of the cylinder 
must conform to the following:
    (1) The body of the cylinder must be constructed of steel conforming 
to the limits specified in table 1 of appendix A to this part.
    (2) Material for heads must meet the requirements of paragraph (a) 
of this section or be open hearth, electric or basic oxygen carbon steel 
of uniform quality. Content percent may not exceed the following: Carbon 
0.25, Manganese 0.60, Phosphorus 0.045, Sulfur

[[Page 73]]

0.050. Heads must be hemispherical or ellipsoidal in shape with a 
maximum ratio of 2.1. If low carbon steel is used, the thickness of such 
heads must be determined by using a maximum wall stress of 24,000 p.s.i. 
in the formula described in paragraph (f)(4) of this section.
    (c) Identification of material. Material must be identified by any 
suitable method.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart and the following:
    (1) No defect is permitted that is likely to weaken the finished 
cylinder appreciably. A reasonably smooth and uniform surface is 
required. Exposed bottom welds on cylinders over 18 inches long must be 
protected by footrings. Minimum thickness of heads may not be less than 
90 percent of the required thickness of the sidewall. Heads must be 
concave to pressure.
    (2) Circumferential seams must be by electric-arc welding. Joints 
must be butt with one member offset (joggle butt) or lap with minimum 
overlap of at least four times nominal sheet thickness.
    (3) Longitudinal seams in shells must conform to the following:
    (i) Longitudinal electric-arc welded seams must be of the butt 
welded type. Welds must be made by a machine process including automatic 
feed and welding guidance mechanisms. Longitudinal seams must have 
complete joint penetration, and must be free from undercuts, overlaps or 
abrupt ridges or valleys. Misalignment of mating butt edges may not 
exceed \1/6\ of nominal sheet thickness or \1/32\ inch whichever is 
less. All joints with nominal sheet thickness up to and including \1/8\ 
inch must be tightly butted. When nominal sheet thickness is greater 
than \1/8\ inch, the joint must be gapped with maximum distance equal to 
one-half the nominal sheet thickness or \1/32\ inch whichever is less. 
Joint design, preparation and fit-up must be such that requirements of 
this paragraph (d) are satisfied.
    (ii) Maximum joint efficiency must be 1.0 when each seam is 
radiographed completely. Maximum joint efficiency must be 0.90 when one 
cylinder from each lot of 50 consecutively welded cylinders is spot 
radiographed. In addition, one out of the first five cylinders welded 
following a shut down of welding operations exceeding four hours must be 
spot radiographed. Spot radiographs, when required, must be made of a 
finished welded cylinder and must include the girth weld for 2 inches in 
both directions from the intersection of the longitudinal and girth 
welds and include at least 6 inches of the longitudinal weld. Maximum 
joint efficacy of 0.75 must be permissible without radiography.
    (4) Welding procedures and operators must be qualified in accordance 
with CGA Pamphlet C-3 (IBR, see Sec. 171.7 of this subchapter).
    (e) Welding of attachments. The attachment to the tops and bottoms 
only of cylinders by welding of neckrings, footrings, handles, bosses, 
pads and valve protection rings is authorized provided that such 
attachments and the portion of the container to which they are attached 
are made of weldable steel, the carbon content of which may not exceed 
0.25 percent.
    (f) Wall thickness. For outside diameters over 6 inches the minimum 
wall thickness must be 0.078 inch. For a cylinder with a wall thickness 
less than 0.100 inch, the ratio of tangential length to outside diameter 
may not exceed 4 to1 (4:1). In any case the minimum wall thickness must 
be such that the wall stress calculated by the formula listed in 
paragraph (f)(4) of this section may not exceed the lesser value of any 
of the following:
    (1) The value referenced in paragraph (b) of this section for the 
particular material under consideration.
    (2) One-half of the minimum tensile strength of the material 
determined as required in paragraph (j) of this section.
    (3) 35,000 psi.
    (4) Stress must be calculated by the following formula:

S = [2P(1.3D\2\ + 0.4d\2\)] / [E(D\2\ - d\2\)]

where:

S = wall stress, psi;
P = service pressure, psig;
D = outside diameter, inches;
d = inside diameter, inches;

[[Page 74]]

E = joint efficiency of the longitudinal seam (from paragraph (d) of 
          this section).

    (g) Heat treatment. Each cylinder must be uniformly and properly 
heat treated prior to test by the applicable method referenced in Table 
1 of appendix A to this part. Heat treatment must be accomplished after 
all forming and welding operations. Heat treatment is not required after 
welding or brazing of weldable low carbon parts to attachments of 
similar material which have been previously welded to the top or bottom 
of cylinders and properly heat treated, provided such subsequent welding 
or brazing does not produce a temperature in excess of 400 [deg]F in any 
part of the top or bottom material.
    (h) Openings in cylinders. Openings in the cylinder must conform to 
the following:
    (1) All openings must be in the heads or bases.
    (2) Openings in cylinders must be provided with adequate fittings, 
bosses, or pads, integral with or securely attached to the cylinder by 
welding.
    (3) Threads must comply with the following:
    (i) Threads must be clean cut and to gauge.
    (ii) Taper threads must be of length not less than as specified for 
American Standard Taper Pipe threads.
    (iii) Straight threads, having at least 4 engaged threads, to have 
tight fit and calculated shear strength at least 10 times the test 
pressure of the cylinder; gaskets required, adequate to prevent leakage.
    (4) Closure of fittings, boss or pads must be adequate to prevent 
leakage.
    (i) Hydrostatic test. Cylinders must withstand a hydrostatic test, 
as follows:
    (1) The test must be by water-jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
readings to an accuracy of 1 percent. The expansion gauge must permit 
readings of total volumetric expansion to an accuracy either of 1 
percent or 0.1 cubic centimeter.
    (2) Pressure must be maintained for at least 30 seconds and 
sufficiently longer to ensure complete expansion. Any internal pressure 
applied after heat treatment and previous to the official test may not 
exceed 90 percent of the test pressure.
    (3) Permanent volumetric expansion may not exceed 10 percent of the 
total volumetric expansion at test pressure.
    (4) Cylinders must be tested as follows:
    (i) At least 1 cylinder selected at random out of each lot of 200 or 
less must be tested as outlined in paragraphs (i)(1), (i)(2), and (i)(3) 
of this section to at least two times service pressure.
    (ii) All cylinders not tested as outlined in paragraph (i)(4)(i) of 
this section must be examined under pressure of at least two times 
service pressure and show no defect.
    (5) One finished cylinder selected at random out of each lot of 500 
or less successively produced must be hydrostatically tested to 4 times 
service pressure without bursting.
    (j) Physical tests. Cylinders must be subjected to a physical test 
as follows:
    (1) Specimens must be taken from one cylinder after heat treatment 
and chosen at random from each lot of 200 or less, as follows:
    (i) Body specimen. One specimen must be taken longitudinally from 
the body section at least 90 degrees away from the weld.
    (ii) Head specimen. One specimen must be taken from either head on a 
cylinder when both heads are made of the same material. However, if the 
two heads are made of differing materials, a specimen must be taken from 
each head.
    (iii) If due to welded attachments on the top head there is 
insufficient surface from which to take a specimen, it may be taken from 
a representative head of the same heat treatment as the test cylinder.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
a gauge length of 2 inches with a width not over 1\1/2\ inches, or a 
gauge length at least 24 times thickness with a width not over 6 times 
thickness is authorized when a cylinder wall is not over \3/16\ inch 
thick.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within 1 inch of each end of the reduced 
section.

[[Page 75]]

    (iii) When size of the cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be straightened or flattened cold, by pressure only, not by blows 
when specimens are so taken and prepared, the inspector's report must 
show in connection with record of physical tests detailed information in 
regard to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by either the ``off-set'' 
method or the ``extension under load'' method as prescribed in ASTM E 8 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) In using the ``extension under load'' method, the total strain 
(or ``extension under load''), corresponding to the stress at which the 
0.2-percent permanent strain occurs may be determined with sufficient 
accuracy by calculating the elastic extension of the gauge length under 
appropriate load and adding thereto 0.2 percent of the gauge length. 
Elastic extension calculations must be based on an elastic modulus of 
30,000,000. In the event of controversy, the entire stress-strain 
diagram must be plotted and the yield strength determined from the 0.2-
percent offset.
    (iii) For the purpose of strain measurement, the initial strain 
reference must be set while the specimen is under a stress of 12,000 psi 
and the strain indicator reading being set at the calculated 
corresponding strain.
    (iv) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (k) Elongation. Physical test specimens must show at least a 40 
percent elongation for a 2-inch gauge length or at least a 20 percent 
elongation in other cases. Except that these elongation percentages may 
be reduced numerically by 2 for 2-inch specimens and by 1 in other cases 
for each 7,500 psi increment of tensile strength above 50,000 psi to a 
maximum of four increments.
    (l) Tests of welds. Welds must be subjected to the following tests:
    (1) Tensile test. A specimen must be cut from one cylinder of each 
lot of 200 or less. The specimen must be taken from across the 
longitudinal seam and must be prepared and tested in accordance with and 
must meet the requirements of CGA Pamphlet C-3.
    (2) Guided bend test. A root test specimen must be cut from the 
cylinder used for the tensile test specified in paragraph (l)(1) of this 
section. Specimens must be taken from across the longitudinal seam and 
must be prepared and tested in accordance with and must meet the 
requirements of CGA Pamphlet C-3.
    (3) Alternate guided bend test. This test may be used and must be as 
required by CGA Pamphlet C-3. The specimen must be bent until the 
elongation at the outer surface, adjacent to the root of the weld, 
between the lightly scribed gauge lines a to b, must be at least 20 
percent, except that this percentage may be reduced for steels having a 
tensile strength in excess of 50,000 psi, as provided in paragraph (k) 
of this section.
    (m) Radiographic examination. Welds of the cylinders must be 
subjected to a radiographic examination as follows:
    (1) Radiographic inspection must conform to the techniques and 
acceptability criteria set forth in CGA Pamphlet C-3. When fluoroscopic 
inspection is used, permanent film records need not be retained.
    (2) Should spot radiographic examination fail to meet the 
requirements of paragraph (m)(1) of this section, two additional welds 
from the same lot of 50 cylinders or less must be examined, and if 
either of these fail to meet the requirements, each cylinder must be 
examined as previously outlined; only those passing are acceptable.
    (n) Rejected cylinders. (1) Unless otherwise stated, if a sample 
cylinder or specimen taken from a lot of cylinders fails the prescribed 
test, then two additional specimens must be selected from the same lot 
and subjected to the prescribed test. If either of these fails the test, 
then the entire lot must be rejected.

[[Page 76]]

    (2) Reheat treatment of rejected cylinders is authorized. Subsequent 
thereto, cylinders must pass all prescribed tests to be acceptable. 
Repair of welded seams by welding is authorized provided that all 
defective metal is cut away and the joint is rewelded as prescribed for 
original welded joints.
    (o) Markings. Markings must be stamped plainly and permanently in 
any of the following locations on the cylinder:
    (1) On shoulders and top heads when they are not less than 0.087-
inch thick.
    (2) On a metal plate attached to the top of the cylinder or 
permanent part thereof; sufficient space must be left on the plate to 
provide for stamping at least six retest dates; the plate must be at 
least \1/16\-inch thick and must be attached by welding, or by brazing. 
The brazing rod is to melt at a temperature of 1100 [deg]F Welding or 
brazing must be along all the edges of the plate.
    (3) On the neck, valve boss, valve protection sleeve, or similar 
part permanently attached to the top of the cylinder.
    (4) On the footring permanently attached to the cylinder, provided 
the water capacity of the cylinder does not exceed 25 pounds.
    (p) Inspector's report. In addition to the information required by 
Sec. 178.35, the inspector's report must indicate the type and amount 
of radiography.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 64 FR 51919, 
Sept. 27, 1999; 66 FR 45386, 45388, Aug. 28, 2001; 67 FR 51654, Aug. 6, 
2002; 67 FR 61016, Sept. 27, 2002; 68 FR 57633, Oct. 6, 2003; 68 FR 
75748, Dec. 31, 2003]



Sec. 178.65  Specification 39 non-reusable (non-refillable) cylinders.

    (a) Type, size, service pressure, and test pressure. A DOT 39 
cylinder is a seamless, welded, or brazed cylinder with a service 
pressure not to exceed 80 percent of the test pressure. Spherical 
pressure vessels are authorized and covered by references to cylinders 
in this specification.
    (1) Size limitation. Maximum water capacity may not exceed: (i) 55 
pounds (1,526 cubic inches) for a service pressure of 500 p.s.i.g. or 
less, and (ii) 10 pounds (277 cubic inches) for a service pressure in 
excess of 500 p.s.i.g.
    (2) Test pressure. The minimum test pressure is the maximum pressure 
of contents at 130 [deg]F or 180 p.s.i.g. whichever is greater.
    (3) Pressure of contents. The term ``pressure of contents'' as used 
in this specification means the total pressure of all the materials to 
be shipped in the cylinder.
    (b) Material; steel or aluminum. The cylinder must be constructed of 
either steel or aluminum conforming to the following requirements:
    (1) Steel. (i) The steel analysis must conform to the following:

------------------------------------------------------------------------
                                                        Ladle     Check
                                                      analysis  analysis
------------------------------------------------------------------------
Carbon, maximum percent.............................      0.12      0.15
Phosphorus, maximum percent.........................       .04       .05
Sulfur, maximum percent.............................       .05       .06
------------------------------------------------------------------------

    (ii) For a cylinder made of seamless steel tubing with integrally 
formed ends, hot drawn, and finished, content percent for the following 
may not exceed: Carbon, 0.55; phosphorous, 0.045; sulfur, 0.050.
    (iii) For non-heat treated welded steel cylinders, adequately killed 
deep drawing quality steel is required.
    (iv) Longitudinal or helical welded cylinders are not authorized for 
service pressures in excess of 500 p.s.i.g.
    (2) Aluminum. Aluminum is not authorized for service pressures in 
excess of 500 psig. The analysis of the aluminum must conform to the 
Aluminum Association standard for alloys 1060, 1100, 1170, 3003, 5052, 
5086, 5154, 6061, and 6063, as specified in its publication entitled 
``Aluminum Standards and Data'' (IBR, see Sec. 171.7 of this 
subchapter).
    (3) Material with seams, cracks, laminations, or other injurious 
defects not permitted.
    (4) Material used must be identified by any suitable method.
    (c) Manufacture. (1) General manufacturing requirements are as 
follows:
    (i) The surface finish must be uniform and reasonably smooth.
    (ii) Inside surfaces must be clean, dry, and free of loose 
particles.
    (iii) No defect of any kind is permitted if it is likely to weaken a 
finished cylinder.
    (2) Requirements for seams:

[[Page 77]]

    (i) Brazing is not authorized on aluminum cylinders.
    (ii) Brazing material must have a melting point of not lower than 
1,000 [deg]F.
    (iii) Brazed seams must be assembled with proper fit to ensure 
complete penetration of the brazing material throughout the brazed 
joint.
    (iv) Minimum width of brazed joints must be at least four times the 
thickness of the shell wall.
    (v) Brazed seams must have design strength equal to or greater than 
1.5 times the minimum strength of the shell wall.
    (vi) Welded seams must be properly aligned and welded by a method 
that provides clean, uniform joints with adequate penetration.
    (vii) Welded joints must have a strength equal to or greater than 
the minimum strength of the shell material in the finished cylinder.
    (3) Attachments to the cylinder are permitted by any means which 
will not be detrimental to the integrity of the cylinder. Welding or 
brazing of attachments to the cylinder must be completed prior to all 
pressure tests.
    (4) Welding procedures and operators must be qualified in accordance 
with CGA Pamphlet C-3 (IBR, see Sec. 171.7 of this subchapter).
    (d) Wall thickness. The minimum wall thickness must be such that the 
wall stress at test pressure does not exceed the yield strength of the 
material of the finished cylinder wall. Calculations must be made by the 
following formulas:
    (1) Calculation of the stress for cylinders must be made by the 
following formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = Wall stress, in psi;
P = Test pressure in psig;
D = Outside diameter, in inches;
d = Inside diameter, in inches.

    (2) Calculation of the stress for spheres must be made by the 
following formula:

S = PD / 4t

Where:

S = Wall stress, in psi;
P = Test pressure i psig;
D = Outside diameter, in inches;
t = Minimum wall thickness, in inches.

    (e) Openings and attachments. Openings and attachments must conform 
to the following:
    (1) Openings and attachments are permitted on heads only.
    (2) All openings and their reinforcements must be within an 
imaginary circle, concentric to the axis of the cylinder. The diameter 
of the circle may not exceed 80 percent of the outside diameter of the 
cylinder. The plane of the circle must be parallel to the plane of a 
circumferential weld and normal to the long axis of the cylinder.
    (3) Unless a head has adequate thickness, each opening must be 
reinforced by a securely attached fitting, boss, pad, collar, or other 
suitable means.
    (4) Material used for welded openings and attachments must be of 
weldable quality and compatible with the material of the cylinder.
    (f) Pressure tests. (1) Each cylinder must be tested at an internal 
pressure of at least the test pressure and must be held at that pressure 
for at least 30 seconds.
    (i) The leakage test must be conducted by submersion under water or 
by some other method that will be equally sensitive.
    (ii) If the cylinder leaks, evidences visible distortion, or any 
other defect, while under test, it must be rejected (see paragraph (h) 
of this section).
    (2) One cylinder taken from the beginning of each lot, and one from 
each 1,000 or less successively produced within the lot thereafter, must 
be hydrostatically tested to destruction. The entire lot must be 
rejected (see paragraph (h) of this section) if:
    (i) A failure occurs at a gage pressure less than 2.0 times the test 
pressure;
    (ii) A failure initiates in a braze or a weld or the heat affected 
zone thereof;
    (iii) A failure is other than in the sidewall of a cylinder 
longitudinal with its long axis; or
    (iv) In a sphere, a failure occurs in any opening, reinforcement, or 
at a point of attachment.
    (3) A ``lot'' is defined as the quantity of cylinders successively 
produced per production shift (not exceeding 10 hours) having identical 
size, design,

[[Page 78]]

construction, material, heat treatment, finish, and quality.
    (g) Flattening test. One cylinder must be taken from the beginning 
of production of each lot (as defined in paragraph (f)(3) of this 
section) and subjected to a flattening test as follows:
    (1) The flattening test must be made on a cylinder that has been 
tested at test pressure.
    (2) A ring taken from a cylinder may be flattened as an alternative 
to a test on a complete cylinder. The test ring may not include the heat 
affected zone or any weld. However, for a sphere, the test ring may 
include the circumferential weld if it is located at a 45 degree angle 
to the ring, 5 degrees.
    (3) The flattening must be between 60 degrees included-angle, wedge 
shaped knife edges, rounded to a 0.5 inch radius.
    (4) Cylinders and test rings may not crack when flattened so that 
their outer surfaces are not more than six times wall thickness apart 
when made of steel or not more than ten times wall thickness apart when 
made of aluminum.
    (5) If any cylinder or ring cracks when subjected to the specified 
flattening test, the lot of cylinders represented by the test must be 
rejected (see paragraph (h) of this section).
    (h) Rejected cylinders. Rejected cylinders must conform to the 
following requirements:
    (1) If the cause for rejection of a lot is determinable, and if by 
test or inspection defective cylinders are eliminated from the lot, the 
remaining cylinders must be qualified as a new lot under paragraphs (f) 
and (g) of this section.
    (2) Repairs to welds are permitted. Following repair, a cylinder 
must pass the pressure test specified in paragraph (f) of this section.
    (3) If a cylinder made from seamless steel tubing fails the 
flattening test described in paragraph (g) of this section, suitable 
uniform heat treatment must be used on each cylinder in the lot. All 
prescribed tests must be performed subsequent to this heat treatment.
    (i) Markings. (1) The markings required by this section must be 
durable and waterproof. The requirements of Sec. 178.35(h) do not apply 
to this section.
    (2) Required markings are as follows:
    (i) DOT-39.
    (ii) NRC.
    (iii) The service pressure.
    (iv) The test pressure.
    (v) The registration number (M****) of the manufacturer.
    (vi) The lot number.
    (vii) The date of manufacture if the lot number does not establish 
the date of manufacture.
    (viii) With one of the following statements:
    (A) For cylinders manufactured prior to October 1, 1996: ``Federal 
law forbids transportation if refilled-penalty up to $25,000 fine and 5 
years imprisonment (49 U.S.C. 1809)'' or ``Federal law forbids 
transportation if refilled-penalty up to $500,000 fine and 5 years 
imprisonment (49 U.S.C. 5124).''
    (B) For cylinders manufactured on or after October 1, 1996: 
``Federal law forbids transportation if refilled-penalty up to $500,000 
fine and 5 years imprisonment (49 U.S.C. 5124).''
    (3) The markings required by paragraphs (i)(2)(i) through (i)(2)(v) 
of this section must be in numbers and letters at least \1/8\ inch high 
and displayed sequentially. For example:

DOT-39 NRC 250/500 M1001.

    (4) No person may mark any cylinder with the specification 
identification ``DOT-39'' unless it was manufactured in compliance with 
the requirements of this section and its manufacturer has a registration 
number (M****) from the Associate Administrator.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 65 FR 58631, 
Sept. 29, 2000; 66 FR 45389, Aug. 28, 2001; 67 FR 51654, Aug. 8, 2002; 
68 FR 75748, 75749, Dec. 31, 2003]



Sec. 178.68  Specification 4E welded aluminum cylinders.

    (a) Type, size and service pressure. A DOT 4E cylinder is a welded 
aluminum cylinder with a water capacity (nominal) of not over 1,000 
pounds and a service pressure of at least 225 to not over 500 psig. The 
cylinder must be constructed of not more than two seamless drawn shells 
with no more than one circumferential weld. The circumferential weld may 
not be closer to the point of tangency of the cylindrical portion with 
the shoulder than 20 times the

[[Page 79]]

cylinder wall thickness. Cylinders or shells closed in by spinning 
process and cylinders with longitudinal seams are not authorized.
    (b) Authorized material. The cylinder must be constructed of 
aluminum of uniform quality. The following chemical analyses are 
authorized:

                      Table 1--Authorized Materials
------------------------------------------------------------------------
                                            Chemical analysis--limits in
               Designation                        percent 5154 \1\
------------------------------------------------------------------------
Iron plus silicon........................  0.45 maximum.
Copper...................................  0.10 maximum.
Manganese................................  0.10 maximum.
Magnesium................................  3.10/3.90.
Chromium.................................  0.15/0.35.
Zinc.....................................  0.20 maximum.
Titanium.................................  0.20 maximum.
Others, each.............................  0.05 maximum.
Others, total............................  0.15 maximum.
Aluminum.................................  remainder.
------------------------------------------------------------------------
\1\ Analysis must regularly be made only for the elements specifically
  mentioned in this table. If, however, the presence of other elements
  is indicated in the course of routine analysis, further analysis
  should be made to determine conformance with the limits specified for
  other elements.

    (c) Identification. Material must be identified by any suitable 
method that will identify the alloy and manufacturer's lot number.
    (d) Manufacture. Cylinders must be manufactured using equipment and 
processes adequate to ensure that each cylinder produced conforms to the 
requirements of this subpart. No defect is permitted that is likely to 
weaken the finished cylinder appreciably. A reasonably smooth and 
uniform surface finish is required. All welding must be by the gas 
shielded arc process.
    (e) Welding. The attachment to the tops and bottoms only of 
cylinders by welding of neckrings or flanges, footrings, handles, bosses 
and pads and valve protection rings is authorized. However, such 
attachments and the portion of the cylinder to which it is attached must 
be made of weldable aluminum alloys.
    (f) Wall thickness. The wall thickness of the cylinder must conform 
to the following:
    (1) The minimum wall thickness of the cylinder must be 0.140 inch. 
In any case, the minimum wall thickness must be such that calculated 
wall stress at twice service pressure may not exceed the lesser value of 
either of the following:
    (i) 20,000 psi.
    (ii) One-half of the minimum tensile strength of the material as 
required in paragraph (j) of this section.
    (2) Calculation must be made by the following formula:

S = [P(1.3D\2\ + 0.4d\2\)] / (D\2\ - d\2\)

Where:

S = wall stress in psi;
P = minimum test pressure prescribed for water jacket test;
D = outside diameter in inches;
d = inside diameter in inches.

    (3) Minimum thickness of heads and bottoms may not be less than the 
minimum required thickness of the side wall.
    (g) Opening in cylinder. Openings in cylinders must conform to the 
following:
    (1) All openings must be in the heads or bases.
    (2) Each opening in cylinders, except those for safety devices, must 
be provided with a fitting, boss, or pad, securely attached to cylinder 
by welding by inert gas shielded arc process or by threads. If threads 
are used, they must comply with the following:
    (i) Threads must be clean-cut, even, without checks and cut to 
gauge.
    (ii) Taper threads to be of length not less than as specified for 
American Standard taper pipe threads.
    (iii) Straight threads, having at least 4 engaged threads, to have 
tight fit and calculated shear strength at least 10 times the test 
pressure of the cylinder; gaskets required, adequate to prevent leakage.
    (3) Closure of a fitting, boss, or pad must be adequate to prevent 
leakage.
    (h) Hydrostatic test. Each cylinder must successfully withstand a 
hydrostatic test, as follows:
    (1) The test must be by water jacket, or other suitable method, 
operated so as to obtain accurate data. The pressure gauge must permit 
reading to an accuracy of 1 percent. The expansion gauge must permit a 
reading of the total expansion to an accuracy either of 1 percent or 0.1 
cubic centimeter.
    (2) Pressure of 2 times service pressure must be maintained for at 
least 30 seconds and sufficiently longer to insure complete expansion. 
Any internal pressure applied previous to the official test may not 
exceed 90 percent of the

[[Page 80]]

test pressure. If, due to failure of the test apparatus, the test 
pressure cannot be maintained, the test may be repeated at a pressure 
increased by 10 percent over the pressure otherwise specified.
    (3) Permanent volumetric expansion may not exceed 12 percent of 
total volumetric expansion at test pressure.
    (4) Cylinders having a calculated wall stress of 18,000 psi or less 
at test pressure may be tested as follows:
    (i) At least one cylinder selected at random out of each lot of 200 
or less must be tested in accordance with paragraphs (h)(1), (h)(2), and 
(h)(3) of this section.
    (ii) All cylinders not tested as provided in paragraph (h)(4)(i) of 
this section must be examined under pressure of at least 2 times service 
pressure and show no defect.
    (5) One finished cylinder selected at random out of each lot of 
1,000 or less must be hydrostatically tested to 4 times the service 
pressure without bursting. Inability to meet this requirement must 
result in rejection of the lot.
    (i) Flattening test. After hydrostatic testing, a flattening test is 
required on one section of a cylinder, taken at random out of each lot 
of 200 or less as follows:
    (1) If the weld is not at midlength of the cylinder, the test 
section must be no less in width than 30 times the cylinder wall 
thickness. The weld must be in the center of the section. Weld 
reinforcement must be removed by machining or grinding so that the weld 
is flush with the exterior of the parent metal. There must be no 
evidence of cracking in the sample when it is flattened between flat 
plates to no more than 6 times the wall thickness.
    (2) Guided bend test. A bend test specimen must be cut from the 
cylinder used for the physical test specified in paragraph (j) of this 
section. Specimen must be taken across the seam, must be a minimum of 
1\1/2\ inches wide, edges must be parallel and rounded with a file, and 
back-up strip, if used, must be removed by machining. The specimen shall 
be tested as follows:
    (i) The specimen must be bent to refusal in the guided bend test jig 
as illustrated in paragraph 6.10 of CGA C-3 (IBR, see Sec. 171.7 of 
this subchapter). The root of the weld (inside surface of the cylinder) 
must be located away from the ram of the jig. The specimen must not show 
a crack or other open defect exceeding \1/8\ inch in any direction upon 
completion of the test. Should this specimen fail to meet the 
requirements, specimens may be taken from each of 2 additional cylinders 
from the same lot and tested. If either of the latter specimens fails to 
meet requirements, the entire lot represented must be rejected.
    (ii) Alternatively, the specimen may be tested in a guided bend test 
jig as illustrated in Figure 12.1 of The Aluminum Association's 2002 
publication, ``Welding Aluminum: Theory and Practice.'' The root of the 
weld (inside surface of the cylinder) must be located away from the 
mandrel of the jig. No specimen must show a crack or other open defect 
exceeding \1/8\ inch in any direction upon completion of the test. 
Should this specimen fail to meet the requirements, specimens may be 
taken from each of 2 additional cylinders from the same lot and tested. 
If either of the latter specimens fails to meet requirements, the entire 
lot represented must be rejected.
    (j) Physical test. A physical test must be conducted to determine 
yield strength, tensile strength, elongation, and reduction of area of 
material as follows:
    (1) The test is required on 2 specimens cut from one cylinder or 
part thereof taken at random out of each lot of 200 or less.
    (2) Specimens must conform to the following:
    (i) A gauge length of 8 inches with a width not over 1\1/2\ inches, 
a gauge length of 2 inches with a width not over 1\1/2\ inches.
    (ii) The specimen, exclusive of grip ends, may not be flattened. 
Grip ends may be flattened to within 1 inch of each end of the reduced 
section.
    (iii) When size of cylinder does not permit securing straight 
specimens, the specimens may be taken in any location or direction and 
may be

[[Page 81]]

straightened or flattened cold, by pressure only, not by blows; when 
specimens are so taken and prepared, the inspector's report must show in 
connection with record of physical test detailed information in regard 
to such specimens.
    (iv) Heating of a specimen for any purpose is not authorized.
    (3) The yield strength in tension must be the stress corresponding 
to a permanent strain of 0.2 percent of the gauge length. The following 
conditions apply:
    (i) The yield strength must be determined by the ``offset'' method 
as prescribed in ASTM E 8 (IBR, see Sec. 171.7 of this subchapter).
    (ii) Cross-head speed of the testing machine may not exceed \1/8\ 
inch per minute during yield strength determination.
    (k) Acceptable results for physical tests. An acceptable result of 
the physical test requires an elongation to at least 7 percent and yield 
strength not over 80 percent of tensile strength.
    (l) Weld tests. Welds of the cylinder are required to successfully 
pass the following tests:
    (1) Reduced section tensile test. A specimen must be cut from the 
cylinder used for the physical tests specified in paragraph (j) of this 
section. The specimen must be taken from across the seam, edges must be 
parallel for a distance of approximately 2 inches on either side of the 
weld. The specimen must be fractured in tension. The apparent breaking 
stress calculated on the minimum wall thickness must be at least equal 
to 2 times the stress calculated under paragraph (f)(2) of this section, 
and in addition must have an actual breaking stress of at least 30,000 
psi. Should this specimen fail to meet the requirements, specimens may 
be taken from 2 additional cylinders from the same lot and tested. If 
either of the latter specimens fails to meet requirements, the entire 
lot represented must be rejected.
    (2) Guided bend test. A bend test specimen must be cut from the 
cylinder used for the physical tests specified in paragraph (j) of this 
section. Specimen must be taken across the seam, must be 1\1/2\ inches 
wide, edges must be parallel and rounded with a file, and back-up strip, 
if used, must be removed by machining. The specimen must be bent to 
refusal in the guided bend test jig illustrated in paragraph 6.10 of CGA 
Pamphlet C-3 (IBR, see Sec. 171.7 of this subchapter). The root of the 
weld (inside surface of the cylinder) must be located away from the ram 
of the jig. No specimen must show a crack or other open defect exceeding 
\1/8\ inch in any direction upon completion of the test. Should this 
specimen fail to meet the requirements, specimens may be taken from each 
of 2 additional cylinders from the same lot and tested. If either of the 
latter specimens fail to meet requirements, the entire lot represented 
must be rejected.
    (m) Rejected cylinders. Repair of welded seams is authorized. 
Acceptable cylinders must pass all prescribed tests.
    (n) Inspector's report. In addition to the information required by 
Sec. 178.35, the record of chemical analyses must also include 
applicable information on iron, titanium, zinc, and magnesium used in 
the construction of the cylinder.

[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 62 FR 51561, 
Oct. 1, 1997; 66 FR 45386, Aug. 28, 2001; 67 FR 51654, Aug. 8, 2002; 68 
FR 75748, Dec. 31, 2003; 69 FR 54046, Sept. 7, 2004; 74 FR 16143, Apr. 
9, 2009]



Sec. 178.69  Responsibilities and requirements for manufacturers of
UN pressure receptacles.

    (a) Each manufacturer of a UN pressure receptacle marked with 
``USA'' as a country of approval must comply with the requirements in 
this section. The manufacturer must maintain a quality system, obtain an 
approval for each initial pressure receptacle design type, and ensure 
that all production of UN pressure receptacles meets the applicable 
requirements.
    (1) Quality system. The manufacturer of a UN pressure receptacle 
must have its quality system approved by the Associate Administrator. 
The quality system will initially be assessed through an audit by the 
Associate Administrator or his or her representative to determine 
whether it meets the requirements of this section. The Associate 
Administrator will notify the manufacturer in writing of the results of 
the audit. The notification will contain the conclusions of the audit 
and

[[Page 82]]

any corrective action required. The Associate Administrator may perform 
periodic audits to ensure that the manufacturer operates in accordance 
with the quality system. Reports of periodic audits will be provided to 
the manufacturer. The manufacturer must bear the cost of audits.
    (2) Quality system documentation. The manufacturer must be able to 
demonstrate a documented quality system. Management must review the 
adequacy of the quality system to assure that it is effective and 
conforms to the requirements in Sec. 178.70. The quality system records 
must be in English and must include detailed descriptions of the 
following:
    (i) The organizational structure and responsibilities of personnel 
with regard to design and product quality;
    (ii) The design control and design verification techniques, 
processes, and procedures used when designing the pressure receptacles;
    (iii) The relevant procedures for pressure receptacle manufacturing, 
quality control, quality assurance, and process operation instructions;
    (iv) Inspection and testing methodologies, measuring and testing 
equipment, and calibration data;
    (v) The process for meeting customer requirements;
    (vi) The process for document control and document revision;
    (vii) The system for controlling non-conforming material and 
records, including procedures for identification, segregation, and 
disposition;
    (viii) Production, processing and fabrication, including purchased 
components, in-process and final materials; and
    (ix) Training programs for relevant personnel.
    (3) Maintenance of quality system. The manufacturer must maintain 
the quality system as approved by the Associate Administrator. The 
manufacturer shall notify the Associate Administrator of any intended 
changes to the approved quality system prior to making the change. The 
Associate Administrator will evaluate the proposed change to determine 
whether the amended quality system will satisfy the requirements. The 
Associate Administrator will notify the manufacturer of the findings.
    (b) Design type approvals. The manufacturer must have each pressure 
receptacle design type reviewed by an IIA and approved by the Associate 
Administrator in accordance with Sec. 178.70. A cylinder is considered 
to be of a new design, compared with an existing approved design, as 
stated in the applicable ISO design, construction and testing standard.
    (c) Production inspection and certification. The manufacturer must 
ensure that each UN pressure receptacle is inspected and certified in 
accordance with Sec. 178.71.

[71 FR 33885, June 12, 2006]



Sec. 178.70  Approval of UN pressure receptacles.

    (a) Initial design-type approval. The manufacturer of a UN pressure 
receptacle must obtain an initial design type approval from the 
Associate Administrator. The initial design type approval must be of the 
pressure receptacle design as it is intended to be produced. The 
manufacturer must arrange for an IIA, approved by the Associate 
Administrator in accordance with subpart I of part 107 of this chapter, 
to perform a pre-audit of its pressure receptacle manufacturing 
operation prior to having an audit conducted by the Associate 
Administrator or his designee.
    (b) IIA pre-audit. The manufacturer must submit an application for 
initial design type approval to the IIA for review. The IIA will examine 
the manufacturer's application for initial design type approval for 
completeness. An incomplete application will be returned to the 
manufacturer with an explanation. If an application is complete, the IIA 
will review all technical documentation, including drawings and 
calculations, to verify that the design meets all requirements of the 
applicable UN pressure receptacle standard and specification 
requirements. If the technical documentation shows that the pressure 
receptacle prototype design conforms to the applicable standards and 
requirements in Sec. 178.70, the

[[Page 83]]

manufacturer will fabricate a prototype lot of pressure receptacles in 
conformance with the technical documentation representative of the 
design. The IIA will verify that the prototype lot conforms to the 
applicable requirements by selecting pressure receptacles and witnessing 
their testing. After prototype testing has been satisfactorily 
completed, showing the pressure receptacles fully conform to all 
applicable specification requirements, the certifying IIA must prepare a 
letter of recommendation and a design type approval certificate. The 
design type approval certificate must contain the name and address of 
the manufacturer and the IIA certifying the design type, the test 
results, chemical analyses, lot identification, and all other supporting 
data specified in the applicable ISO design, construction and testing 
standard. The IIA must provide the certificate and documentation to the 
manufacturer.
    (c) Application for initial design type approval. If the pre-audit 
is found satisfactory by the IIA, the manufacturer will submit the 
letter of recommendation from the IIA and an application for design type 
approval to the Associate Administrator. An application for initial 
design type approval must be submitted for each manufacturing facility. 
The application must be in English and, at a minimum, contain the 
following information:
    (1) The name and address of the manufacturing facility. If the 
application is submitted by an authorized representative on behalf of 
the manufacturer, the application must include the representative's name 
and address.
    (2) The name and title of the individual responsible for the 
manufacturer's quality system, as required by Sec. 178.69.
    (3) The designation of the pressure receptacle and the relevant 
pressure receptacle standard.
    (4) Details of any refusal of approval of a similar application by a 
designated approval agency of another country.
    (5) The name and address of the production IIA that will perform the 
functions prescribed in paragraph (e) of this section. The IIA must be 
approved in writing by the Associate Administrator in accordance with 
subpart I of part 107 of this chapter.
    (6) Documentation on the manufacturing facility as specified in 
Sec. 178.69.
    (7) Design specifications and manufacturing drawings, showing 
components and subassemblies if relevant, design calculations, and 
material specifications necessary to verify compliance with the 
applicable pressure receptacle design standard.
    (8) Manufacturing procedures and any applicable standards that 
describe in detail the manufacturing processes and control.
    (9) Design type approval test reports detailing the results of 
examinations and tests conducted in accordance with the relevant 
pressure receptacle standard, to include any additional data, such as 
suitability for underwater applications or compatibility with hydrogen 
embrittlement gases.
    (d) Modification of approved pressure receptacle design type. 
Modification of an approved UN pressure receptacle design type is not 
authorized without the approval of the Associate Administrator. A 
manufacturer seeking modification of an approved UN pressure receptacle 
design type may be required to submit design qualification test data to 
the Associate Administrator before production. An audit may be required 
as part of the process to modify an approval.
    (e) Responsibilities of the production IIA. The production IIA is 
responsible for ensuring that each pressure receptacle conforms to the 
design type approval. The production IIA must perform the following 
functions:
    (1) Witness all inspections and tests specified in the UN pressure 
receptacle standard to ensure compliance with the standard and that the 
procedures adopted by the manufacturer meet the requirements of the 
standard;
    (2) Verify that the production inspections were performed in 
accordance with this section;
    (3) Select UN pressure receptacles from a prototype production lot 
and witness testing as required for the design type approval;
    (4) Ensure that the various design type approval examinations and 
tests are performed accurately;

[[Page 84]]

    (5) Verify that each pressure receptacle is marked in accordance 
with the applicable requirements in Sec. 178.72; and
    (6) Furnish complete test reports to the manufacturer and upon 
request to the purchaser. The test reports and certificate of compliance 
must be retained by the IIA for at least 20 years from the original test 
date of the pressure receptacles.
    (f) Production inspection audit and certification. (1) If the 
application, design drawing and quality control documents are found 
satisfactory, PHMSA will schedule an on-site audit of the pressure 
receptacle manufacturer's quality system, manufacturing processes, 
inspections, and test procedures.
    (2) During the audit, the manufacturer will be required to produce 
pressure receptacles to the technical standards for which approval is 
sought.
    (3) The production IIA must witness the required inspections and 
verifications on the pressure receptacles during the production run. The 
IIA selected by the manufacturer for production inspection and testing 
may be different from the IIA who performed the design type approval 
verifications.
    (4) If the procedures and controls are deemed acceptable, test 
sample pressure receptacles will be selected at random from the 
production lot and sent to a laboratory designated by the Associate 
Administrator for verification testing.
    (5) If the pressure receptacle test samples are found to conform to 
all the applicable requirements, the Associate Administrator will issue 
approvals to the manufacturer and the production IIA to authorize the 
manufacture of the pressure receptacles. The approved design type 
approval certificate will be returned to the manufacturer.
    (6) Upon the receipt of the approved design type approval 
certificate from the Associate Administrator, the pressure receptacle 
manufacturer must sign the certificate.
    (g) Recordkeeping. The production IIA and the manufacturer must 
retain a copy of the design type approval certificate and certificate of 
compliance records for at least 20 years.
    (h) Denial of design type application. If the design type 
application is denied, the Associate Administrator will notify the 
applicant in writing and provide the reason for the denial. The 
manufacturer may request that the Associate Administrator reconsider the 
decision. The application request must--
    (1) Be written in English and filed within 60 days of receipt of the 
decision;
    (2) State in detail any alleged errors of fact and law; and
    (3) Enclose any additional information needed to support the request 
to reconsider.
    (i) Appeal. (1) A manufacturer whose reconsideration request is 
denied may appeal to the PHMSA Administrator. The appeal must--
    (i) Be written in English and filed within 60 days of receipt of the 
Associate Administrator's decision on reconsideration;
    (ii) State in detail any alleged errors of fact and law;
    (iii) Enclose any additional information needed to support the 
appeal; and
    (iv) State in detail the modification of the final decision sought.
    (2) The PHMSA Administrator will grant or deny the relief and inform 
the appellant in writing of the decision. PHMSA Administrator's decision 
is the final administrative action.
    (j) Termination of a design type approval certificate. (1) The 
Associate Administrator may terminate an approval certificate issue 
under this section if it is determined that, because of a change in 
circumstances, the approval no longer is needed or no longer would be 
granted if applied for; information upon which the approval was based is 
fraudulent or substantially erroneous; or termination of the approval is 
necessary to adequately protect against risks to life and property.
    (2) Before an approval is terminated, the Associate Administrator 
will provide the manufacturer and the approval agency--
    (i) Written notice of the facts or conduct believed to warrant the 
withdrawal;
    (ii) Opportunity to submit oral and written evidence, and
    (iii) Opportunity to demonstrate or achieve compliance with the 
application requirement.

[[Page 85]]

    (3) If the Associate Administrator determines that a certificate of 
approval must be withdrawn to preclude a significant and imminent 
adverse affect on public safety, the procedures in paragraph (j)(2)(ii) 
and (iii) of this section need not be provided prior to withdrawal of 
the approval, but shall be provided as soon as practicable thereafter.

[71 FR 33886, June 12, 2006, as amended at 71 FR 54397, Sept. 14, 2006]



Sec. 178.71  Specifications for UN pressure receptacles.

    (a) General. Each UN pressure receptacle must meet the requirements 
of this section. Requirements for approval, qualification, maintenance, 
and testing are contained in Sec. 178.70, and subpart C of part 180 of 
this subchapter.
    (b) Definitions. The following definitions apply for the purposes of 
design and construction of UN pressure receptacles under this subpart:
    Alternative arrangement means an approval granted by the Associate 
Administrator for a MEGC that has been designed, constructed or tested 
to the technical requirements or testing methods other than those 
specified for UN pressure receptacles in part 178 or part 180 of this 
subchapter.
    Bundle of cylinders. See Sec. 171.8 of this subchapter.
    Design type means a pressure receptacle design as specified by a 
particular pressure receptacle standard.
    Design type approval means an overall approval of the manufacturer's 
quality system and design type of each pressure receptacle to be 
produced within the manufacturer's facility.
    UN tube. See Sec. 171.8 of this subchapter.
    (c) Following the final heat treatment, all cylinders, except those 
selected for batch testing must be subjected to a proof pressure or a 
hydraulic volumetric expansion test.
    (d) Service equipment. (1) Except for pressure relief devices, UN 
pressure receptacle equipment, including valves, piping, fittings, and 
other equipment subjected to pressure must be designed and constructed 
to withstand at least 1.5 times the test pressure of the pressure 
receptacle.
    (2) Service equipment must be configured or designed to prevent 
damage that could result in the release of the pressure receptacle 
contents during normal conditions of handling and transport. Manifold 
piping leading to shut-off valves must be sufficiently flexible to 
protect the valves and the piping from shearing or releasing the 
pressure receptacle contents. The filling and discharge valves and any 
protective caps must be secured against unintended opening. The valves 
must conform to ISO 10297 (IBR, see Sec. 171.7 of this subchapter) and 
be protected as specified in Sec. 173.301b(f) of this subchapter.
    (3) UN pressure receptacles that cannot be handled manually or 
rolled, must be equipped with devices (e.g., skids, rings, straps) 
ensuring that they can be safely handled by mechanical means and so 
arranged as not to impair the strength of, nor cause undue stresses, in 
the pressure receptacle.
    (4) Pressure receptacles filled by volume must be equipped with a 
level indicator.
    (e) Bundles of cylinders. UN pressure receptacles assembled in 
bundles must be structurally supported and held together as a unit and 
secured in a manner that prevents movement in relation to the structural 
assembly and movement that would result in the concentration of harmful 
local stresses. The frame design must ensure stability under normal 
operating conditions.
    (1) The frame must securely retain all the components of the bundle 
and must protect them from damage during conditions normally incident to 
transportation. The method of cylinder restraint must prevent any 
vertical or horizontal movement or rotation of the cylinder that could 
cause undue strain on the manifold. The total assembly must be able to 
withstand rough handling, including being dropped or overturned.
    (2) The frame must include features designed for the handling and 
transportation of the bundle. The lifting rings must be designed to 
withstand a design load of 2 times the maximum gross weight. Bundles 
with more than one lifting ring must be designed such that a minimum 
sling angle of 45 degrees to the horizontal can be achieved during 
lifting using the lifting rings. If four

[[Page 86]]

lifting rings are used, their design must be strong enough to allow the 
bundle to be lifted by two rings. Where two or four lifting rings are 
used, diametrically opposite lifting rings must be aligned with each 
other to allow for correct lifting using shackle pins. If the bundle is 
filled with forklift pockets, it must contain two forklift pockets on 
each side from which it is to be lifted. The forklift pockets must be 
positioned symmetrically consistent with the bundle center of gravity.
    (3) The frame structural members must be designed for a vertical 
load of 2 times the maximum gross weight of the bundle. Design stress 
levels may not exceed 0.9 times the yield strength of the material.
    (4) The frame must not contain any protrusions from the exterior 
frame structure that could cause a hazardous condition.
    (5) The frame design must prevent collection of water or other 
debris that would increase the tare weight of bundles filled by weight.
    (6) The floor of the bundle frame must not buckle during normal 
operating conditions and must allow for the drainage of water and debris 
from around the base of the cylinders.
    (7) If the frame design includes movable doors or covers, they must 
be capable of being secured with latches or other means that will not 
become dislodged by operational impact loads. Valves that need to be 
operated in normal service or in an emergency must be accessible.
    (8) For bundles of cylinders, pressure receptacle marking 
requirements only apply to the individual cylinders of a bundle and not 
to any assembly structure.
    (f) Design and construction requirements for UN refillable welded 
cylinders. In addition to the general requirements of this section, UN 
refillable welded cylinders must conform to the following ISO standards, 
as applicable:
    (1) ISO 4706: Gas cylinders--Refillable welded steel cylinders--Test 
pressure 60 bar and below (IBR, see Sec. 171.7 of this subchapter).
    (2) ISO 18172-1: Gas cylinders--Refillable welded stainless steel 
cylinders--Part 1: Test pressure 6 MPa and below (IBR, see Sec. 171.7 
of this subchapter).
    (3) ISO 20703: Gas cylinders--Refillable welded aluminum-alloy 
cylinders--Design, construction and testing (IBR, see Sec. 171.7 of 
this subchapter).
    (g) Design and construction requirements for UN refillable seamless 
steel cylinders. In addition to the general requirements of this 
section, UN refillable seamless steel cylinders must conform to the 
following ISO standards, as applicable:
    (1) ISO 9809-1: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1 100 MPa. 
(IBR, see Sec. 171.7 of this subchapter).
    (2) ISO 9809-2: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 2: Quenched and 
tempered steel cylinders with tensile strength greater than or equal to 
1 100 MPa. (IBR, see Sec. 171.7 of this subchapter).
    (3) ISO 9809-3: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 3: Normalized steel 
cylinders. (IBR, see Sec. 171.7 of this subchapter).
    (h) Design and construction requirements for UN refillable seamless 
aluminum alloy cylinders. In addition to the general requirements of 
this section, UN refillable seamless aluminum cylinders must conform to 
ISO 7866: Gas cylinders--Refillable seamless aluminum alloy gas 
cylinders--Design, construction and testing. (IBR, see Sec. 171.7 of 
this subchapter). The use of Aluminum alloy 6351-T6 or equivalent is 
prohibited.
    (i) Design and construction requirements for UN non-refillable metal 
cylinders. In addition to the general requirements of this section, UN 
non-refillable metal cylinders must conform to ISO 11118: Gas 
cylinders--Non-refillable metallic gas cylinders--Specification and test 
methods. (IBR, see Sec. 171.7 of this subchapter.)
    (j) Design and construction requirements for UN refillable seamless 
steel tubes. In addition to the general requirements of this section, UN 
refillable seamless steel tubes must conform to ISO 11120: Gas 
cylinders--Refillable seamless steel tubes of water capacity

[[Page 87]]

between 150 L and 3000 L--Design, construction and testing. (IBR, see 
Sec. 171.7 of this subchapter).
    (k) Design and construction requirements for UN acetylene cylinders. 
In addition to the general requirements of this section, UN acetylene 
cylinders must conform to the following ISO standards, as applicable:
    (1) For the cylinder shell:
    (i) ISO 9809-1: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1 100 MPa.
    (ii) ISO 9809-3: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 3: Normalized steel 
cylinders.
    (2) The porous mass in an acetylene cylinder must conform to ISO 
3807-2: Cylinders for acetylene--Basic requirements--Part 2: Cylinders 
with fusible plugs. (IBR, see Sec. 171.7 of this subchapter).
    (l) Design and construction requirements for UN composite cylinders. 
(1) In addition to the general requirements of this section, UN 
composite cylinders must be designed for unlimited service life and 
conform to the following ISO standards, as applicable:
    (i) ISO 11119-1: Gas cylinders of composite construction--
Specification and test methods--Part 1: Hoop-wrapped composite gas 
cylinders. (IBR, see Sec. 171.7 of this subchapter).
    (ii) ISO 11119-2: Gas cylinders of composite construction--
Specification and test methods--Part 2: Fully-wrapped fibre reinforced 
composite gas cylinders with load-sharing metal liners. (IBR, see Sec. 
171.7 of this subchapter).
    (iii) ISO 11119-3: Gas cylinders of composite construction--
Specification and test methods--Part 3: Fully wrapped fibre reinforced 
composite gas cylinders with non-load sharing metallic or non-metallic 
liners. (IBR, see Sec. 171.7 of this subchapter).
    (2) ISO 11119-2 and ISO 11119-3 gas cylinders of composite 
construction manufactured in accordance with the requirements for 
underwater use must bear the ``UW'' mark.
    (m) Design and construction requirements for UN metal hydride 
storage systems. In addition to the general requirements of this 
section, metal hydride storage systems must conform to the following ISO 
standards, as applicable: ISO 16111: Transportable gas storage devices--
Hydrogen absorbed in reversible metal hydride (IBR, see Sec. 171.7 of 
this subchapter).
    (n) Material compatibility. In addition to the material requirements 
specified in the UN pressure receptacle design and construction ISO 
standards, and any restrictions specified in part 173 for the gases to 
be transported, the requirements of the following standards must be 
applied with respect to material compatibility:
    (1) ISO 11114-1: Transportable gas cylinders--Compatibility of 
cylinder and valve materials with gas contents--Part 1: Metallic 
materials. (IBR, see Sec. 171.7 of this subchapter).
    (2) ISO 11114-2: Transportable gas cylinders--Compatibility of 
cylinder and valve materials with gas contents--Part 2: Non-metallic 
materials. (IBR, see Sec. 171.7 of this subchapter).
    (o) Protection of closures. Closures and their protection must 
conform to the requirements in Sec. 173.301(f) of this subchapter.
    (p) Marking of UN refillable pressure receptacles. UN refillable 
pressure receptacles must be marked clearly and legibly. The required 
markings must be permanently affixed by stamping, engraving, or other 
equivalent method, on the shoulder, top end or neck of the pressure 
receptacle or on a permanently affixed component of the pressure 
receptacle, such as a welded collar. Except for the ``UN'' mark, the 
minimum size of the marks must be 5 mm for pressure receptacles with a 
diameter greater than or equal to 140 mm, and 2.5 mm for pressure 
receptacles with a diameter less than 140 mm. The minimum size of the 
``UN'' mark must be 5 mm for pressure receptacles with a diameter less 
than 140 mm, and 10 mm for pressure receptacles with a diameter of 
greater than or equal to 140 mm. The depth of the markings must not 
create harmful stress concentrations. A refillable pressure receptacle 
conforming to the UN standard must be marked as follows:
    (1) The UN packaging symbol.

[[Page 88]]

[GRAPHIC] [TIFF OMITTED] TR19JA11.035

    (2) The ISO standard, for example ISO 9809-1, used for design, 
construction and testing. Acetylene cylinders must be marked to indicate 
the porous mass and the steel shell, for example: ``ISO 3807-2/ISO 9809-
1.''
    (3) The mark of the country where the approval is granted. The 
letters ``USA'' must be marked on UN pressure receptacles approved by 
the United States. The manufacturer must obtain an approval number from 
the Associate Administrator. The manufacturer approval number must 
follow the country of approval mark, separated by a slash (for example, 
USA/MXXXX). Pressure receptacles approved by more than one national 
authority may contain the mark of each country of approval, separated by 
a comma.
    (4) The identity mark or stamp of the IIA.
    (5) The date of the initial inspection, the year (four digits) 
followed by the month (two digits) separated by a slash, for example 
``2006/04''.
    (6) The test pressure in bar, preceded by the letters ``PH'' and 
followed by the letters ``BAR''.
    (7) The rated charging pressure of the metal hydride storage system 
in bar, preceded by the letters ``RCP'' and followed by the letters 
``BAR.''
    (8) The empty or tare weight. Except for acetylene cylinders, empty 
weight is the mass of the pressure receptacle in kilograms, including 
all integral parts (e.g., collar, neck ring, foot ring, etc.), followed 
by the letters ``KG''. The empty weight does not include the mass of the 
valve, valve cap or valve guard or any coating. The empty weight must be 
expressed to three significant figures rounded up to the last digit. For 
cylinders of less than 1 kg, the empty weight must be expressed to two 
significant figures rounded down to the last digit. For acetylene 
cylinders, the tare weight must be marked on the cylinders in kilograms. 
The tare weight is the sum of the empty weight, mass of the valve, any 
coating and all permanently attached parts (e.g., fittings and 
accessories) that are not removed during filling. The tare weight must 
be expressed to two significant figures rounded down to the last digit. 
The tare weight does not include the cylinder cap or any outlet cap or 
plug not permanently attached to the cylinder.
    (9) The minimum wall thickness of the pressure receptacle in 
millimeters followed by the letters ``MM''. This mark is not required 
for pressure receptacles with a water capacity less than or equal to 1.0 
L or for composite cylinders.
    (10) For pressure receptacles intended for the transport of 
compressed gases and UN 1001 acetylene, dissolved, the working pressure 
in bar, proceeded by the letters ``PW''.
    (11) For liquefied gases, the water capacity in liters expressed to 
three significant digits rounded down to the last digit, followed by the 
letter ``L''. If the value of the minimum or nominal water capacity is 
an integer, the digits after the decimal point may be omitted.
    (12) Identification of the cylinder thread type (e.g., 25E).
    (13) The country of manufacture. The letters ``USA'' must be marked 
on cylinders manufactured in the United States.
    (14) The serial number assigned by the manufacturer.
    (15) For steel pressure receptacles, the letter ``H'' showing 
compatibility of the steel, as specified in 1SO 11114-1.

[[Page 89]]

    (16) Identification of aluminum alloy, if applicable.
    (17) Stamp for nondestructive testing, if applicable.
    (18) Stamp for underwater use of composite cylinders, if applicable.
    (19) For metal hydride storage systems having a limited life, the 
date of expiration indicated by the word ``FINAL,'' followed by the year 
(four digits), the month (two digits) and separated by a slash.
    (q) Marking sequence. The marking required by paragraph (p) of this 
section must be placed in three groups as shown in the example below:
    (1) The top grouping contains manufacturing marks and must appear 
consecutively in the sequence given in paragraphs (p)(13) through (19) 
of this section.
    (2) The middle grouping contains operational marks described in 
paragraphs (p)(6) through (11) of this section.
    (3) The bottom grouping contains certification marks and must appear 
consecutively in the sequence given in paragraphs (p)(1) through (5) of 
this section.

[[Page 90]]

[GRAPHIC] [TIFF OMITTED] TR19JA11.036

    (r) Other markings. Other markings are allowed in areas other than 
the side wall, provided they are made in low stress areas and are not of 
a size and depth that will create harmful stress concentrations. Such 
marks must not conflict with required marks.

[[Page 91]]

    (s) Marking of UN non-refillable pressure receptacles. Unless 
otherwise specified in this paragraph, each UN non-refillable pressure 
receptacle must be clearly and legibly marked as prescribed in paragraph 
(p) of this section. In addition, permanent stenciling is authorized. 
Except when stenciled, the marks must be on the shoulder, top end or 
neck of the pressure receptacle or on a permanently affixed component of 
the pressure receptacle (e.g., a welded collar).
    (1) The marking requirements and sequence listed in paragraphs 
(p)(1) through (19) of this section are required, except the markings in 
paragraphs (p)(8), (9), (12) and (18) are not applicable. The required 
serial number marking in paragraph (p)(14) may be replaced by the batch 
number.
    (2) Each receptacle must be marked with the words ``DO NOT REFILL'' 
in letters of at least 5 mm in height.
    (3) A non-refillable pressure receptacle, because of its size, may 
substitute the marking required by this paragraph with a label. 
Reduction in marking size is authorized only as prescribed in ISO 7225, 
Gas cylinders--Precautionary labels. (IBR, see Sec. 171.7 of this 
subchapter).
    (4) Each non-refillable pressure receptacle must also be legibly 
marked by stenciling the following statement: ``Federal law forbids 
transportation if refilled-penalty up to $500,000 fine and 5 years in 
imprisonment (49 U.S.C. 5124).''
    (5) No person may mark a non-refillable pressure receptacle as 
meeting the requirements of this section unless it was manufactured in 
conformance with this section.

[76 FR 3385, Jan. 19, 2011, as amended at 76 FR 43532, July 20, 2011]



Sec. 178.74  Approval of MEGCs.

    (a) Application for design type approval. (1) Each new MEGC design 
type must have a design approval certificate. An owner or manufacturer 
must apply to an approval agency that is approved by the Associate 
Administrator in accordance with subpart E of part 107 of this chapter 
+to obtain approval of a new design. When a series of MEGCs is 
manufactured without change in the design, the certificate is valid for 
the entire series. The design approval certificate must refer to the 
prototype test report, the materials of construction of the manifold, 
the standards to which the pressure receptacles are made and an approval 
number. The compliance requirements or test methods applicable to MEGCs 
as specified in this subpart may be varied when the level of safety is 
determined to be equivalent to or exceed the requirements of this 
subchapter and is approved in writing by the Associate Administrator. A 
design approval may serve for the approval of smaller MEGCs made of 
materials of the same type and thickness, by the same fabrication 
techniques and with identical supports, equivalent closures and other 
appurtenances.
    (2) Each application for design approval must be in English and 
contain the following information:
    (i) Two complete copies of all engineering drawings, calculations, 
and test data necessary to ensure that the design meets the relevant 
specification.
    (ii) The manufacturer's serial number that will be assigned to each 
MEGC.
    (iii) A statement as to whether the design type has been examined by 
any approval agency previously and judged unacceptable. Affirmative 
statements must be documented with the name of the approval agency, 
reason for non-acceptance, and the nature of modifications made to the 
design type.
    (b) Actions by the approval agency. The approval agency must review 
the application for design type approval, including all drawings and 
calculations, to ensure that the design of the MEGC meets all 
requirements of the relevant specification and to determine whether it 
is complete and conforms to the requirements of this section. An 
incomplete application will be returned to the applicant with the 
reasons why the application was returned. If the application is complete 
and all applicable requirements of this section are met, the approval 
agency must prepare a MEGC design approval certificate containing the 
manufacturer's name and address, results and conclusions of the 
examination and necessary data for identification of the design type. If 
the Associate Administrator approves the

[[Page 92]]

Design Type Approval Certificate application, the approval agency and 
the manufacturer must each maintain a copy of the approved drawings, 
calculations, and test data for at least 20 years.
    (c) Approval agency's responsibilities. The approval agency is 
responsible for ensuring that the MEGC conforms to the design type 
approval. The approval agency must:
    (1) Witness all tests required for the approval of the MEGC 
specified in this section and Sec. 178.75.
    (2) Ensure, through appropriate inspection, that each MEGC is 
fabricated in all respects in conformance with the approved drawings, 
calculations, and test data.
    (3) Determine and ensure that the MEGC is suitable for its intended 
use and that it conforms to the requirements of this subchapter.
    (4) Apply its name, identifying mark or identifying number, and the 
date the approval was issued, to the metal identification marking plate 
attached to the MEGC upon successful completion of all requirements of 
this subpart. Any approvals by the Associate Administrator authorizing 
design or construction alternatives (Alternate Arrangements) of the MEGC 
(see paragraph (a) of this section) must be indicated on the metal 
identification plate as specified in Sec. 178.75(j).
    (5) Prepare an approval certificate for each MEGC or, in the case of 
a series of identical MEGCs manufactured to a single design type, for 
each series of MEGCs. The approval certificate must include all of the 
following information:
    (i) The information displayed on the metal identification plate 
required by Sec. 178.75(j);
    (ii) The results of the applicable framework test specified in ISO 
1496-3 (IBR, see Sec. 171.7 of this subchapter);
    (iii) The results of the initial inspection and test specified in 
paragraph (h) of this section;
    (iv) The results of the impact test specified in Sec. 178.75(i)(4);
    (v) Certification documents verifying that the cylinders and tubes 
conform to the applicable standards; and
    (vi) A statement that the approval agency certifies the MEGC in 
accordance with the procedures in this section and that the MEGC is 
suitable for its intended purpose and meets the requirements of this 
subchapter. When a series of MEGCs is manufactured without change in the 
design type, the certificate may be valid for the entire series of MEGCs 
representing a single design type. The approval number must consist of 
the distinguishing sign or mark of the country (``USA'' for the United 
States of America) where the approval was granted and a registration 
number.
    (6) Retain on file a copy of each approval certificate for at least 
20 years.
    (d) Manufacturers' responsibilities. The manufacturer is responsible 
for compliance with the applicable specifications for the design and 
construction of MEGCs. The manufacturer of a MEGC must:
    (1) Comply with all the requirements of the applicable ISO standard 
specified in Sec. 178.71;
    (2) Obtain and use an approval agency to review the design, 
construction and certification of the MEGC;
    (3) Provide a statement in the manufacturers' data report certifying 
that each MEGC manufactured complies with the relevant specification and 
all the applicable requirements of this subchapter; and
    (4) Retain records for the MEGCs for at least 20 years. When 
required by the specification, the manufacturer must provide copies of 
the records to the approval agency, the owner or lessee of the MEGC, and 
to a representative of DOT, upon request.
    (e) Denial of application for approval. If the Associate 
Administrator finds that the MEGC will not be approved for any reason, 
the Associate Administrator will notify the applicant in writing and 
provide the reason for the denial. The manufacturer may request that the 
Associate Administrator reconsider the decision. The application request 
must--
    (1) Be written in English and filed within 90 days of receipt of the 
decision;
    (2) State in detail any alleged errors of fact and law; and
    (3) Enclose any additional information needed to support the request 
to reconsider.

[[Page 93]]

    (f) Appeal. (1) A manufacturer whose reconsideration request is 
denied may appeal to the PHMSA Administrator. The appeal must--
    (i) Be in writing and filed within 90 days of receipt of the 
Associate Administrator s decision on reconsideration;
    (ii) State in detail any alleged errors of fact and law;
    (iii) Enclose any additional information needed to support the 
appeal; and
    (iv) State in detail the modification of the final decision sought.
    (2) The Administrator will grant or deny the relief and inform the 
appellant in writing of the decision. The Administrator's decision is 
the final administrative action.
    (g) Modifications to approved MEGCs. (1) Prior to modification of 
any approved MEGC that may affect conformance and safe use, and that may 
involve a change to the design type or affect its ability to retain the 
hazardous material in transportation, the MEGC's owner must inform the 
approval agency that prepared the initial approval certificate for the 
MEGC or, if the initial approval agency is unavailable, another approval 
agency, of the nature of the modification and request certification of 
the modification. The owner must supply the approval agency with all 
revised drawings, calculations, and test data relative to the intended 
modification. The MEGC's owner must also provide a statement as to 
whether the intended modification has been examined and determined to be 
unacceptable by any approval agency. The written statement must include 
the name of the approval agency, the reason for non-acceptance, and the 
nature of changes made to the modification since its original rejection.
    (2) The approval agency must review the request for modification. If 
the approval agency determines that the proposed modification does not 
conform to the relevant specification, the approval agency must reject 
the request in accordance with paragraph (d) of this section. If the 
approval agency determines that the proposed modification conforms fully 
with the relevant specification, the request is accepted. If 
modification to an approved MEGC alters any information on the approval 
certificate, the approval agency must prepare a new approval certificate 
for the modified MEGC and submit the certificate to the Associate 
Administrator for approval. After receiving approval from the Associate 
Administrator, the approval agency must ensure that any necessary 
changes are made to the metal identification plate. A copy of each newly 
issued approval certificate must be retained by the approval agency and 
the MEGC's owner for at least 20 years. The approval agency must perform 
the following activities:
    (i) Retain a set of the approved revised drawings, calculations, and 
data as specified in Sec. 178.69(b)(4) for at least 20 years;
    (ii) Ensure through appropriate inspection that all modifications 
conform to the revised drawings, calculations, and test data; and
    (iii) Determine the extent to which retesting of the modified MEGC 
is necessary based on the nature of the proposed modification, and 
ensure that all required retests are satisfactorily performed.
    (h) Termination of Approval Certificate. (1) The Associate 
Administrator may terminate an approval issued under this section if he 
or she determines that--
    (i) Because of a change in circumstances, the approval no longer is 
needed or no longer would be granted if applied for;
    (ii) Information upon which the approval was based is fraudulent or 
substantially erroneous;
    (iii) Termination of the approval is necessary to adequately protect 
against risks to life and property; or
    (iv) The MEGC does not meet the specification.
    (2) Before an approval is terminated, the Associate Administrator 
will provide the person--
    (i) Written notice of the facts or conduct believed to warrant the 
termination;
    (ii) An opportunity to submit oral and written evidence; and
    (3) An opportunity to demonstrate or achieve compliance with the 
applicable requirements.
    (i) Imminent Danger. If the Associate Administrator determines that 
a certificate of approval must be terminated to preclude a significant 
and imminent

[[Page 94]]

adverse effect on public safety, the Associate Administrator may 
terminate the certificate immediately. In such circumstances, the 
opportunities of paragraphs (h)(2) and (3) of this section need not be 
provided prior to termination of the approval, but must be provided as 
soon as practicable thereafter.

[71 FR 33890, June 12, 2006]



Sec. 178.75  Specifications for MEGCs.

    (a) General. Each MEGC must meet the requirements of this section. 
In a MEGC that meets the definition of a ``container'' within the terms 
of the International Convention for Safe Containers (CSC) must meet the 
requirements of the CSC as amended and 49 CFR parts 450 through 453, and 
must have a CSC approval plate.
    (b) Alternate Arrangements. The technical requirements applicable to 
MEGCs may be varied when the level of safety is determined to be 
equivalent to or exceed the requirements of this subchapter. Such an 
alternate arrangement must be approved in writing by the Associate 
Administrator. MEGCs approved to an Alternate Arrangement must be marked 
as required by paragraph (j) of this section.
    (c) Definitions. The following definitions apply:
    Leakproofness test means a test using gas subjecting the pressure 
receptacles and the service equipment of the MEGC to an effective 
internal pressure of not less than 20% of the test pressure.
    Manifold means an assembly of piping and valves connecting the 
filling and/or discharge openings of the pressure receptacles.
    Maximum permissible gross mass or MPGM means the heaviest load 
authorized for transport (sum of the tare mass of the MEGC, service 
equipment and pressure receptacle).
    Service equipment means manifold system (measuring instruments, 
piping and safety devices).
    Shut-off valve means a valve that stops the flow of gas.
    Structural equipment means the reinforcing, fastening, protective 
and stabilizing members external to the pressure receptacles.
    (d) General design and construction requirements. (1) The MEGC must 
be capable of being loaded and discharged without the removal of its 
structural equipment. It must possess stabilizing members external to 
the pressure receptacles to provide structural integrity for handling 
and transport. MEGCs must be designed and constructed with supports to 
provide a secure base during transport and with lifting and tie-down 
attachments that are adequate for lifting the MEGC including when loaded 
to its maximum permissible gross mass. The MEGC must be designed to be 
loaded onto a transport vehicle or vessel and equipped with skids, 
mountings or accessories to facilitate mechanical handling.
    (2) MEGCs must be designed, manufactured and equipped to withstand, 
without loss of contents, all normal handling and transportation 
conditions. The design must take into account the effects of dynamic 
loading and fatigue.
    (3) Each pressure receptacle of a MEGC must be of the same design 
type, seamless steel, and constructed and tested according to one of the 
following ISO standards:
    (i) ISO 9809-1: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1 100 MPa. 
(IBR, see Sec. 171.7 of this subchapter);
    (ii) ISO 9809-2: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 2: Quenched and 
tempered steel cylinders with tensile strength greater than or equal to 
1 100 MPa. (IBR, see Sec. 171.7 of this subchapter);
    (iii) ISO 9809-3: Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 3: Normalized steel 
cylinders. (IBR, see Sec. 171.7 of this subchapter); or
    (iv) ISO 11120: Gas cylinders--Refillable seamless steel tubes of 
water capacity between 150 L and 3000 L--Design, construction and 
testing. (IBR, see Sec. 171.7 of this subchapter).
    (4) Pressure receptacles of MEGCs, fittings, and pipework must be 
constructed of a material that is compatible with the hazardous 
materials intended to be transported, as specified in this subchapter.

[[Page 95]]

    (5) Contact between dissimilar metals that could result in damage by 
galvanic action must be prevented by appropriate means.
    (6) The materials of the MEGC, including any devices, gaskets, and 
accessories, must have no adverse effect on the gases intended for 
transport in the MEGC.
    (7) MEGCs must be designed to withstand, without loss of contents, 
at least the internal pressure due to the contents, and the static, 
dynamic and thermal loads during normal conditions of handling and 
transport. The design must take into account the effects of fatigue, 
caused by repeated application of these loads through the expected life 
of the MEGC.
    (8) MEGCs and their fastenings must, under the maximum permissible 
load, be capable of withstanding the following separately applied static 
forces (for calculation purposes, acceleration due to gravity (g) = 9.81 
m/s\2\):
    (i) In the direction of travel: 2g (twice the MPGM multiplied by the 
acceleration due to gravity);
    (ii) Horizontally at right angles to the direction of travel: 1g 
(the MPGM multiplied by the acceleration due to gravity. When the 
direction of travel is not clearly determined, the forces must be equal 
to twice the MPGM);
    (iii) Vertically upwards: 1g (the MPGM multiplied by the 
acceleration due to gravity); and
    (iv) Vertically downwards: 2g (twice the MPGM (total loading 
including the effect of gravity) multiplied by the acceleration due to 
gravity.
    (9) Under each of the forces specified in paragraph (d)(8) of this 
section, the stress at the most severely stressed point of the pressure 
receptacles must not exceed the values given in the applicable design 
specifications (e.g., ISO 11120).
    (10) Under each of the forces specified in paragraph (d)(8) of this 
section, the safety factor for the framework and fastenings must be as 
follows:
    (i) For steels having a clearly defined yield point, a safety factor 
of 1.5 in relation to the guaranteed yield strength; or
    (ii) For steels with no clearly defined yield point, a safety factor 
of 1.5 in relation to the guaranteed 0.2 percent proof strength and, for 
austenitic steels, the 1 percent proof strength.
    (11) MEGCs must be capable of being electrically grounded to prevent 
electrostatic discharge when intended for flammable gases.
    (12) The pressure receptacles of a MEGC must be secured in a manner 
to prevent movement that could result in damage to the structure and 
concentration of harmful localized stresses.
    (e) Service equipment. (1) Service equipment must be arranged so 
that it is protected from mechanical damage by external forces during 
handling and transportation. When the connections between the frame and 
the pressure receptacles allow relative movement between the 
subassemblies, the equipment must be fastened to allow movement to 
prevent damage to any working part. The manifolds, discharge fittings 
(pipe sockets, shut-off devices), and shut-off valves must be protected 
from damage by external forces. Manifold piping leading to shut-off 
valves must be sufficiently flexible to protect the valves and the 
piping from shearing, or releasing the pressure receptacle contents. The 
filling and discharge devices, including flanges or threaded plugs, and 
any protective caps must be capable of being secured against unintended 
opening.
    (2) Each pressure receptacle intended for the transport of Division 
2.3 gases must be equipped with an individual shut-off valve. The 
manifold for Division 2.3 liquefied gases must be designed so that each 
pressure receptacle can be filled separately and be kept isolated by a 
valve capable of being closed during transit. For Division 2.1 gases, 
the pressure receptacles must be isolated by an individual shut-off 
valve into assemblies of not more than 3,000 L.
    (3) For MEGC filling and discharge openings:
    (i) Two valves in series must be placed in an accessible position on 
each discharge and filling pipe. One of the valves may be a backflow 
prevention valve. (ii) The filling and discharge devices may be equipped 
to a manifold.
    (iii) For sections of piping which can be closed at both ends and 
where a liquid product can be trapped, a pressure-

[[Page 96]]

relief valve must be provided to prevent excessive pressure build-up.
    (iv) The main isolation valves on a MEGC must be clearly marked to 
indicate their directions of closure. All shutoff valves must close by a 
clockwise motion of the handwheel.
    (v) Each shut-off valve or other means of closure must be designed 
and constructed to withstand a pressure equal to or greater than 1.5 
times the test pressure of the MEGC.
    (vi) All shut-off valves with screwed spindles must close by a 
clockwise motion of the handwheel. For other shut-off valves, the open 
and closed positions and the direction of closure must be clearly shown.
    (vii) All shut-off valves must be designed and positioned to prevent 
unintentional opening.
    (viii) Ductile metals must be used in the construction of valves or 
accessories.
    (4) The piping must be designed, constructed and installed to avoid 
damage due to expansion and contraction, mechanical shock and vibration. 
Joints in tubing must be brazed or have an equally strong metal union. 
The melting point of brazing materials must be no lower than 525 [deg]C 
(977 [deg]F). The rated pressure of the service equipment and of the 
manifold must be not less than two-thirds of the test pressure of the 
pressure receptacles.
    (f) Pressure relief devices. Each pressure receptacle must be 
equipped with one or more pressure relief devices as specified in Sec. 
173.301(f) of this subchapter. When pressure relief devices are 
installed, each pressure receptacle or group of pressure receptacles of 
a MEGC that can be isolated must be equipped with one or more pressure 
relief devices. Pressure relief devices must be of a type that will 
resist dynamic forces including liquid surge and must be designed to 
prevent the entry of foreign matter, the leakage of gas and the 
development of any dangerous excess pressure.
    (1) The size of the pressure relief devices: CGA S-1.1 (IBR, see 
Sec. 171.7 of this subchapter) must be used to determine the relief 
capacity of individual pressure receptacles.
    (2) Connections to pressure-relief devices: Connections to pressure 
relief devices must be of sufficient size to enable the required 
discharge to pass unrestricted to the pressure relief device. A shut-off 
valve installed between the pressure receptacle and the pressure relief 
device is prohibited, except where duplicate devices are provided for 
maintenance or other reasons, and the shut-off valves serving the 
devices actually in use are locked open, or the shut-off valves are 
interlocked so that at least one of the duplicate devices is always 
operable and capable of meeting the requirements of paragraph (f)(1) of 
this section. No obstruction is permitted in an opening leading to or 
leaving from a vent or pressure-relief device that might restrict or 
cut-off the flow from the pressure receptacle to that device. The 
opening through all piping and fittings must have at least the same flow 
area as the inlet of the pressure relief device to which it is 
connected. The nominal size of the discharge piping must be at least as 
large as that of the pressure relief device.
    (3) Location of pressure-relief devices: For liquefied gases, each 
pressure relief device must, under maximum filling conditions, be in 
communication with the vapor space of the pressure receptacles. The 
devices, when installed, must be arranged to ensure the escaping vapor 
is discharged upwards and unrestrictedly to prevent impingement of 
escaping gas or liquid upon the MEGC, its pressure receptacles or 
personnel. For flammable, pyrophoric and oxidizing gases, the escaping 
gas must be directed away from the pressure receptacle in such a manner 
that it cannot impinge upon the other pressure receptacles. Heat 
resistant protective devices that deflect the flow of gas are 
permissible provided the required pressure relief device capacity is not 
reduced. Arrangements must be made to prevent access to the pressure 
relief devices by unauthorized persons and to protect the devices from 
damage caused by rollover.
    (g) Gauging devices. When a MEGC is intended to be filled by mass, 
it must be equipped with one or more gauging devices. Glass level-gauges 
and gauges made of other fragile material are prohibited.
    (h) MEGC supports, frameworks, lifting and tie-down attachments. (1) 
MEGCs

[[Page 97]]

must be designed and constructed with a support structure to provide a 
secure base during transport. MEGCs must be protected against damage to 
the pressure receptacles and service equipment resulting from lateral 
and longitudinal impact and overturning. The forces specified in 
paragraph (d)(8) of this section, and the safety factor specified in 
paragraph (d)(10) of this section must be considered in this aspect of 
the design. Skids, frameworks, cradles or other similar structures are 
acceptable. If the pressure receptacles and service equipment are so 
constructed as to withstand impact and overturning, additional 
protective support structure is not required (see paragraph (h)(4) of 
this section).
    (2) The combined stresses caused by pressure receptacle mountings 
(e.g. cradles, frameworks, etc.) and MEGC lifting and tie-down 
attachments must not cause excessive stress in any pressure receptacle. 
Permanent lifting and tie-down attachments must be equipped to all 
MEGCs. Any welding of mountings or attachments onto the pressure 
receptacles is prohibited.
    (3) The effects of environmental corrosion must be taken into 
account in the design of supports and frameworks.
    (4) When MEGCs are not protected during transport as specified in 
paragraph (h)(1) of this section, the pressure receptacles and service 
equipment must be protected against damage resulting from lateral or 
longitudinal impact or overturning. External fittings must be protected 
against release of the pressure receptacles' contents upon impact or 
overturning of the MEGC on its fittings. Particular attention must be 
paid to the protection of the manifold. Examples of protection include:
    (i) Protection against lateral impact, which may consist of 
longitudinal bars;
    (ii) Protection against overturning, which may consist of 
reinforcement rings or bars fixed across the frame;
    (iii) Protection against rear impact, which may consist of a bumper 
or frame;
    (iv) Protection of the pressure receptacles and service equipment 
against damage from impact or overturning by use of an ISO frame 
according to the relevant provisions of ISO 1496-3. (IBR, see Sec. 
171.7 of this subchapter).
    (i) Initial inspection and test. The pressure receptacles and items 
of equipment of each MEGC must be inspected and tested before being put 
into service for the first time (initial inspection and test). This 
initial inspection and test of an MEGC must include the following:
    (1) A check of the design characteristics.
    (2) An external examination of the MEGC and its fittings, taking 
into account the hazardous materials to be transported.
    (3) A pressure test performed at the test pressures specified in 
Sec. 173.304b(b)(1) and (2) of this subchapter. The pressure test of 
the manifold may be performed as a hydraulic test or by using another 
liquid or gas. A leakproofness test and a test of the satisfactory 
operation of all service equipment must also be performed before the 
MEGC is placed into service. When the pressure receptacles and their 
fittings have been pressure-tested separately, they must be subjected to 
a leakproof test after assembly.
    (4) An MEGC that meets the definition of ``container'' in the CSC 
(see 49 CFR 450.3(a)(2)) must be subjected to an impact test using a 
prototype representing each design type. The prototype MEGC must be 
shown to be capable of absorbing the forces resulting from an impact not 
less than 4 times (4 g) the MPGM of the fully loaded MEGC, at a duration 
typical of the mechanical shocks experienced in rail transport. A 
listing of acceptable methods for performing the impact test is provided 
in the UN Recommendations (IBR, see Sec. 171.7 of this subchapter).
    (j) Marking. (1) Each MEGC must be equipped with a corrosion 
resistant metal plate permanently attached to the MEGC in a conspicuous 
place readily accessible for inspection. The pressure receptacles must 
be marked according to this section. Affixing the metal plate to a 
pressure receptacle is prohibited. At a minimum, the following 
information must be marked on the plate by stamping or by any other 
equivalent method:


Country of manufacture

[[Page 98]]

                                   UN
[GRAPHIC] [TIFF OMITTED] TR12JN06.002


Approval Country

Approval Number

Alternate Arrangements (see Sec. 178.75(b))

MEGC Manufacturer's name or mark

MEGC's serial number

Approval agency (Authorized body for the design approval)

Year of manufacture

Test pressure: ------ bar gauge

Design temperature range ------ [deg]C to ------ [deg]C

Number of pressure receptacles ------

Total water capacity ------ liters

Initial pressure test date and identification of the Approval Agency

Date and type of most recent periodic tests

Year ------ Month------ Type ------

(e.g. 2004-05, AE/UE, where ``AE'' represents acoustic emission and 
``UE'' represents ultrasonic examination)

    Stamp of the approval agency who performed or witnessed the most 
recent test
    (2) The following information must be marked on a metal plate firmly 
secured to the MEGC:


Name of the operator

Maximum permissible load mass ------ kg

Working pressure at 15 [deg]C: ------ bar gauge

Maximum permissible gross mass (MPGM) ------ kg

Unladen (tare) mass ------ kg

[71 FR 33892, June 12, 2006, as amended at 73 FR 4719, Jan. 28, 2008]



   Sec. Appendix A to Subpart C of Part 178--Illustrations: Cylinder 
                             Tensile Sample

    The following figures illustrate the recommended locations for test 
specimens taken from welded cylinders:

[[Page 99]]

[GRAPHIC] [TIFF OMITTED] TR08AU02.013


[[Page 100]]


[GRAPHIC] [TIFF OMITTED] TR08AU02.014


[[Page 101]]


[GRAPHIC] [TIFF OMITTED] TR08AU02.015


[[Page 102]]


[GRAPHIC] [TIFF OMITTED] TR08AU02.016


[[Page 103]]


[GRAPHIC] [TIFF OMITTED] TR08AU02.017


[67 FR 51654, Aug. 8, 2002]

[[Page 104]]

Subparts D-G [Reserved]



               Subpart H_Specifications for Portable Tanks

    Source: 29 FR 18972, Dec. 29, 1964, unless otherwise noted. 
Redesignated at 32 FR 5606, Apr. 5, 1967.



Sec. Sec. 178.251--178.253-5  [Reserved]



Sec. 178.255  Specification 60; steel portable tanks.



Sec. 178.255-1  General requirements.

    (a) Tanks must be of fusion welded construction, cylindrical in 
shape with seamless heads concave to the pressure. Tank shells may be of 
seamless construction.
    (b) Tanks must be designed, constructed, certified, and stamped in 
accordance with Section VIII of the ASME Code (IBR, see Sec. 171.7 of 
this subchapter).
    (c) Tanks including all permanent attachments must be postweld heat 
treated as a unit.
    (d) Requirements concerning types of valves, retesting, and 
qualification of portable tanks contained in Sec. Sec. 173.32 and 
173.315 of this chapter must be observed.

[29 FR 18972, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 178-7, 34 FR 18250, Nov. 14, 1969; 68 FR 75750, 
Dec. 31, 2003]



Sec. 178.255-2  Material.

    (a) Material used in the tank must be steel of good weldable quality 
and conform with the requirements in Sections V, VIII, and IX of the 
ASME Code (IBR, see Sec. 171.7 of this subchapter).
    (b) The minimum thickness of metal, exclusive of lining material, 
for shell and heads of tanks shall be as follows:

------------------------------------------------------------------------
                                                                Minimum
                        Tank capacity                          thickness
                                                                (inch)
------------------------------------------------------------------------
Not more than 1,200 gallons.................................       \1/4\
Over 1,200 to 1,800 gallons.................................      \5/16\
Over 1,800 gallons..........................................       \3/8\
------------------------------------------------------------------------


[29 FR 18972, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 178-7, 34 FR 18250, Nov. 14, 1969; 68 FR 75750, 
Dec. 31, 2003]



Sec. 178.255-3  Expansion domes.

    (a) Expansion domes, if applied, must have a minimum capacity of one 
percent of the combined capacity of the tank and dome.
    (b) [Reserved]



Sec. 178.255-4  Closures for manholes and domes.

    (a) The manhole cover shall be designed to provide a secure closure 
of the manhole. All covers, not hinged to the tanks, shall be attached 
to the outside of the dome by at least \1/8\ inch chain or its 
equivalent. Closures shall be made tight against leakage of vapor and 
liquid by use of gaskets of suitable material.
    (b) [Reserved]



Sec. 178.255-5  Bottom discharge outlets.

    (a) Bottom discharge outlets prohibited, except on tanks used for 
shipments of sludge acid and alkaline corrosive liquids.
    (b) If installed, bottom outlets or bottom washout chambers shall be 
of metal not subject to rapid deterioration by the lading, and each 
shall be provided with a valve or plug at its upper end and liquid-tight 
closure at it lower end. Each valve or plug shall be designed to insure 
against unseating due to stresses or shocks incident to transportation. 
Bottom outlets shall be adequately protected against handling damage and 
outlet equipment must not extend to within less than one inch of the 
bottom bearing surface of the skids or tank mounting.

[29 FR 18972, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
as amended by Amdt. 178-104, 59 FR 49135, Sept. 26, 1994]



Sec. 178.255-6  Loading and unloading accessories.

    (a) When installed, gauging, loading and air inlet devices, 
including their valves, shall be provided with adequate means for their 
secure closure; and means shall also be provided for the closing of pipe 
connections of valves.
    (b) Interior heater coils, if installed, must be of extra heavy pipe 
and so constructed that breaking off of exterior connections will not 
cause leakage of tanks.

[[Page 105]]



Sec. 178.255-7  Protection of valves and accessories.

    (a) All valves, fittings, accessories, safety devices, gauging 
devices, and the like shall be adequately protected against mechanical 
damage by a housing closed with a cover plate.
    (b) Protective housing shall comply with the requirements under 
which the tanks are fabricated with respect to design and construction, 
and shall be designed with a minimum factor of safety of four to 
withstand loadings in any direction equal to two times the weight of the 
tank and attachments when filled with water.



Sec. 178.255-8  Safety devices.

    (a) See Sec. 173.315(i) of this subchapter.
    (b) [Reserved]

[Amdt. 178-83, 50 FR 11066, Mar. 19, 1985]



Sec. 178.255-9  Compartments.

    (a) When the interior of the tank is divided into compartments, each 
compartment shall be designed, constructed and tested as a separate 
tank. Thickness of shell and compartment heads shall be determined on 
the basis of total tank capacity.
    (b) [Reserved]



Sec. 178.255-10  Lining.

    (a) If a lining is required, the material used for lining the tank 
shall be homogeneous, nonporous, imperforate when applied, not less 
elastic than the metal of the tank proper. It shall be of substantially 
uniform thickness, not less than \1/32\ inch thick if metallic, and not 
less than \1/16\ inch thick if nonmetallic, and shall be directly bonded 
or attached by other equally satisfactory means. Rubber lining shall be 
not less than \3/16\ inch thick. Joints and seams in the lining shall be 
made by fusing the material together or by other equally satisfactory 
means. The interior of the tank shall be free from scale, oxidation, 
moisture and all foreign matter during the lining operation.
    (b) [Reserved]



Sec. 178.255-11  Tank mountings.

    (a) Tanks shall be designed and fabricated with mountings to provide 
a secure base in transit. ``Skids'' or similar devices shall be deemed 
to comply with this requirement.
    (b) All tank mountings such as skids, fastenings, brackets, cradles, 
lifting lugs, etc., intended to carry loadings shall be permanently 
secured to tanks in accordance with the requirements under which the 
tanks are fabricated, and shall be designed with a factor of safety of 
four, and built to withstand loadings in any direction equal to two 
times the weight of the tanks and attachments when filled to the maximum 
permissible loaded weight.
    (c) Lifting lugs or side hold-down lugs shall be provided on the 
tank mountings in a manner suitable for attaching lifting gear and hold-
down devices. Lifting lugs and hold-down lugs welded directly to the 
tank shall be of the pad-eye type. Doubling plates welded to the tank 
and located at the points of support shall be deemed to comply with this 
requirement.
    (d) All tank mountings shall be so designed as to prevent the 
concentration of excessive loads on the tank shell.



Sec. 178.255-12  Pressure test.

    (a) Each completed portable tank prior to application of lining 
shall be tested before being put into transportation service by 
completely filling the tank with water or other liquid having a similar 
viscosity, the temperature of which shall not exceed 100 [deg]F during 
the test, and applying a pressure of 60 psig. The tank shall be capable 
of holding the prescribed pressure for at least 10 minutes without 
leakage, evidence of impending failure, or failure. All closures shall 
be in place while the test is made and the pressure shall be gauged at 
the top of the tank. Safety devices and/or vents shall be plugged during 
this test.
    (b) [Reserved]

[29 FR 18972, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
as amended by Amdt. 178-104, 59 FR 49135, Sept. 26, 1994]



Sec. 178.255-13  Repair of tanks.

    (a) Tanks failing to meet the test may be repaired and retested, 
provided that repairs are made in complete compliance with the 
requirements of this specification.
    (b) [Reserved]

[[Page 106]]



Sec. 178.255-14  Marking.

    (a) In addition to markings required by Section VIII of the ASME 
Code (IBR, see Sec. 171.7 of this subchapter), every tank shall bear 
permanent marks at least 1/8-inch high stamped into the metal near the 
center of one of the tank heads or stamped into a plate permanently 
attached to the tank by means of brazing or welding or other suitable 
means as follows:

Manufacturer's name -------------- Serial No.___________________________
DOT specification_______________________________________________________
Nominal capacity -------------- (gallons)
Tare weight -------------- (pounds)
Date of manufacture_____________________________________________________

    (b) [Reserved]

[29 FR 18972, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 178-67, 46 FR 49906, Oct. 8, 1981; 68 FR 75750, 
Dec. 31, 2003]



Sec. 178.255-15  Report.

    (a) A copy of the manufacturer's data report required by Section 
VIII of the ASME Code (IBR, see Sec. 171.7 of this subchapter) under 
which the tank is fabricated must be furnished to the owner for each new 
tank.

 Place__________________________________________________________________
 Date___________________________________________________________________
 Portable tank
Manufactured for -------------- Company
Location________________________________________________________________
Manufactured by -------------- Company
Location________________________________________________________________
Consigned to ------------------ Company
Location________________________________________________________________
Size ------ feet outside diameter by ------ long.
Marks on tank as prescribed by Sec. 178.255-14 of this specification 
are as follows:
Manufacturer's name_____________________________________________________
Serial number___________________________________________________________
Owner's serial number___________________________________________________
DOT specification_______________________________________________________
ASME Code Symbol (par U-201)____________________________________________
Date of manufacture_____________________________________________________
Nominal capacity -------------- gallons.
    It is hereby certified that this tank is in complete compliance with 
the requirements of DOT specification No. 60.
 (Signed)_______________________________________________________________
                                                   Manufacturer or owner

    (b) [Reserved]

[29 FR 18972, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 178-83, 50 FR 11066, Mar. 19, 1985; 68 FR 75750, 
Dec. 31, 2003]



Sec. 178.273  Approval of Specification UN portable tanks.

    (a) Application for approval. (1) An owner or manufacturer of a 
portable tank shall apply for approval to a designated approval agency 
authorized to approve the portable tank in accordance with the 
procedures in subpart E, part 107 of this subchapter.
    (2) Each application for approval must contain the following 
information:
    (i) Two complete copies of all engineering drawings, calculations, 
and test data necessary to ensure that the design meets the relevant 
specification.
    (ii) The manufacturer's serial number that will be assigned to each 
portable tank.
    (iii) A statement as to whether the design type has been examined by 
any approval agency previously and judged unacceptable. Affirmative 
statements must be documented with the name of the approval agency, 
reason for nonacceptance, and the nature of modifications made to the 
design type.
    (b) Action by approval agency. The approval agency must perform the 
following activities:
    (1) Review the application for approval to determine whether it is 
complete and conforms with the requirements of paragraph (a) of this 
section. If an application is incomplete, it will be returned to the 
applicant with an explanation as to why the application is incomplete.
    (2) Review all drawings and calculations to ensure that the design 
is in compliance with all requirements of the relevant specification. If 
the application is approved, one set of the approved drawings, 
calculations, and test data shall be returned to the applicant. The 
second (inspector's copy) set of approved drawings, calculations, and 
test data shall be retained by the approval agency. Maintain drawings 
and approval records for as long as the portable tank remains in 
service. The drawings and records must be provided to the Department of 
Transportation (DOT) upon request.
    (3) Witness all tests required for the approval of the portable tank 
specified in this section and part 180, subpart G of this subchapter.

[[Page 107]]

    (4) Ensure, through appropriate inspection that each portable tank 
is fabricated in all respects in conformance with the approved drawings, 
calculations, and test data.
    (5) Determine and ensure that the portable tank is suitable for its 
intended use and that it conforms to the requirements of this 
subchapter.
    (6) For UN portable tanks intended for non-refrigerated and 
refrigerated liquefied gases and Division 6.1 liquids which meet the 
inhalation toxicity criteria (Zone A or B) as defined in Sec. 173.132 
of this subchapter, or that are designated as toxic by inhalation 
materials in the Sec. 172.101 Table of this subchapter, the approval 
agency must ensure that:
    (i) The portable tank has been designed, constructed, certified, and 
stamped in accordance with the requirements in Division 1 of Section 
VIII of the ASME Code (IBR, see Sec. 171.7 of this subchapter). Other 
design codes may be used if approved by the Associate Administrator (see 
Sec. 178.274(b)(1));
    (ii) All applicable provisions of the design and construction have 
been met to the satisfaction of the designated approval agency in 
accordance with the rules established in the ASME Code and that the 
portable tank meets the requirements of the ASME Code and all the 
applicable requirements specified in this subchapter;
    (iii) The inspector has carried out all the inspections specified by 
the rules established in the ASME Code; and
    (iv) The portable tank is marked with a U stamp code symbol under 
the authority of the authorized independent inspector.
    (7) Upon successful completion of all requirements of this subpart, 
the approval agency must:
    (i) Apply its name, identifying mark or identifying number, and the 
date upon which the approval was issued, to the metal identification 
marking plate attached to the portable tank. Any approvals for UN 
portable tanks authorizing design or construction alternatives 
(Alternate Arrangements) approved by the Associate Administrator (see 
Sec. 178.274(a)(2)) must be indicated on the plate as specified in 
Sec. 178.274(i).
    (ii) Issue an approval certificate for each portable tank or, in the 
case of a series of identical portable tanks manufactured to a single 
design type, for each series of portable tanks. The approval certificate 
must include all the information required to be displayed on the metal 
identification plate required by Sec. 178.274(i). The approval 
certificate must certify that the approval agency designated to approve 
the portable tank has approved the portable tank in accordance with the 
procedures in subpart E of part 107 of this subchapter and that the 
portable tank is suitable for its intended purpose and meets the 
requirements of this subchapter. When a series of portable tanks is 
manufactured without change in the design type, the certificate may be 
valid for the entire series of portable tanks representing a single 
design type. For UN portable tanks, the certificate must refer to the 
prototype test report, the hazardous material or group of hazardous 
materials allowed to be transported, the materials of construction of 
the shell and lining (when applicable) and an approval number. The 
approval number must consist of the distinguishing sign or mark of the 
country (``USA'' for the United States of America) where the approval 
was granted and a registration number.
    (iii) Retain a copy of each approval certificate.
    (8) For UN portable tanks, the approval certificate must also 
include the following:
    (i) The results of the applicable framework and rail impact test 
specified in part 180, subpart G, of this subchapter; and
    (ii) The results of the initial inspection and test in Sec. 
178.274(j).
    (9) The approval agency shall be independent from the manufacturer. 
The approval agency and the authorized inspector may be the same entity.
    (c) Manufacturers' responsibilities. The manufacturer is responsible 
for compliance with the applicable specifications for the design and 
construction of portable tanks. In addition to responsibility for 
compliance, manufacturers are responsible for ensuring that the 
contracted approval agency and authorized inspector, if applicable, are 
qualified, reputable and competent. The manufacturer of a portable tank 
shall--

[[Page 108]]

    (1) Comply with all the applicable requirements of the ASME Code and 
of this subpart including, but not limited to, ensuring that the quality 
control, design calculations and required tests are performed and that 
all aspects of the portable tank meet the applicable requirements.
    (2) Obtain and use a designated approval agency, if applicable, and 
obtain and use a DOT-designated approval agency to approve the design, 
construction and certification of the portable tank.
    (3) Provide a statement in the manufacturers' data report certifying 
that each portable tank that is manufactured complies with the relevant 
specification and all the applicable requirements of this subchapter.
    (4) Maintain records of the qualification of portable tanks for at 
least 5 years and provide copies to the approval agency, the owner or 
lessee of the tank. Upon request, provide these records to a 
representative of DOT.
    (d) Denial of application for approval. If an approval agency finds 
that a portable tank cannot be approved for any reason, it shall notify 
the applicant in writing and shall provide the applicant with the 
reasons for which the approval is denied. A copy of the notification 
letter shall be provided to the Associate Administrator. An applicant 
aggrieved by a decision of an approval agency may appeal the decision in 
writing, within 90 days of receipt, to the Associate Administrator.
    (e) Modifications to approved portable tanks. (1) Prior to 
modification of any UN portable tank which may affect conformance and 
the safe use of the portable tank, which may involve a change to the 
design type or which may affect its ability to retain hazardous material 
in transportation, the person desiring to make such modification shall 
inform the approval agency that issued the initial approval of the 
portable tank (or if unavailable, another approval agency) of the nature 
of the modification and request approval of the modification. The person 
desiring to modify the tank must supply the approval agency with three 
sets of all revised drawings, calculations, and test data relative to 
the intended modification.
    (2) A statement as to whether the intended modification has been 
examined and determined to be unacceptable by any approval agency. The 
written statement must include the name of the approving agency, the 
reason for nonacceptance, and the nature of changes made to the 
modification since its original rejection.
    (3) The approval agency shall review the request for modification, 
and if it is determined that the proposed modification is in full 
compliance with the relevant DOT specification, including a UN portable 
tank, the request shall be approved and the approval agency shall 
perform the following activities:
    (i) Return one set of the approved revised drawings, calculations, 
and test data to the applicant. The second and third sets of the 
approved revised drawings, calculations, and data shall be retained by 
the approval agency as required in Sec. 107.404(a)(3) of this 
subchapter.
    (ii) Ensure through appropriate inspection that all modifications 
conform to the revised drawings, calculations, and test data.
    (iii) Determine the extent to which retesting of the modified tank 
is necessary based on the nature of the proposed modification, and 
ensure that all required retests are satisfactorily performed.
    (iv) If modification to an approved tank alters any information on 
the approval certificate, issue a new approval certificate for the 
modified tank and ensure that any necessary changes are made to the 
metal identification plate. A copy of each newly issued approval 
certificate shall be retained by the approval agency and by the owner of 
each portable tank.
    (4) If the approval agency determines that the proposed modification 
is not in compliance with the relevant DOT specification, the approval 
agency shall deny the request in accordance with paragraph (d) of this 
section.
    (f) Termination of Approval Certificate. (1) The Associate 
Administrator may terminate an approval issued under this section if he 
determines that--
    (i) Information upon which the approval was based is fraudulent or 
substantially erroneous; or

[[Page 109]]

    (ii) Termination of the approval is necessary to adequately protect 
against risks to life and property; or
    (iii) The approval was not issued by the approval agency in good 
faith; or
    (iv) The portable tank does not meet the specification.
    (2) Before an approval is terminated, the Associate Administrator 
gives the interested party(ies):
    (i) Written notice of the facts or conduct believed to warrant the 
termination;
    (ii) Opportunity to submit oral and written evidence; and
    (iii) Opportunity to demonstrate or achieve compliance with the 
applicable requirements.
    (3) If the Associate Administrator determines that a certificate of 
approval must be terminated to preclude a significant and imminent 
adverse affect on public safety, he may terminate the certificate 
immediately. In such circumstances, the opportunities of paragraphs 
(f)(2) (ii) and (iii) of this section need not be provided prior to 
termination of the approval, but shall be provided as soon as 
practicable thereafter.

[66 FR 33439, June 21, 2001, as amended at 67 FR 61016, Sept. 27, 2002; 
68 FR 75748, 75751, Dec. 31, 2003; 72 FR 55695, Oct. 1, 2007]



Sec. 178.274  Specifications for UN portable tanks.

    (a) General. (1) Each UN portable tank must meet the requirements of 
this section. In addition to the requirements of this section, 
requirements specific to UN portable tanks used for liquid and solid 
hazardous materials, non-refrigerated liquefied gases and refrigerated 
liquefied gases are provided in Sec. Sec. 178.275, 178.276 and 178.277, 
respectively. Requirements for approval, maintenance, inspection, 
testing and use are provided in Sec. 178.273 and part 180, subpart G, 
of this subchapter. Any portable tank which meets the definition of a 
``container'' within the terms of the International Convention for Safe 
Containers (CSC) must meet the requirements of the CSC as amended and 49 
CFR parts 450 through 453 and must have a CSC safety approval plate.
    (2) In recognition of scientific and technological advances, the 
technical requirements applicable to UN portable tanks may be varied if 
approved by the Associate Administrator and the portable tank is shown 
to provide a level of safety equal to or exceeding the requirements of 
this subchapter. Portable tanks approved to alternative technical 
requirements must be marked ``Alternative Arrangement'' as specified in 
paragraph (i) of this section.
    (3) Definitions. The following definitions apply for the purposes of 
design and construction of UN portable tanks under this subpart:
    Alternate Arrangement portable tank means a UN portable tank that 
has been approved to alternative technical requirements or testing 
methods other than those specified for UN portable tanks in part 178 or 
part 180 of this subchapter.
    Approval agency means the designated approval agency authorized to 
approve the portable tank in accordance with the procedures in subpart E 
of part 107 of this subchapter.
    Design pressure is defined according to the hazardous materials 
intended to be transported in the portable tank. See Sec. Sec. 178.275, 
178.276 and 178.277, as applicable.
    Design type means a portable tank or series of portable tanks made 
of materials of the same material specifications and thicknesses, 
manufactured by a single manufacturer, using the same fabrication 
techniques (for example, welding procedures) and made with equivalent 
structural equipment, closures, and service equipment.
    Fine grain steel means steel that has a ferritic grain size of 6 or 
finer when determined in accordance with ASTM E 112-96 (IBR, see Sec. 
171.7 of this subchapter).
    Fusible element means a non-reclosing pressure relief device that is 
thermally activated and that provides protection against excessive 
pressure buildup in the portable tank developed by exposure to heat, 
such as from a fire (see Sec. 178.275(g)).
    Jacket means the outer insulation cover or cladding which may be 
part of the insulation system.
    Leakage test means a test using gas to subject the shell and its 
service equipment to an internal pressure.

[[Page 110]]

    Maximum allowable working pressure (MAWP) is defined according to 
the hazardous materials intended to be transported in the portable tank. 
See Sec. Sec. 178.275, 178.276 and 178.277, as applicable.
    Maximum permissible gross mass (MPGM) means the sum of the tare mass 
of the portable tank and the heaviest hazardous material authorized for 
transportation.
    Mild steel means a steel with a guaranteed minimum tensile strength 
of 360 N/mm\2\ to 440 N/mm\2\ and a guaranteed minimum elongation at 
fracture as specified in paragraph (c)(10) of this section.
    Offshore portable tank means a portable tank specially designed for 
repeated use in the transportation of hazardous materials to, from and 
between offshore facilities. An offshore portable tank is designed and 
constructed in accordance with the Guidelines for the Approval of 
Containers Handled in Open Seas specified in the IMDG Code (IBR, see 
Sec. 171.7 of this subchapter).
    Reference steel means a steel with a tensile strength of 370 N/mm\2\ 
and an elongation at fracture of 27%.
    Service equipment means measuring instruments and filling, 
discharge, venting, safety, heating, cooling and insulating devices.
    Shell means the part of the portable tank which retains the 
hazardous materials intended for transportation, including openings and 
closures, but does not include service equipment or external structural 
equipment.
    Structural equipment means the reinforcing, fastening, protective 
and stabilizing members external to the shell.
    Test pressure means the maximum gauge pressure at the top of the 
shell during the hydraulic pressure test equal to not less than 1.5 
times the design pressure for liquids and 1.3 for liquefied compressed 
gases and refrigerated liquefied gases. In some instances a pneumatic 
test is authorized as an alternative to the hydraulic test. The minimum 
test pressures for portable tanks intended for specific liquid and solid 
hazardous materials are specified in the applicable portable tank T 
codes (such as T1-T23) assigned to these hazardous materials in the 
Sec. 172.101 Table of this subchapter.
    (b) General design and construction requirements. (1) The design 
temperature range for the shell must be -40 [deg]C to 50 [deg]C (-40 
[deg]F to 122 [deg]F) for hazardous materials transported under normal 
conditions of transportation, except for portable tanks used for 
refrigerated liquefied gases where the minimum design temperature must 
not be higher than the lowest (coldest) temperature (for example, 
service temperature) of the contents during filling, discharge or 
transportation. For hazardous materials handled under elevated 
temperature conditions, the design temperature must not be less than the 
maximum temperature of the hazardous material during filling, discharge 
or transportation. More severe design temperatures must be considered 
for portable tanks subjected to severe climatic conditions (for example, 
portable tanks transported in arctic regions). Shells must be designed 
and constructed in accordance with the requirements in Section VIII of 
the ASME Code (IBR, see Sec. 171.7 of this subchapter), except as 
limited or modified in this subchapter. For portable tanks used for 
liquid or solid hazardous materials, a design code other than the ASME 
Code may be used if approved by the Associate Administrator. Portable 
tanks must have an ASME certification and U stamp when used for Hazard 
Zone A or B toxic by inhalation liquids, or when used for non-
refrigerated or refrigerated liquefied compressed gases. Shells must be 
made of metallic materials suitable for forming. Non-metallic materials 
may be used for the attachments and supports between the shell and 
jacket, provided their material properties at the minimum and maximum 
design temperatures are proven to be sufficient. For welded shells, only 
a material whose weldability has been fully demonstrated may be used. 
Welds must be of high quality and conform to a level of integrity at 
least equivalent to the welding requirements specified in Section VIII 
of the ASME Code for the welding of pressure vessels. When the 
manufacturing process or the materials make it necessary, the shells 
must be suitably heat-treated to guarantee adequate toughness in the 
weld and in the heat-affected zones. In choosing the

[[Page 111]]

material, the design temperature range must be taken into account with 
respect to risk of brittle fracture, stress corrosion cracking, 
resistance to impact, and suitability for the hazardous materials 
intended for transportation in the portable tank. When fine grain steel 
is used, the guaranteed value of the yield strength must be not more 
than 460 N/mm\2\ and the guaranteed value of the upper limit of the 
tensile strength must be not more than 725 N/mm\2\ according to the 
material specification. Aluminum may not be used as a construction 
material for the shells of portable tanks intended for the transport of 
non-refrigerated liquefied gases. For portable tanks intended for the 
transport of liquid or solid hazardous materials, aluminum may only be 
used as a construction material for portable tank shells if approved by 
the Associate Administrator. Portable tank materials must be suitable 
for the external environment where they will be transported, taking into 
account the determined design temperature range. Portable tanks shall be 
designed to withstand, without loss of contents, at least the internal 
pressure due to the contents and the static, dynamic and thermal loads 
during normal conditions of handling and transportation. The design must 
take into account the effects of fatigue, caused by repeated application 
of these loads through the expected life of the portable tank.
    (2) Portable tank shells, fittings, and pipework shall be 
constructed from materials that are:
    (i) Compatible with the hazardous materials intended to be 
transported; or
    (ii) Properly passivated or neutralized by chemical reaction, if 
applicable; or
    (iii) For portable tanks used for liquid and solid materials, lined 
with corrosion-resistant material directly bonded to the shell or 
attached by equivalent means.
    (3) Gaskets and seals shall be made of materials that are compatible 
with the hazardous materials intended to be transported.
    (4) When shells are lined, the lining must be compatible with the 
hazardous materials intended to be transported, homogeneous, non-porous, 
free from perforations, sufficiently elastic and compatible with the 
thermal expansion characteristics of the shell. The lining of every 
shell, shell fittings and piping must be continuous and must extend 
around the face of any flange. Where external fittings are welded to the 
tank, the lining must be continuous through the fitting and around the 
face of external flanges. Joints and seams in the lining must be made by 
fusing the material together or by other equally effective means.
    (5) Contact between dissimilar metals which could result in damage 
by galvanic action must be prevented by appropriate measures.
    (6) The construction materials of the portable tank, including any 
devices, gaskets, linings and accessories, must not adversely affect or 
react with the hazardous materials intended to be transported in the 
portable tank.
    (7) Portable tanks must be designed and constructed with supports 
that provide a secure base during transportation and with suitable 
lifting and tie-down attachments.
    (c) Design criteria. (1) Portable tanks and their fastenings must, 
under the maximum permissible loads and maximum permissible working 
pressures, be capable of absorbing the following separately applied 
static forces (for calculation purposes, acceleration due to gravity (g) 
=9.81m/s\2\):
    (i) In the direction of travel: 2g (twice the MPGM multiplied by the 
acceleration due to gravity);
    (ii) Horizontally at right angles to the direction of travel: 1g 
(the MPGM multiplied by the acceleration due to gravity);
    (iii) Vertically upwards: 1g (the MPGM multiplied by the 
acceleration due to gravity); and
    (iv) Vertically downwards: 2g (twice the MPGM multiplied by the 
acceleration due to gravity).
    (2) Under each of the forces specified in paragraph (c)(1) of this 
section, the safety factor must be as follows:
    (i) For metals having a clearly defined yield point, a design margin 
of 1.5 in relation to the guaranteed yield strength; or
    (ii) For metals with no clearly defined yield point, a design margin 
of 1.5 in relation to the guaranteed 0.2%

[[Page 112]]

proof strength and, for austenitic steels, the 1% proof strength.
    (3) The values of yield strength or proof strength must be the 
values according to recognized material standards. When austenitic 
steels are used, the specified minimum values of yield strength or proof 
strength according to the material standards may be increased by up to 
15% for portable tanks used for liquid and solid hazardous materials, 
other than toxic by inhalation liquids meeting the criteria of Hazard 
Zone A or Hazard Zone B (see Sec. 173.133 of this subchapter), when 
these greater values are attested in the material inspection 
certificate.
    (4) Portable tanks must be capable of being electrically grounded to 
prevent dangerous electrostatic discharge when they are used for Class 2 
flammable gases or Class 3 flammable liquids, including elevated 
temperature materials transported at or above their flash point.
    (5) For shells of portable tanks used for liquefied compressed 
gases, the shell must consist of a circular cross section. Shells must 
be of a design capable of being stress-analyzed mathematically or 
experimentally by resistance strain gauges as specified in UG-101 of 
Section VIII of the ASME Code, or other methods approved by the 
Associate Administrator.
    (6) Shells must be designed and constructed to withstand a hydraulic 
test pressure of not less than 1.5 times the design pressure for 
portable tanks used for liquids and 1.3 times the design pressure for 
portable tanks used for liquefied compressed gases. Specific 
requirements are provided for each hazardous material in the applicable 
T Code or portable tank special provision specified in the Sec. 172.101 
Table of this subchapter. The minimum shell thickness requirements must 
also be taken into account.
    (7) For metals exhibiting a clearly defined yield point or 
characterized by a guaranteed proof strength (0.2% proof strength, 
generally, or 1% proof strength for austenitic steels), the primary 
membrane stress [sigma] (sigma) in the shell must not exceed 0.75 Re or 
0.50 Rm, whichever is lower, at the test pressure, where:

Re = yield strength in N/mm\2\, or 0.2% proof strength or, for 
austenitic steels, 1% proof strength;
Rm = minimum tensile strength in N/mm\2\.

    (8) The values of Re and Rm to be used must be the specified minimum 
values according to recognized material standards. When austenitic 
steels are used, the specified minimum values for Re and Rm according to 
the material standards may be increased by up to 15% when greater values 
are attested in the material inspection certificate.
    (9) Steels which have a Re/Rm ratio of more than 0.85 are not 
allowed for the construction of welded shells. The values of Re and Rm 
to be used in determining this ratio must be the values specified in the 
material inspection certificate.
    (10) Steels used in the construction of shells must have an 
elongation at fracture, in percentage, of not less than 10,000/Rm with 
an absolute minimum of 16% for fine grain steels and 20% for other 
steels.
    (11) For the purpose of determining actual values for materials for 
sheet metal, the axis of the tensile test specimen must be at right 
angles (transversely) to the direction of rolling. The permanent 
elongation at fracture must be measured on test specimens of rectangular 
cross sections in accordance with ISO 6892 (IBR, see Sec. 171.7 of this 
subchapter), using a 50 mm gauge length.
    (d) Minimum shell thickness. (1) The minimum shell thickness must be 
the greatest thickness of the following:
    (i) the minimum thickness determined in accordance with the 
requirements of paragraphs (d)(2) through (d)(7) of this section;
    (ii) the minimum thickness determined in accordance with Section 
VIII of the ASME Code or other approved pressure vessel code; or
    (iii) the minimum thickness specified in the applicable T code or 
portable tank special provision indicated for each hazardous material in 
the Sec. 172.101 Table of this subchapter.
    (2) Shells (cylindrical portions, heads and manhole covers) not more 
than 1.80 m in diameter may not be less than 5 mm thick in the reference 
steel or of

[[Page 113]]

equivalent thickness in the metal to be used. Shells more than 1.80 m in 
diameter may not be less than 6 mm (0.2 inches) thick in the reference 
steel or of equivalent thickness in the metal to be used. For portable 
tanks used only for the transportation of powdered or granular solid 
hazardous materials of Packing Group II or III, the minimum thickness 
requirement may be reduced to 5 mm in the reference steel or of 
equivalent thickness in the metal to be used regardless of the shell 
diameter. For vacuum-insulated tanks, the aggregate thickness of the 
jacket and the shell must correspond to the minimum thickness prescribed 
in this paragraph, with the thickness of the shell itself not less than 
the minimum thickness prescribed in paragraph (d)(3) of this section.
    (3) When additional protection against shell damage is provided in 
the case of portable tanks used for liquid and solid hazardous materials 
requiring test pressures less than 2.65 bar (265.0 kPa), subject to 
certain limitations specified in the UN Recommendations (IBR, see Sec. 
171.7 of this subchapter), the Associate Administrator may approve a 
reduced minimum shell thickness.
    (4) The cylindrical portions, heads and manhole covers of all shells 
must not be less than 3 mm (0.1 inch) thick regardless of the material 
of construction, except for portable tanks used for liquefied compressed 
gases where the cylindrical portions, ends (heads) and manhole covers of 
all shells must not be less than 4 mm (0.2 inch) thick regardless of the 
material of construction.
    (5) When steel is used, that has characteristics other than that of 
reference steel, the equivalent thickness of the shell and heads must be 
determined according to the following formula:
[GRAPHIC] [TIFF OMITTED] TN21JN01.005

Where:

e1 = required equivalent thickness (in mm) of the metal to be 
          used;
e0 = minimum thickness (in mm) of the reference steel 
          specified in the applicable T code or portable tank special 
          provision indicated for each material in the Sec. 172.101 
          Table of this subchapter;
d1 = 1.8m, unless the formula is used to determine the 
          equivalent minimum thickness for a portable tank shell that is 
          required to have a minimum thickness of 8mm or 10mm according 
          to the applicable T code indicated in the Sec. 172.101 Table 
          of this subchapter. When reference steel thicknesses of 8mm or 
          10mm are specified, d1 is equal to the actual 
          diameter of the shell but not less than 1.8m;
Rm1 = guaranteed minimum tensile strength (in N/mm \2\) of 
          the metal to be used;
A1 = guaranteed minimum elongation at fracture (in %) of the 
          metal to be used according to recognized material standards.

    (6) The wall and all parts of the shell may not have a thickness 
less than that prescribed in paragraphs (d)(2), (d)(3) and (d)(4) of 
this section. This thickness must be exclusive of any corrosion 
allowance.
    (7) There must be no sudden change of plate thickness at the 
attachment of the heads to the cylindrical portion of the shell.
    (e) Service equipment. (1) Service equipment must be arranged so 
that it is protected against the risk of mechanical damage by external 
forces during handling and transportation. When the connections between 
the frame and the shell allow relative movement between the sub-
assemblies, the equipment must be fastened to allow such movement 
without risk of damage to any working part. The external discharge 
fittings (pipe sockets, shut-off devices) and the internal stop-valve 
and its seating must be protected against mechanical damage by external 
forces (for example, by using shear sections). Each internal self-
closing stop-valve must be protected by a shear section or sacrificial 
device located outboard of the valve. The shear section or sacrificial 
device must break at no more than 70% of the load that would cause 
failure of the internal self-closing stop valve. The filling and 
discharge devices (including flanges or threaded plugs) and any 
protective caps must be capable of being secured against unintended 
opening.
    (2) Each filling or discharge opening of a portable tank must be 
clearly marked to indicate its function.
    (3) Each stop-valve or other means of closure must be designed and 
constructed to a rated pressure not less than the MAWP of the shell 
taking

[[Page 114]]

into account the temperatures expected during transport. All stop-valves 
with screwed spindles must close by a clockwise motion of the handwheel. 
For other stop-valves, the position (open and closed) and direction of 
closure must be clearly indicated. All stop-valves must be designed to 
prevent unintentional opening.
    (4) Piping must be designed, constructed and installed to avoid the 
risk of damage due to thermal expansion and contraction, mechanical 
shock and vibration. All piping must be of a suitable metallic material. 
Welded pipe joints must be used wherever possible.
    (5) Joints in copper tubing must be brazed or have an equally strong 
metal union. The melting point of brazing materials must be no lower 
than 525 [deg]C (977 [deg]F). The joints must not decrease the strength 
of the tubing, such as may happen when cutting threads. Brazed joints 
are not authorized for portable tanks intended for refrigerated 
liquefied gases.
    (6) The burst pressure of all piping and pipe fittings must be 
greater than the highest of four times the MAWP of the shell or four 
times the pressure to which it may be subjected in service by the action 
of a pump or other device (except pressure relief devices).
    (7) Ductile metals must be used in the construction of valves and 
accessories.
    (f) Pressure relief devices--(1) Marking of pressure relief devices. 
Every pressure relief device must be clearly and permanently marked with 
the following:
    (i) the pressure (in bar or kPa) or temperature for fusible elements 
(in [deg]C) at which it is set to discharge;
    (ii) the allowable tolerance at the discharge pressure for reclosing 
devices;
    (iii) the reference temperature corresponding to the rated pressure 
for frangible discs;
    (iv) the allowable temperature tolerance for fusible elements;
    (v) The rated flow capacity of the spring loaded pressure relief 
devices, frangible disc or fusible elements in standard cubic meters of 
air per second (m\3\/s). For spring loaded pressure relief device the 
rated flow capacity shall be determined according to ISO 4126-1 (IBR, 
see Sec. 171.7 of this subchapter); and
    (vi) when practicable, the device must show the manufacturer's name 
and product number.
    (2) Connections to pressure relief devices. Connections to pressure 
relief devices must be of sufficient size to enable the required 
discharge to pass unrestricted to the safety device. No stop-valve may 
be installed between the shell and the pressure relief devices except 
where duplicate devices are provided for maintenance or other reasons 
and the stop-valves serving the devices actually in use are locked open 
or the stop-valves are interlocked so that at least one of the devices 
is always in use. There must be no obstruction in an opening leading to 
a vent or pressure relief device which might restrict or cut-off the 
flow from the shell to that device. Vents or pipes from the pressure 
relief device outlets, when used, must deliver the relieved vapor or 
liquid to the atmosphere in conditions of minimum back-pressure on the 
relieving devices.
    (3) Location of pressure relief devices. (i) Each pressure relief 
device inlet must be situated on top of the shell in a position as near 
the longitudinal and transverse center of the shell as reasonably 
practicable. All pressure relief device inlets must, under maximum 
filling conditions, be situated in the vapor space of the shell and the 
devices must be so arranged as to ensure that any escaping vapor is not 
restricted in any manner. For flammable hazardous materials, the 
escaping vapor must be directed away from the shell in such a manner 
that it cannot impinge upon the shell. For refrigerated liquefied gases, 
the escaping vapor must be directed away from the tank and in such a 
manner that it cannot impinge upon the tank. Protective devices which 
deflect the flow of vapor are permissible provided the required relief-
device capacity is not reduced.
    (ii) Provisions must be implemented to prevent unauthorized persons 
from access to the pressure relief devices and to protect the devices 
from damage caused by the portable tank overturning.
    (g) Gauging devices. Unless a portable tank is intended to be filled 
by weight, it must be equipped with one or more gauging devices. Glass 
level-gauges and

[[Page 115]]

gauges made of other fragile material, which are in direct communication 
with the contents of the tank are prohibited. A connection for a vacuum 
gauge must be provided in the jacket of a vacuum-insulated portable 
tank.
    (h) Portable tank supports, frameworks, lifting and tie-down 
attachments. (1) Portable tanks must be designed and constructed with a 
support structure to provide a secure base during transport. The forces 
and safety factors specified in paragraphs (c)(1) and (c)(2) of this 
section, respectively, must be taken into account in this aspect of the 
design. Skids, frameworks, cradles or other similar structures are 
acceptable.
    (2) The combined stresses caused by portable tank mountings (for 
example, cradles, framework, etc.) and portable tank lifting and tie-
down attachments must not cause stress that would damage the shell in a 
manner that would compromise its lading retention capability. Permanent 
lifting and tie-down attachments must be fitted to all portable tanks. 
Preferably they should be fitted to the portable tank supports but may 
be secured to reinforcing plates located on the shell at the points of 
support. Each portable tank must be designed so that the center of 
gravity of the filled tank is approximately centered within the points 
of attachment for lifting devices.
    (3) In the design of supports and frameworks, the effects of 
environmental corrosion must be taken into account.
    (4) Forklift pockets must be capable of being closed off. The means 
of closing forklift pockets must be a permanent part of the framework or 
permanently attached to the framework. Single compartment portable tanks 
with a length less than 3.65 m (12 ft.) need not have forklift pockets 
that are capable of being closed off provided that:
    (i) The shell, including all the fittings, are well protected from 
being hit by the forklift blades; and
    (ii) The distance between forklift pockets (measured from the center 
of each pocket) is at least half of the maximum length of the portable 
tank.
    (5) During transport, portable tanks must be adequately protected 
against damage to the shell, and service equipment resulting from 
lateral and longitudinal impact and overturning, or the shell and 
service equipment must be constructed to withstand the forces resulting 
from impact or overturning. External fittings must be protected so as to 
preclude the release of the shell contents upon impact or overturning of 
the portable tank on its fittings. Examples of protection include:
    (i) Protection against lateral impact which may consist of 
longitudinal bars protecting the shell on both sides at the level of the 
median line;
    (ii) Protection of the portable tank against overturning which may 
consist of reinforcement rings or bars fixed across the frame;
    (iii) Protection against rear impact which may consist of a bumper 
or frame;
    (iv) Protection of the shell against damage from impact or 
overturning by use of an ISO frame in accordance with ISO 1496-3 (IBR, 
see Sec. 171.7 of this subchapter); and
    (v) Protection of the portable tank from impact or damage that may 
result from overturning by an insulation jacket.
    (i) Marking. (1) Every portable tank must be fitted with a corrosion 
resistant metal plate permanently attached to the portable tank in a 
conspicuous place and readily accessible for inspection. When the plate 
cannot be permanently attached to the shell, the shell must be marked 
with at least the information required by Section VIII of the ASME Code. 
At a minimum, the following information must be marked on the plate by 
stamping or by any other equivalent method:

Country of manufacture
U N
Approval Country
Approval Number
Alternative Arrangements (see Sec. 178.274(a)(2)) ``AA''
Manufacturer's name or mark
Manufacturer's serial number
Approval Agency (Authorized body for the design approval)
Owner's registration number
Year of manufacture
Pressure vessel code to which the shell is designed
Test pressure--------bar gauge.
MAWP--------bar gauge.

[[Page 116]]

External design pressure (not required for portable tanks used for 
refrigerated liquefied gases)--------bar gauge.
Design temperature range-------- [deg]C to-------- [deg]C. (For portable 
tanks used for refrigerated liquefied gases, the minimum design 
temperature must be marked.)
Water capacity at 20 [deg]C/--------liters.
Water capacity of each compartment at 20 [deg]C--------liters.
Initial pressure test date and witness identification.
MAWP for heating/cooling system--------bar gauge.
Shell material(s) and material standard reference(s).
Equivalent thickness in reference steel--------mm.
Lining material (when applicable).
Date and type of most recent periodic test(s).
Month--------Year-------- Test pressure--------bar gauge.
Stamp of approval agency that performed or witnessed the most recent 
test.

    For portable tanks used for refrigerated liquefied gases:

Either ``thermally insulated'' or ``vacuum insulated''--------.
Effectiveness of the insulation system (heat influx)--------Watts (W).
Reference holding time--------days or hours and initial pressure--------
bar/kPa gauge and degree of filling--------in kg for each refrigerated 
liquefied gas permitted for transportation.

    (2) The following information must be marked either on the portable 
tank itself or on a metal plate firmly secured to the portable tank:

Name of the operator.
Name of hazardous materials being transported and maximum mean bulk 
temperature (except for refrigerated liquefied gases, the name and 
temperature are only required when the maximum mean bulk temperature is 
higher than 50 [deg]C).
Maximum permissible gross mass (MPGM)--------kg.
Unladen (tare) mass--------kg.

    Note to paragraph (i)(2): For the identification of the hazardous 
materials being transported refer to part 172 of this subchapter.

    (3) If a portable tank is designed and approved for open seas 
operations, such as offshore oil exploration, in accordance with the 
IMDG Code, the words ``OFFSHORE PORTABLE TANK'' must be marked on the 
identification plate.
    (j) Initial inspection and test. The initial inspection and test of 
a portable tank must include the following:
    (1) A check of the design characteristics.
    (2) An internal and external examination of the portable tank and 
its fittings, taking into account the hazardous materials to be 
transported. For UN portable tanks used for refrigerated liquefied 
gases, a pressure test using an inert gas may be conducted instead of a 
hydrostatic test. An internal inspection is not required for a portable 
tank used for the dedicated transportation of refrigerated liquefied 
gases that are not filled with an inspection opening.
    (3) A pressure test as specified in paragraph (i) of this section.
    (4) A leakage test.
    (5) A test of the satisfactory operation of all service equipment 
including pressure relief devices must also be performed. When the shell 
and its fittings have been pressure-tested separately, they must be 
subjected to a leakage test after reassembly. All welds, subject to full 
stress level in the shell, must be inspected during the initial test by 
radiographic, ultrasonic, or another suitable non-destructive test 
method. This does not apply to the jacket.
    (6) Effective January 1, 2008, each new UN portable tank design type 
meeting the definition of ``container'' in the Convention for Safe 
Containers (CSC) (see 49 CFR 450.3(a)(2)) must be subjected to the 
dynamic longitudinal impact test prescribed in Part IV, Section 40 of 
the UN Manual of Tests and Criteria (see IBR, Sec. 171.7 of this 
subchapter). A UN portable tank design type impact-tested prior to 
January 1, 2008, in accordance with the requirements of this section in 
effect on October 1, 2005, need not be retested. UN portable tanks used 
for the dedicated transportation of ``Helium, refrigerated liquid,'' 
UN1963, and ``Hydrogen, refrigerated liquid,'' UN1966, that are marked 
``NOT FOR RAIL TRANSPORT'' in letters of a minimum height of 10 cm (4 
inches) on at least two sides of the portable tank are excepted from the 
dynamic longitudinal impact test.
    (7) The following tests must be completed on a portable tank or a 
series of portable tanks designed and constructed to a single design 
type that is also a CSC container without leakage or deformation that 
would render the

[[Page 117]]

portable tank unsafe for transportation and use:
    (i) Longitudinal inertia. The portable tank loaded to its maximum 
gross weight must be positioned with its longitudinal axis vertical. It 
shall be held in this position for five minutes by support at the lower 
end of the base structure providing vertical and lateral restraint and 
by support at the upper end of the base structure providing lateral 
restraint only.
    (ii) Lateral inertia. The portable tank loaded to its maximum gross 
weight must be positioned for five minutes with its transverse axis 
vertical. It shall be held in this position for five minutes by support 
at the lower side of the base structure providing vertical and lateral 
restraint and by support at the upper side of the base structure 
providing lateral restraint only.

[66 FR 33440, June 21, 2001, as amended at 67 FR 15744, Apr. 3, 2002; 68 
FR 45041, July 31, 2003; 68 FR 57633, Oct. 6, 2003; 68 FR 75751, Dec. 
31, 2003; 69 FR 76185, Dec. 20, 2004; 70 FR 34399, June 14, 2005; 71 FR 
78634, Dec. 29, 2006; 72 FR 55696, Oct. 1, 2007; 73 FR 4719, Jan. 28, 
2008]

    Editorial Note: At 68 FR 57633, Oct. 6, 2003, Sec. 178.274 was 
amended in paragraph (b)(1); however, the amendment could not be 
incorporated due to inaccurate amendatory instruction.



Sec. 178.275  Specification for UN Portable Tanks intended for the 
transportation of liquid and solid hazardous materials.

    (a) In addition to the requirements of Sec. 178.274, this section 
sets forth definitions and requirements that apply to UN portable tanks 
intended for the transportation of liquid and solid hazardous materials.
    (b) Definitions and requirements--(1) Design pressure means the 
pressure to be used in calculations required by the recognized pressure 
vessel code. The design pressure must not be less than the highest of 
the following pressures:
    (i) The maximum effective gauge pressure allowed in the shell during 
filling or discharge; or
    (ii) The sum of--
    (A) The absolute vapor pressure (in bar) of the hazardous material 
at 65 [deg]C, minus 1 bar (149 [deg]F, minus 100 kPa);
    (B) The partial pressure (in bar) of air or other gases in the 
ullage space, resulting from their compression during filling without 
pressure relief by a maximum ullage temperature of 65 [deg]C (149 
[deg]F) and a liquid expansion due to an increase in mean bulk 
temperature of 35 [deg]C (95 [deg]F); and
    (C) A head pressure determined on the basis of the forces specified 
in Sec. 178.274(c) of this subchapter, but not less than 0.35 bar (35 
kPa).
    (2) Maximum allowable working pressure (MAWP) means a pressure that 
must not be less than the highest of the following pressures measured at 
the top of the shell while in operating position:
    (i) The maximum effective gauge pressure allowed in the shell during 
filling or discharge; or
    (ii) The maximum effective gauge pressure to which the shell is 
designed which must be not less than the design pressure.
    (c) Service equipment. (1) In addition to the requirements specified 
in Sec. 178.274, for service equipment, all openings in the shell, 
intended for filling or discharging the portable tank must be fitted 
with a manually operated stop-valve located as close to the shell as 
reasonably practicable. Other openings, except for openings leading to 
venting or pressure relief devices, must be equipped with either a stop-
valve or another suitable means of closure located as close to the shell 
as reasonably practicable.
    (2) All portable tanks must be fitted with a manhole or other 
inspection openings of a suitable size to allow for internal inspection 
and adequate access for maintenance and repair of the interior. 
Compartmented portable tanks must have a manhole or other inspection 
openings for each compartment.
    (3) For insulated portable tanks, top fittings must be surrounded by 
a spill collection reservoir with suitable drains.
    (4) Piping must be designed, constructed and installed to avoid the 
risk of damage due to thermal expansion and contraction, mechanical 
shock and vibration. All piping must be of a suitable metallic material. 
Welded pipe joints must be used wherever possible.

[[Page 118]]

    (d) Bottom openings. (1) Certain hazardous materials may not be 
transported in portable tanks with bottom openings. When the applicable 
T code or portable tank special provision, as referenced for materials 
in the Sec. 172.101 Table of this subchapter, specifies that bottom 
openings are prohibited, there must be no openings below the liquid 
level of the shell when it is filled to its maximum permissible filling 
limit. When an existing opening is closed, it must be accomplished by 
internally and externally welding one plate to the shell.
    (2) Bottom discharge outlets for portable tanks carrying certain 
solid, crystallizable or highly viscous hazardous materials must be 
equipped with at least two serially fitted and mutually independent 
shut-off devices. Use of only two shut-off devices is only authorized 
when this paragraph is referenced in the applicable T Code indicated for 
each hazardous material in the Sec. 172.101 Table of this subchapter. 
The design of the equipment must be to the satisfaction of the approval 
agency and must include:
    (i) An external stop-valve fitted as close to the shell as 
reasonably practicable; and
    (ii) A liquid tight closure at the end of the discharge pipe, which 
may be a bolted blank flange or a screw cap.
    (3) Except as provided in paragraph (d)(2) of this section, every 
bottom discharge outlet must be equipped with three serially fitted and 
mutually independent shut-off devices. The design of the equipment must 
include:
    (i) A self-closing internal stop-valve, which is a stop-valve within 
the shell or within a welded flange or its companion flange, such that:
    (A) The control devices for the operation of the valve are designed 
to prevent any unintended opening through impact or other inadvertent 
act;
    (B) The valve is operable from above or below;
    (C) If possible, the setting of the valve (open or closed) must be 
capable of being verified from the ground;
    (D) Except for portable tanks having a capacity less than 1,000 
liters (264.2 gallons), it must be possible to close the valve from an 
accessible position on the portable tank that is remote from the valve 
itself within 30 seconds of actuation; and
    (E) The valve must continue to be effective in the event of damage 
to the external device for controlling the operation of the valve;
    (ii) An external stop-valve fitted as close to the shell as 
reasonably practicable;
    (iii) A liquid tight closure at the end of the discharge pipe, which 
may be a bolted blank flange or a screw cap; and
    (iv) For UN portable tanks, with bottom outlets, used for the 
transportation of liquid hazardous materials that are Class 3, PG I or 
II, or PG III with a flash point of less than 100 [deg]F (38 [deg]C); 
Division 5.1, PG I or II; or Division 6.1, PG I or II, the remote means 
of closure must be capable of thermal activation. The thermal means of 
activation must activate at a temperature of not more than 250 [deg]F 
(121 [deg]C).
    (e) Pressure relief devices. All portable tanks must be fitted with 
at least one pressure relief device. All relief devices must be 
designed, constructed and marked in accordance with the requirements of 
this subchapter.
    (f) Vacuum-relief devices. (1) A shell which is to be equipped with 
a vacuum-relief device must be designed to withstand, without permanent 
deformation, an external pressure of not less than 0.21 bar (21.0 kPa). 
The vacuum-relief device must be set to relieve at a vacuum setting not 
greater than -0.21 bar (-21.0 kPa) unless the shell is designed for a 
higher external over pressure, in which case the vacuum-relief pressure 
of the device to be fitted must not be greater than the tank design 
vacuum pressure. A shell that is not fitted with a vacuum-relief device 
must be designed to withstand, without permanent deformation, an 
external pressure of not less than 0.4 bar (40.0 kPa).
    (2) Vacuum-relief devices used on portable tanks intended for the 
transportation of hazardous materials meeting the criteria of Class 3, 
including elevated temperature hazardous materials transported at or 
above their flash point, must prevent the immediate passage of flame 
into the shell or the portable tank must have a shell capable of 
withstanding, without leakage, an internal explosion resulting

[[Page 119]]

from the passage of flame into the shell.
    (g) Pressure relief devices. (1) Each portable tank with a capacity 
not less than 1,900 liters (501.9 gallons) and every independent 
compartment of a portable tank with a similar capacity, must be provided 
with one or more pressure relief devices of the reclosing type. Such 
portable tanks may, in addition, have a frangible disc or fusible 
element in parallel with the reclosing devices, except when the 
applicable T code assigned to a hazardous material requires that the 
frangible disc precede the pressure relief device, according to 
paragraph (g)(3) of this section, or when no bottom openings are 
allowed. The pressure relief devices must have sufficient capacity to 
prevent rupture of the shell due to over pressurization or vacuum 
resulting from filling, discharging, heating of the contents or fire.
    (2) Pressure relief devices must be designed to prevent the entry of 
foreign matter, the leakage of liquid and the development of any 
dangerous excess pressure.
    (3) When required for certain hazardous materials by the applicable 
T code or portable tank special provision specified for a hazardous 
material in the Sec. 172.101 Table of this subchapter, portable tanks 
must have a pressure relief device consistent with the requirements of 
this subchapter. Except for a portable tank in dedicated service that is 
fitted with an approved relief device constructed of materials 
compatible with the hazardous material, the relief device system must 
include a frangible disc preceding (such as, between the lading and the 
reclosing pressure relief device) a reclosing pressure relief device. A 
pressure gauge or suitable tell-tale indicator for the detection of disc 
rupture, pin-holing or leakage must be provided in the space between the 
frangible disc and the pressure relief device to allow the portable tank 
operator to check to determine if the disc is leak free. The frangible 
disc must rupture at a nominal pressure 10% above the start-to-discharge 
pressure of the reclosable pressure relief device.
    (4) Every portable tank with a capacity less than 1,900 liters 
(501.9 gallons) must be fitted with a pressure relief device which, 
except as provided in paragraph (g)(3) of this section, may be a 
frangible disc when this disc is set to rupture at a nominal pressure 
equal to the test pressure at any temperature within the design 
temperature range.
    (5) When the shell is fitted for pressure discharge, a suitable 
pressure relief device must provide the inlet line to the portable tank 
and set to operate at a pressure not higher than the MAWP of the shell, 
and a stop-valve must be fitted as close to the shell as practicable to 
minimize the potential for damage.
    (6) Setting of pressure relief devices. (i) Pressure relief devices 
must operate only in conditions of excessive rise in temperature. The 
shell must not be subject to undue fluctuations of pressure during 
normal conditions of transportation.
    (ii) The required pressure relief device must be set to start to 
discharge at a nominal pressure of five-sixths of the test pressure for 
shells having a test pressure of not more than 4.5 bar (450 kPa) and 
110% of two-thirds of the test pressure for shells having a test 
pressure of more than 4.5 bar (450 kPa). A self-closing relief device 
must close at a pressure not more than 10% below the pressure at which 
the discharge starts. The device must remain closed at all lower 
pressures. This requirement does not prevent the use of vacuum-relief or 
combination pressure relief and vacuum-relief devices.
    (h) Fusible elements. Fusible elements must operate at a temperature 
between 110 [deg]C (230 [deg]F) and 149 [deg]C (300.2 [deg]F), provided 
that the pressure in the shell at the fusing temperature will not exceed 
the test pressure. They must be placed at the top of the shell with 
their inlets in the vapor space and in no case may they be shielded from 
external heat. Fusible elements must not be utilized on portable tanks 
with a test pressure which exceeds 2.65 bar (265.0 kPa); however, 
fusible elements are authorized on portable tanks for the transportation 
of certain organometallic materials in accordance with Sec. 172.102, 
special provision TP36 of this subchapter. Fusible elements used on 
portable tanks intended for the transport of elevated temperature 
hazardous materials

[[Page 120]]

must be designed to operate at a temperature higher than the maximum 
temperature that will be experienced during transport and must be 
designed to the satisfaction of the approval agency.
    (i) Capacity of pressure relief devices. (1) The reclosing pressure 
relief device required by paragraph (g)(1) of this section must have a 
minimum cross sectional flow area equivalent to an orifice of 31.75 mm 
(1.3 inches) diameter. Vacuum-relief devices, when used, must have a 
cross sectional flow area not less than 284 mm \2\ (11.2 inches \2\).
    (2) The combined delivery capacity of the pressure relief system 
(taking into account the reduction of the flow when the portable tank is 
fitted with frangible-discs preceding spring-loaded pressure-relief 
devices or when the spring-loaded pressure-relief devices are provided 
with a device to prevent the passage of the flame), in condition of 
complete fire engulfment of the portable tank must be sufficient to 
limit the pressure in the shell to 20% above the start to discharge 
pressure limiting device (pressure relief device). The total required 
capacity of the relief devices may be determined using the formula in 
paragraph (i)(2)(i)(A) of this section or the table in paragraph 
(i)(2)(iii) of this section.
    (i)(A) To determine the total required capacity of the relief 
devices, which must be regarded as being the sum of the individual 
capacities of all the contributing devices, the following formula must 
be used:
[GRAPHIC] [TIFF OMITTED] TR01OC08.000

Where:

Q = minimum required rate of discharge in cubic meters of air per second 
          (m\3\/s) at conditions: 1 bar and 0 [deg]C (273 [deg]K);
F = for uninsulated shells: 1; for insulated shells: U(649-t)/13.6 but 
          in no case is less than 0.25
Where:

U = thermal conductance of the insulation, in kW 
          m-2K-1, at 38 [deg]C (100 [deg]F); and t 
          = actual temperature of the hazardous material during filling 
          (in [deg]C) or when this temperature is unknown, let t = 15 
          [deg]C (59 [deg]F). The value of F given in this paragraph 
          (i)(2)(i)(A) for insulated shells may only be used if the 
          insulation is in conformance with paragraph (i)(2)(iv) of this 
          section;
A = total external surface area of shell in square meters;
Z = the gas compressibility factor in the accumulating condition (when 
          this factor is unknown, let Z equal 1.0);
T = absolute temperature in Kelvin ([deg]C+273) above the pressure 
          relief devices in the accumulating condition;
L = the latent heat of vaporization of the liquid, in kJ/kg, in the 
          accumulating condition;
M = molecular weight of the hazardous material.

    (B) The constant C, as shown in the formula in paragraph 
(i)(2)(i)(A) of this section, is derived from one of the following 
formulas as a function of the ratio k of specific heats:
[GRAPHIC] [TIFF OMITTED] TR01OC08.001

Where:

cp is the specific heat at constant pressure; and
cv is the specific heat at constant volume.

    (C) When k 1:
    [GRAPHIC] [TIFF OMITTED] TR01OC08.002
    
    (D) When k = 1 or k is unknown, a value of 0.607 may be used for the 
constant C. C may also be taken from the following table:

                         C Constant Value Table
------------------------------------------------------------------------
                 k                                    C
------------------------------------------------------------------------
                   1.00                                0.607
                   1.02                                0.611
                   1.04                                0.615
                   1.06                                0.620
                   1.08                                0.624
                   1.10                                0.628
                   1.12                                0.633
                   1.14                                0.637
                   1.16                                0.641
                   1.18                                0.645
                   1.20                                0.649
                   1.22                                0.652
                   1.24                                0.656
                   1.26                                0.660
                   1.28                                0.664
                   1.30                                0.667
                   1.32                                0.671
                   1.34                                0.674
                   1.36                                0.678
                   1.38                                0.681
                   1.40                                0.685
                   1.42                                0.688
                   1.44                                0.691

[[Page 121]]

 
                   1.46                                0.695
                   1.48                                0.698
                   1.50                                0.701
                   1.52                                0.704
                   1.54                                0.707
                   1.56                                0.710
                   1.58                                0.713
                   1.60                                0.716
                   1.62                                0.719
                   1.64                                0.722
                   1.66                                0.725
                   1.68                                0.728
                   1.70                                0.731
                   2.00                                0.770
                   2.20                                0.793
 
------------------------------------------------------------------------

    (ii) As an alternative to the formula in paragraph (i)(2)(i)(A) of 
this section, relief devices for shells used for transporting liquids 
may be sized in accordance with the table in paragraph (i)(2)(iii) of 
this section. The table in paragraph (i)(2)(iii) of this section assumes 
an insulation value of F = 1 and must be adjusted accordingly when the 
shell is insulated. Other values used in determining the table in 
paragraph (i)(2)(iii) of this section are: L = 334.94 kJ/kg; M = 86.7; T 
= 394 [deg]K; Z = 1; and C = 0.607.
    (iii) Minimum emergency vent capacity, Q, in cubic meters of air per 
second at 1 bar and 0 [deg]C (273 [deg]K) shown in the following table:

                     Minimum Emergency Vent Capacity
                               [Q Values]
------------------------------------------------------------------------
                    Q (Cubic meters                      Q (Cubic meters
  A Exposed area       of air per      A Exposed area      of air per
 (square meters)        second)        (square meters)       second)
------------------------------------------------------------------------
          2              0.230               37.5             2.539
          3              0.320                 40             2.677
          4              0.405               42.5             2.814
          5              0.487                 45             2.949
          6              0.565               47.5             3.082
          7              0.641                 50             3.215
          8              0.715               52.5             3.346
          9              0.788                 55             3.476
         10              0.859               57.5             3.605
         12              0.998                 60             3.733
         14              1.132               62.5             3.860
         16              1.263                 65             3.987
         18              1.391               67.5             4.112
         20              1.517                 70             4.236
       22.5              1.670                 75             4.483
         25              1.821                 80             4.726
       27.5              1.969                 85             4.967
         30              2.115                 90             5.206
       32.5              2.258                 95             5.442
         35              2.400                100             5.676
------------------------------------------------------------------------

    (iv) Insulation systems, used for the purpose of reducing venting 
capacity, must be specifically approved by the approval agency. In all 
cases, insulation systems approved for this purpose must--
    (A) Remain effective at all temperatures up to 649 [deg]C (1200 
[deg]F); and
    (B) Be jacketed with a material having a melting point of 700 [deg]C 
(1292 [deg]F) or greater.
    (j) Approval, inspection and testing. Approval procedures for UN 
portable tanks are specified in Sec. 178.273. Inspection and testing 
requirements are specified in Sec. 180.605 of this subchapter.

[66 FR 33445, June 21, 2001, as amended at 68 FR 32414, May 30, 2003; 69 
FR 76185, Dec. 20, 2004; 73 FR 57006, Oct. 1, 2008; 76 FR 3388, Jan. 19, 
2011]



Sec. 178.276  Requirements for the design, construction, inspection 
and testing of portable tanks intended for the transportation of non-
refrigerated liquefied compressed gases.

    (a) In addition to the requirements of Sec. 178.274 applicable to 
UN portable tanks, the following requirements apply to UN portable tanks 
used for non-refrigerated liquefied compressed gases. In addition to the 
definitions in Sec. 178.274, the following definitions apply:
    (1) Design pressure means the pressure to be used in calculations 
required by the ASME Code, Section VIII (IBR, see Sec. 171.7 of this 
subchapter). The design pressure must be not less than the highest of 
the following pressures:
    (i) The maximum effective gauge pressure allowed in the shell during 
filling or discharge; or
    (ii) The sum of:
    (A) The maximum effective gauge pressure to which the shell is 
designed as defined in this paragraph under ``MAWP''; and
    (B) A head pressure determined on the basis of the dynamic forces 
specified in paragraph (h) of this section, but not less than 0.35 bar 
(35 kPa).
    (2) Design reference temperature means the temperature at which the 
vapor pressure of the contents is determined for the purpose of 
calculating the MAWP. The value for each portable tank type is as 
follows:
    (i) Shell with a diameter of 1.5 meters (4.9 ft.) or less: 65 [deg]C 
(149 [deg]F); or

[[Page 122]]

    (ii) Shell with a diameter of more than 1.5 meters (4.9 ft.):
    (A) Without insulation or sun shield: 60 [deg]C (140 [deg]F);
    (B) With sun shield: 55 [deg]C (131 [deg]F); and
    (C) With insulation: 50 [deg]C (122 [deg]F).
    (3) Filling density means the average mass of liquefied compressed 
gas per liter of shell capacity (kg/l).
    (4) Maximum allowable working pressure (MAWP) means a pressure that 
must be not less than the highest of the following pressures measured at 
the top of the shell while in operating position, but in no case less 
than 7 bar (700 kPa):
    (i) The maximum effective gauge pressure allowed in the shell during 
filling or discharge; or
    (ii) The maximum effective gauge pressure to which the shell is 
designed, which must be:
    (A) Not less than the pressure specified for each liquefied 
compressed gas listed in the UN Portable Tank Table for Liquefied 
Compressed Gases in Sec. 173.313; and
    (B) Not less than the sum of:
    (1) The absolute vapor pressure (in bar) of the liquefied compressed 
gas at the design reference temperature minus 1 bar; and
    (2) The partial pressure (in bar) of air or other gases in the 
ullage space which is determined by the design reference temperature and 
the liquid phase expansion due to the increase of the mean bulk 
temperature of tr-tf (tf = filling 
temperature, usually 15 [deg]C, tr = 50 [deg]C maximum mean 
bulk temperature).
    (b) General design and construction requirements. (1) Shells must be 
of seamless or welded steel construction, or combination of both, and 
have a water capacity greater than 450 liters (118.9 gallons). Shells 
must be designed, constructed, certified and stamped in accordance with 
the ASME Code, Section VIII.
    (2) Portable tanks must be postweld heat-treated and radiographed as 
prescribed in Section VIII of the ASME Code, except that each portable 
tank constructed in accordance with part UHT of the ASME Code must be 
postweld heat-treated. Where postweld heat treatment is required, the 
portable tank must be treated as a unit after completion of all the 
welds in and/or to the shell and heads. The method must be as prescribed 
in the ASME Code. Welded attachments to pads may be made after postweld 
heat treatment is made. A portable tank used for anhydrous ammonia must 
be postweld heat-treated. The postweld heat treatment must be as 
prescribed in the ASME Code, but in no event at less than 1050 [deg]F 
tank metal temperature. Additionally, portable tanks constructed in 
accordance with part UHT of the ASME Code must conform to the following 
requirements:
    (i) Welding procedure and welder performance tests must be made 
annually in accordance with Section IX of the ASME Code. In addition to 
the essential variables named therein, the following must be considered 
to be essential variables: number of passes, thickness of plate, heat 
input per pass, and manufacturer's identification of rod and flux. The 
number of passes, thickness of plate and heat input per pass may not 
vary more than 25 percent from the qualified procedure. Records of the 
qualification must be retained for at least 5 years by the portable tank 
manufacturer or his designated agent and, upon request, made available 
to a representative of the Department of Transportation or the owner of 
the tank.
    (ii) Impact tests must be made on a lot basis. A lot is defined as 
100 tons or less of the same heat and having a thickness variation no 
greater than plus or minus 25 percent. The minimum impact required for 
full-sized specimens shall be 20 foot-pounds (or 10 foot-pounds for 
half-sized specimens) at 0 [deg]F (-17.8 [deg]F) Charpy V-Notch in both 
the longitudinal and transverse direction. If the lot test does not pass 
this requirement, individual plates may be accepted if they individually 
meet this impact requirement.
    (3) When the shells intended for the transportation of non-
refrigerated liquefied compressed gases are equipped with thermal 
insulation, a device must be provided to prevent any dangerous pressure 
from developing in the insulating layer in the event of a leak, when the 
protective covering is closed it must be gas tight. The thermal 
insulation must not inhibit access to the

[[Page 123]]

fittings and discharge devices. In addition, the thermal insulation 
systems must satisfy the following requirements:
    (i) consist of a shield covering not less than the upper third, but 
not more than the upper half of the surface of the shell, and separated 
from the shell by an air space of approximately 40 mm (1.7 inches) 
across; or
    (ii) consist of a complete cladding of insulating materials. The 
insulation must be of adequate thickness and constructed to prevent the 
ingress of moisture and damage to the insulation. The insulation and 
cladding must have a thermal conductance of not more than 0.67 
(W[middot]m-2[middot]K-1) under normal conditions 
of transportation.
    (c) Service equipment. (1) Each opening with a diameter of more than 
1.5 mm (0.1 inch) in the shell of a portable tank, except openings for 
pressure-relief devices, inspection openings and closed bleed holes, 
must be fitted with at least three mutually independent shut-off devices 
in series: the first being an internal stop-valve, excess flow valve, 
integral excess flow valve, or excess flow feature (see Sec. 178.337-
1(g)), the second being an external stop-valve and the third being a 
blank flange, thread cap, plug or equivalent tight liquid closure 
device.
    (2) When a portable tank is fitted with an excess flow valve, the 
excess flow valve must be so fitted that its seating is inside the shell 
or inside a welded flange or, when fitted externally, its mountings must 
be designed so that in the event of impact it maintains its 
effectiveness. The excess flow valves must be selected and fitted so as 
to close automatically when the rated flow, specified by the 
manufacturer, is reached. Connections and accessories leading to or from 
such a valve must have a capacity for a flow more than the excess flow 
valve's rated flow.
    (3) For filling and discharge openings that are located below the 
liquid level, the first shut-off device must be an internal stop-valve 
and the second must be a stop-valve placed in an accessible position on 
each discharge and filling pipe.
    (4) For filling and discharge openings located below the liquid 
level of portable tanks intended for the transportation of flammable 
and/or toxic liquefied compressed gases, the internal stop-valve must be 
a self-closing safety device that fully closes automatically during 
filling or discharge in the event of fire engulfment. The device shall 
fully close within 30 seconds of actuation and the thermal means of 
closure must actuate at a temperature of not more than 121 [deg]C (250 
[deg]F). Except for portable tanks having a capacity less than 1,000 
liters (264.2 gallons), this device must be operable by remote control.
    (5) In addition to filling, discharge and gas pressure equalizing 
orifices, shells may have openings in which gauges, thermometers and 
manometers can be fitted. Connections for such instruments must be made 
by suitable welded nozzles or pockets and may not be connected by 
screwed connections through the shell.
    (6) All portable tanks must be fitted with manholes or other 
inspection openings of suitable size to allow for internal inspection 
and adequate access for maintenance and repair of the interior.
    (7) Inlets and discharge outlets on chlorine portable tanks. The 
inlet and discharge outlets on portable tanks used to transport chlorine 
must meet the requirements of Sec. 178.337-1(c)(2) and must be fitted 
with an internal excess flow valve. In addition to the internal excess 
flow valve, the inlet and discharge outlets must be equipped with an 
external stop valve (angle valve). Excess flow valves must conform to 
the standards of The Chlorine Institute, Inc. (IBR, see Sec. 171.7 of 
this subchapter) as follows:
    (i) A valve conforming to Drawing 101-7, dated July 1993, must be 
installed under each liquid angle valve.
    (ii) A valve conforming to Drawing 106-6, dated July 1993, must be 
installed under each gas angle valve. For portable tanks used to 
transport non-refrigerated liquefied gases.
    (8) External fittings must be grouped together as close as 
reasonably practicable. The following openings may be installed at 
locations other than on the top or end of the tank:
    (i) The openings for liquid level gauging devices, pressure gauges, 
or for

[[Page 124]]

safety devices, may be installed separately at the other location or in 
the side of the shell;
    (ii) One plugged opening of 2-inch National Pipe Thread or less 
provided for maintenance purposes may be located elsewhere;
    (iii) An opening of 3-inch National Pipe Size or less may be 
provided at another location, when necessary, to facilitate installation 
of condensing coils.
    (9) Filling and discharge connections are not required to be grouped 
and may be installed below the normal liquid level of the tank if:
    (i) The portable tank is permanently mounted in a full framework for 
containerized transport;
    (ii) For each portable tank design, a prototype portable tank, meets 
the requirements of parts 450 through 453 of this title for compliance 
with the requirements of Annex II of the International Convention for 
Safe Containers; and
    (iii) Each filling and discharge outlet meets the requirements of 
paragraph (c)(4) of this section.
    (d) Bottom openings. Bottom openings are prohibited on portable 
tanks when the UN Portable Tank Table for Liquefied Compressed Gases in 
Sec. 173.313 of this subchapter indicates that bottom openings are not 
allowed. In this case, there may be no openings located below the liquid 
level of the shell when it is filled to its maximum permissible filling 
limit.
    (e) Pressure relief devices. (1) Portable tanks must be provided 
with one or more reclosing pressure relief devices. The pressure relief 
devices must open automatically at a pressure not less than the MAWP and 
be fully open at a pressure equal to 110% of the MAWP. These devices 
must, after discharge, close at a pressure not less than 10% below the 
pressure at which discharge starts and must remain closed at all lower 
pressures. The pressure relief devices must be of a type that will 
resist dynamic forces including liquid surge. A frangible disc may only 
be used in series with a reclosing pressure relief device.
    (2) Pressure relief devices must be designed to prevent the entry of 
foreign matter, the leakage of gas and the development of any dangerous 
excess pressure.
    (3) A portable tank intended for the transportation of certain 
liquefied compressed gases identified in the UN Portable Tank Table for 
Liquefied Compressed Gases in Sec. 173.313 of this subchapter must have 
a pressure relief device which conforms to the requirements of this 
subchapter. Unless a portable tank, in dedicated service, is fitted with 
a relief device constructed of materials compatible with the hazardous 
material, the relief device must be comprised of a frangible disc 
preceded by a reclosing device. The space between the frangible disc and 
the device must be provided with a pressure gauge or a suitable tell-
tale indicator. This arrangement must facilitate the detection of disc 
rupture, pinholing or leakage which could cause a malfunction of the 
pressure relief device. The frangible disc must rupture at a nominal 
pressure 10% above the start-to-discharge pressure of the relief device.
    (4) In the case of portable tanks used for more than one gas, the 
pressure relief devices must open at a pressure indicated in paragraph 
(e)(1) of this section for the gas having the highest maximum allowable 
pressure of the gases allowed to be transported in the portable tank.
    (f) Capacity of relief devices. The combined delivery capacity of 
the relief devices must be sufficient so that, in the event of total 
fire engulfment, the pressure inside the shell cannot exceed 120% of the 
MAWP. Reclosing relief devices must be used to achieve the full relief 
capacity prescribed. In the case of portable tanks used for more than 
gas, the combined delivery capacity of the pressure relief devices must 
be taken for the liquefied compressed gas which requires the highest 
delivery capacity of the liquefied compressed gases allowed to be 
transported in the portable tank. The total required capacity of the 
relief devices must be determined according to the requirements in Sec. 
178.275(i). These requirements apply only to liquefied compressed gases 
which have critical temperatures well above the temperature at the 
accumulating condition. For gases that have critical temperatures near 
or below the temperature at the

[[Page 125]]

accumulating condition, the calculation of the pressure relief device 
delivery capacity must consider the additional thermodynamic properties 
of the gas, for example see CGA S-1.2 (IBR, see Sec. 171.7 of this 
subchapter).

[66 FR 33448, June 21, 2001, as amended at 68 FR 75748, 75752, Dec. 31, 
2003; 69 FR 54046, Sept. 7, 2004; 69 FR 76185, Dec. 20, 2004]



Sec. 178.277  Requirements for the design, construction, inspection 
and testing of portable tanks intended for the transportation of 
refrigerated liquefied gases.

    (a) In addition to the requirements of Sec. 178.274 applicable to 
UN portable tanks, the following requirements and definitions apply to 
UN portable tanks used for refrigerated liquefied gases:
    Design pressure For the purpose of this section the term ``design 
pressure'' is consistent with the definition for design pressure in the 
ASME Code, Section VIII (IBR, see Sec. 171.7 of this subchapter).
    Holding time is the time, as determined by testing, that will elapse 
from loading until the pressure of the contents, under equilibrium 
conditions, reaches the lowest set pressure of the pressure limiting 
device(s) (for example, pressure control valve or pressure relief 
device). Holding time must be determined as specified in Sec. 178.338-
9.
    Maximum allowable working pressure (MAWP) means the maximum 
effective gauge pressure permissible at the top of the shell of a loaded 
portable tank in its operating position including the highest effective 
pressure during filling and discharge;
    Minimum design temperature means the temperature which is used for 
the design and construction of the shell not higher than the lowest 
(coldest) service temperature of the contents during normal conditions 
of filling, discharge and transportation.
    Shell means the part of the portable tank which retains the 
refrigerated liquefied gas intended for transport, including openings 
and their closures, but does not include service equipment or external 
structural equipment.
    Tank means a construction which normally consists of either:
    (1) A jacket and one or more inner shells where the space between 
the shell(s) and the jacket is exhausted of air (vacuum insulation) and 
may incorporate a thermal insulation system; or
    (2) A jacket and an inner shell with an intermediate layer of solid 
thermally insulating material (for example, solid foam).
    (b) General design and construction requirements. (1) Portable tanks 
must be of seamless or welded steel construction and have a water 
capacity of more than 450 liters (118.9 gallons). Portable tanks must be 
designed, constructed, certified and stamped in accordance with Section 
VIII of the ASME Code.
    (2) Portable tanks must be postweld heat treated and radiographed as 
prescribed in Sections V and VIII of the ASME Code except that each tank 
constructed in accordance with part UHT in Section VIII of the ASME Code 
must be postweld heat treated. Where postweld heat treatment is 
required, the tank must be treated as a unit after completion of all the 
welds to the shell and heads. The method must be as prescribed in the 
ASME Code. Welded attachments to pads may be made after postweld heat 
treatment is made. The postweld heat treatment must be as prescribed in 
Section VIII of the ASME Code, but in no event at less than 1,050 [deg]F 
tank metal temperature.
    (3) Welding procedure and welder performance tests must be made 
annually in accordance with Section IX of the ASME Code (IBR, see Sec. 
171.7 of this subchapter). In addition to the essential variables named 
in the ASME Code, the following must be considered as essential 
variables: number of passes, thickness of plate, heat input per pass, 
and the specified rod and flux. The number of passes, thickness of plate 
and heat input per pass may not vary more than 25% from the procedure 
qualification. Records of the qualification must be retained for at 
least 5 years by the portable tank manufacturer and made available to 
the approval agency and the owner of the portable tank as specified in 
Sec. 178.273.
    (4) Shells and jackets must be made of metallic materials suitable 
for forming. Jackets must be made of steel. Non-metallic materials may 
be used for the attachments and supports between the shell and jacket, 
provided

[[Page 126]]

their material properties at the minimum design temperature are proven 
to be sufficient. In choosing the material, the minimum design 
temperature must be taken into account with respect to risk of brittle 
fracture, to hydrogen embrittlement, to stress corrosion cracking and to 
resistance to impact.
    (5) Any part of a portable tank, including fittings, gaskets and 
pipe-work, which can be expected normally to come into contact with the 
refrigerated liquefied gas transported must be compatible with that 
refrigerated liquefied gas.
    (6) The thermal insulation system must include a complete covering 
of the shell with effective insulating materials. External insulation 
must be protected by a jacket so as to prevent the ingress of moisture 
and other damage under normal transport conditions.
    (7) When a jacket is so closed as to be gas-tight, a device must be 
provided to prevent any dangerous pressure from developing in the 
insulation space.
    (8) Materials which may react with oxygen or oxygen enriched 
atmospheres in a dangerous manner may not be used in portable tanks 
intended for the transport of refrigerated liquefied gases having a 
boiling point below minus 182 [deg]C at atmospheric pressure in 
locations with the thermal insulation where there is a risk of contact 
with oxygen or with oxygen enriched fluid.
    (9) Insulating materials must not deteriorate to an extent that the 
effectiveness of the insulation system, as determined in accordance with 
paragraph (b)(11) of this section, would be reduced in service.
    (10) A reference holding time must be determined for each 
refrigerated liquefied gas intended for transport in a portable tank. 
The reference holding time must be determined by testing in accordance 
with the requirements of Sec. 178.338-9, considering the following 
factors:
    (i) The effectiveness of the insulation system, determined in 
accordance with paragraph (b)(11) of this section;
    (ii) The lowest set pressure of the pressure limiting device;
    (iii) The initial filling conditions;
    (iv) An assumed ambient temperature of 30 [deg]C (86 [deg]F);
    (v) The physical properties of the individual refrigerated liquefied 
gas intended to be transported.
    (11) The effectiveness of the insulation system (heat influx in 
watts) may be determined by type testing the portable tank in accordance 
with a procedure specified in Sec. 178.338-9(c) or by using the holding 
time test in Sec. 178.338-9(b). This test must consist of either:
    (i) A constant pressure test (for example, at atmospheric pressure) 
when the loss of refrigerated liquefied gas is measured over a period of 
time; or
    (ii) A closed system test when the rise in pressure in the shell is 
measured over a period of time.
    (12) When performing the constant pressure test, variations in 
atmospheric pressure must be taken into account. When performing either 
test, corrections must be made for any variation of the ambient 
temperature from the assumed ambient temperature reference value of 30 
[deg]C (86 [deg]F).
    (13) The jacket of a vacuum-insulated double-wall tank must have 
either an external design pressure not less than 100 kPa (1 bar) gauge 
pressure calculated in accordance with Section VIII of the ASME Code or 
a calculated critical collapsing pressure of not less than 200 kPa (2 
bar) gauge pressure. Internal and external reinforcements may be 
included in calculating the ability of the jacket to resist the external 
pressure.

    Note to paragraph (b): For the determination of the actual holding 
time, as indicated by paragraphs (b)(10), (11), (12), and (13), before 
each journey, refer to Sec. 178.338-9(b).

    (c) Design criteria. For shells with vacuum insulation, the test 
pressure must not be less than 1.3 times the sum of the MAWP and 100 kPa 
(1 bar). In no case may the test pressure be less than 300 kPa (3 bar) 
gauge pressure.
    (d) Service equipment. (1) Each filling and discharge opening in 
portable tanks used for the transport of flammable refrigerated 
liquefied gases must be fitted with at least three mutually independent 
shut-off devices in series: the first being a stop-valve situated as 
close as reasonably practicable to the jacket, the second being a stop-
valve

[[Page 127]]

and the third being a blank flange or equivalent device. The shut-off 
device closest to the jacket must be a self-closing device, which is 
capable of being closed from an accessible position on the portable tank 
that is remote from the valve within 30 seconds of actuation. This 
device must actuate at a temperature of not more than 121 [deg]C (250 
[deg]F).
    (2) Each filling and discharge opening in portable tanks used for 
the transport of non-flammable refrigerated liquefied gases must be 
fitted with at least two mutually independent shut-off devices in 
series: the first being a stop-valve situated as close as reasonably 
practicable to the jacket and the second a blank flange or equivalent 
device.
    (3) For sections of piping which can be closed at both ends and 
where liquid product can be trapped, a method of automatic pressure 
relief must be provided to prevent excess pressure build-up within the 
piping.
    (4) Each filling and discharge opening on a portable tank must be 
clearly marked to indicate its function.
    (5) When pressure-building units are used, the liquid and vapor 
connections to that unit must be provided with a valve as close to the 
jacket as reasonably practicable to prevent the loss of contents in case 
of damage to the pressure-building unit. A check valve may be used for 
this purpose if it is located on the vapor side of the pressure build-up 
coil.
    (6) The materials of construction of valves and accessories must 
have satisfactory properties at the lowest operating temperature of the 
portable tank.
    (7) Vacuum insulated portable tanks are not required to have an 
inspection opening.
    (e) Pressure relief devices. (1) Every shell must be provided with 
not less than two independent reclosing pressure relief devices. The 
pressure relief devices must open automatically at a pressure not less 
than the MAWP and be fully open at a pressure equal to 110% of the MAWP. 
These devices must, after discharge, close at a pressure not lower than 
10% below the pressure at which discharge starts and must remain closed 
at all lower pressures. The pressure relief devices must be of the type 
that will resist dynamic forces including surge.
    (2) Except for portable tanks used for oxygen, portable tanks for 
non-flammable refrigerated liquefied gases (except oxygen) and hydrogen 
may in addition have frangible discs in parallel with the reclosing 
devices as specified in paragraphs (e)(4)(ii) and (e)(4)(iii) of this 
section.
    (3) Pressure relief devices must be designed to prevent the entry of 
foreign matter, the leakage of gas and the development of any dangerous 
excess pressure.
    (4) Capacity and setting of pressure relief devices. (i) In the case 
of the loss of vacuum in a vacuum-insulated tank or of loss of 20% of 
the insulation of a portable tank insulated with solid materials, the 
combined capacity of all pressure relief devices installed must be 
sufficient so that the pressure (including accumulation) inside the 
shell does not exceed 120% of the MAWP.
    (ii) For non-flammable refrigerated liquefied gases (except oxygen) 
and hydrogen, this capacity may be achieved by the use of frangible 
discs in parallel with the required safety-relief devices. Frangible 
discs must rupture at nominal pressure equal to the test pressure of the 
shell.
    (iii) Under the circumstances described in paragraphs (e)(4)(i) and 
(e)(4)(ii) of this section, together with complete fire engulfment, the 
combined capacity of all pressure relief devices installed must be 
sufficient to limit the pressure in the shell to the test pressure.
    (iv) The required capacity of the relief devices must be calculated 
in accordance with CGA Pamphlet S-1.2 (IBR, see Sec. 171.7 of this 
subchapter).

[66 FR 33450, June 21, 2001, as amended at 68 FR 75748, 75752, Dec. 31, 
2003]

Subpart I [Reserved]



Subpart J_Specifications for Containers for Motor Vehicle Transportation

    Source: 29 FR 18975, Dec. 29, 1964, unless otherwise noted. 
Redesignated at 32 FR 5606, Apr. 5, 1967.

[[Page 128]]



Sec. 178.318  Specification MC 201; container for detonators and 
percussion caps.



Sec. 178.318-1  Scope.

    (a) This specification pertains to a container to be used for the 
transportation of detonators and percussion caps in connection with the 
transportation of liquid nitroglycerin, desensitized liquid 
nitroglycerin or diethylene glycol dinitrate, where any or all of such 
types of caps may be used for the detonation of liquid nitroglycerin, 
desentitized liquid nitroglycerin or diethylene glycol dinitrate in 
blasting operations. This specification is not intended to take the 
place of any shipping or packing requirements of this Department where 
the caps in question are themselves articles of commerce.
    (b) [Reserved]

[29 FR 18975, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 178-60, 44 FR 70733, Dec. 10, 1979]



Sec. 178.318-2  Container.

    (a) Every container for detonators and percussion caps coming within 
the scope of this specification shall be constructed entirely of hard 
rubber, phenolresinous or other resinous material, or other nonmetallic, 
nonsparking material, except that metal parts may be used in such 
locations as not in any event to come in contact with any of the caps. 
Space shall be provided so that each detonator of whatever nature may be 
inserted in an individual cell in the body of the container, into which 
each such cap shall snugly fit. There shall be provided no more than 
twenty (20) such cellular spaces. Space may be provided into which a 
plurality of percussion caps may be carried, provided that such space 
may be closed with a screw cap, and further provided that each or any 
such space is entirely separate from any space provided for any 
detonator. Each cellular space into which a detonator is to be inserted 
and carried shall be capable of being covered by a rotary cover so 
arranged as to expose not more than one cell at any time, and capable of 
rotation to such a place that all cells will be covered at the same 
time, at which place means shall be provided to lock the cover in place. 
Means shall be provided to lock in place the cover for the cells 
provided for the carrying of detonators. The requirement that not more 
than one cell be exposed at one time need not apply in the case of 
detonators, although spaces for such caps and detonators shall be 
separate. Sufficient annular space shall be provided inside the cover 
for such detonators that, when the cover is closed, there will be 
sufficient space to accommodate the wires customarily attached to such 
caps. If the material is of such a nature as to require treatment to 
prevent the absorption of moisture, such treatment shall be applied as 
shall be necessary in order to provide against the penetration of water 
by permeation. A suitable carrying handle shall be provided, except for 
which handle no part of the container may project beyond the exterior of 
the body.
    (b) Exhibited in plates I and II are line drawings of a container 
for detonators and percussion caps, illustrative of the requirements set 
forth in Sec. 178.318-2(a). These plates shall not be construed as a 
part of this specification.

[[Page 129]]

[GRAPHIC] [TIFF OMITTED] TC02MR91.076



Sec. 178.318-3  Marking.

    Each container must be marked as prescribed in Sec. 178.2(b).

[Amdt. 178-40, 41 FR 38181, Sept. 9, 1976, as amended at 66 FR 45185, 
Aug. 28, 2001]



Sec. 178.320  General requirements applicable to all DOT specification
cargo tank motor vehicles.

    (a) Definitions. For the purpose of this subchapter:
    Appurtenance means any attachment to a cargo tank that has no lading 
retention or containment function and provides no structural support to 
the cargo tank.
    Baffle means a non-liquid-tight transverse partition device that 
deflects, checks or regulates fluid motion in a tank.
    Bulkhead means a liquid-tight transverse closure at the ends of or 
between cargo tanks.
    Cargo tank means a bulk packaging that:
    (1) Is a tank intended primarily for the carriage of liquids, gases, 
solids, or

[[Page 130]]

semi-solids and includes appurtenances, reinforcements, fittings, and 
closures (for tank, see Sec. Sec. 178.337-1, 178.338-1, or 178.345-1, 
as applicable);
    (2) Is permanently attached to or forms a part of a motor vehicle, 
or is not permanently attached to a motor vehicle but that, by reason of 
its size, construction, or attachment to a motor vehicle, is loaded or 
unloaded without being removed from the motor vehicle; and
    (3) Is not fabricated under a specification for cylinders, 
intermediate bulk containers, multi-unit tank car tanks, portable tanks, 
or tank cars.
    Cargo tank motor vehicle means a motor vehicle with one or more 
cargo tanks permanently attached to or forming an integral part of the 
motor vehicle.
    Cargo tank wall means those parts of the cargo tank that make up the 
primary lading retention structure, including shell, bulkheads, and 
fittings and, when closed, yield the minimum volume of a completed cargo 
tank motor vehicle.
    Charging line means a hose, tube, pipe, or a similar device used to 
pressurize a tank with material other than the lading.
    Companion flange means one of two mating flanges where the flange 
faces are in contact or separated only by a thin leak-sealing gasket and 
are secured to one another by bolts or clamps.
    Connecting structure means the structure joining two cargo tanks.
    Constructed and certified in accordance with the ASME Code means a 
cargo tank is constructed and stamped in accordance with Section VIII of 
the ASME Code (IBR, see Sec. 171.7 of this subchapter), and is 
inspected and certified by an Authorized Inspector.
    Constructed in accordance with the ASME Code means a cargo tank is 
constructed in accordance with Section VIII of the ASME Code with 
authorized exceptions (see Sec. Sec. 178.346 through 178.348) and is 
inspected and certified by a Registered Inspector.
    Design type means one or more cargo tanks that are made--
    (1) To the same specification;
    (2) By the same manufacturer;
    (3) To the same engineering drawings and calculations, except for 
minor variations in piping that do not affect the lading retention 
capability of the cargo tank;
    (4) Of the same materials of construction;
    (5) To the same cross-sectional dimensions;
    (6) To a length varying by no more than 5 percent;
    (7) With the volume varying by no more than 5 percent (due to a 
change in length only); and
    (8) For the purposes of Sec. 178.338 only, with the same insulation 
system.
    External self-closing stop valve means a self-closing stop valve 
designed so that the self-stored energy source is located outside the 
cargo tank and the welded flange.
    Extreme dynamic loading means the maximum loading a cargo tank motor 
vehicle may experience during its expected life, excluding accident 
loadings resulting from an accident, such as overturn or collision.
    Flange means the structural ring for guiding or attachment of a pipe 
or fitting with another flange (companion flange), pipe, fitting or 
other attachment.
    Inspection pressure means the pressure used to determine leak 
tightness of the cargo tank when testing with pneumatic pressure.
    Internal self-closing stop valve means a self-closing stop valve 
designed so that the self-stored energy source is located inside the 
cargo tank or cargo tank sump, or within the welded flange, and the 
valve seat is located within the cargo tank or within one inch of the 
external face of the welded flange or sump of the cargo tank.
    Lading means the hazardous material contained in a cargo tank.
    Loading/unloading connection means the fitting in the loading/
unloading line farthest from the loading/unloading outlet to which the 
loading/unloading hose, pipe, or device is attached.
    Loading/unloading outlet means a cargo tank outlet used for normal 
loading/unloading operations.
    Loading/unloading stop valve means the stop valve farthest from the 
cargo tank loading/unloading outlet to which

[[Page 131]]

the loading/unloading connection is attached.
    Manufacturer means any person engaged in the manufacture of a DOT 
specification cargo tank, cargo tank motor vehicle, or cargo tank 
equipment that forms part of the cargo tank wall. This term includes 
attaching a cargo tank to a motor vehicle or to a motor vehicle 
suspension component that involves welding on the cargo tank wall. A 
manufacturer must register with the Department in accordance with 
subpart F of part 107 in subpart A of this chapter.
    Maximum allowable working pressure or MAWP means the maximum 
pressure allowed at the top of the tank in its normal operating 
position. The MAWP must be calculated as prescribed in Section VIII of 
the ASME Code. In use, the MAWP must be greater than or equal to the 
maximum lading pressure conditions prescribed in Sec. 173.33 of this 
subchapter for each material transported.
    Maximum lading pressure. See Sec. 173.33(c).
    Minimum thickness means the minimum required shell and head (and 
baffle and bulkhead when used as tank reinforcement) thickness needed to 
meet the specification. The minimum thickness is the greatest of the 
following values: (1)(i) For MC 330, MC 331, and MC 338 cargo tanks, the 
specified minimum thickness found the applicable specification(s); or
    (ii) For DOT 406, DOT 407 and DOT 412 cargo tanks, the specified 
minimum thickness found in Tables I and II of the applicable 
specification(s); or
    (iii) For MC 300, MC 301, MC 302, MC 303, MC 304, MC 305, MC 306, MC 
307, MC 310, MC 311, and MC 312 cargo tanks, the in-service minimum 
thickness prescribed in Tables I and II of Sec. 180.407(i)(5) of this 
subchapter, for the minimum thickness specified by Tables I and II of 
the applicable specification(s); or
    (2) The thickness necessary to meet with the structural integrity 
and accident damage requirements of the applicable specification(s); or
    (3) The thickness as computed per the ASME Code requirements (if 
applicable).
    Multi-specification cargo tank motor vehicle means a cargo tank 
motor vehicle equipped with two or more cargo tanks fabricated to more 
than one cargo tank specification.
    Normal operating loading means the loading a cargo tank motor 
vehicle may be expected to experience routinely in operation.
    Nozzle means a subassembly consisting of a pipe or tubular section 
with or without a welded or forged flange on one end.
    Outlet means any opening in the shell or head of a cargo tank, 
(including the means for attaching a closure), except that the following 
are not outlets: a threaded opening securely closed during 
transportation with a threaded plug or a threaded cap, a flanged opening 
securely closed during transportation with a bolted or welded blank 
flange, a manhole, a gauging device, a thermometer well, or a pressure 
relief device.
    Outlet stop valve means the stop valve at a cargo tank loading or 
unloading outlet.
    Pipe coupling means a fitting with internal threads on both ends.
    Rear bumper means the structure designed to prevent a vehicle or 
object from under-riding the rear of another motor vehicle. See Sec. 
393.86 of this title.
    Rear-end tank protection device means the structure designed to 
protect a cargo tank and any lading retention piping or devices in case 
of a rear end collision.
    Self-closing stop valve means a stop valve held in the closed 
position by means of self-stored energy, that opens only by application 
of an external force and that closes when the external force is removed.
    Shell means the circumferential portion of a cargo tank defined by 
the basic design radius or radii excluding the bulkheads.
    Stop valve means a valve that stops the flow of lading.
    Sump means a protrusion from the bottom of a cargo tank shell 
designed to facilitate complete loading and unloading of lading.
    Tank means a container, consisting of a shell and heads, that forms 
a pressure tight vessel having openings designed to accept pressure 
tight fittings

[[Page 132]]

or closures, but excludes any appurtenances, reinforcements, fittings, 
or closures.
    Test pressure means the pressure to which a tank is subjected to 
determine structural integrity.
    Toughness of material means the capability of a material to absorb 
energy represented by the area under a stress strain curve (indicating 
the energy absorbed per unit volume of the material) up to the point of 
rupture.
    Vacuum cargo tank means a cargo tank that is loaded by reducing the 
pressure in the cargo tank to below atmospheric pressure.
    Variable specification cargo tank means a cargo tank that is 
constructed in accordance with one specification, but that may be 
altered to meet another specification by changing relief device, 
closures, lading discharge devices, and other lading retention devices.
    Void means the space between tank heads or bulkheads and a 
connecting structure.
    Welded flange means a flange attached to the tank by a weld joining 
the tank shell to the cylindrical outer surface of the flange, or by a 
fillet weld joining the tank shell to a flange shaped to fit the shell 
contour.
    (b) Design certification. (1) Each cargo tank or cargo tank motor 
vehicle design type, including its required accident damage protection 
device, must be certified to conform to the specification requirements 
by a Design Certifying Engineer who is registered in accordance with 
subpart F of part 107 of this title. An accident damage protection 
device is a rear-end protection, overturn protection, or piping 
protection device.
    (2) The Design Certifying Engineer shall furnish to the manufacturer 
a certificate to indicate compliance with the specification 
requirements. The certificate must include the sketches, drawings, and 
calculations used for certification. Each certificate, including 
sketches, drawings, and calculations, shall be signed by the Design 
Certifying Engineer.
    (3) The manufacturer shall retain the design certificate at his 
principal place of business for as long as he manufactures DOT 
specification cargo tanks.
    (c) Exceptions to the ASME Code. Unless otherwise specified, when 
exceptions are provided in this subpart from compliance with certain 
paragraphs of the ASME Code, compliance with those paragraphs is not 
prohibited.

[Amdt. 178-89, 55 FR 37055, Sept. 7, 1990, as amended by Amdt. 178-98, 
58 FR 33306, June 16, 1993; Amdt. 178-118, 61 FR 51339, Oct. 1, 1996; 68 
FR 19277, Apr. 18, 2003; 68 FR 52370, Sept. 3, 2003; 68 FR 75752, Dec. 
31, 2003; 76 FR 43532, July 20, 2011]



Sec. 178.337  Specification MC 331; cargo tank motor vehicle primarily
for transportation of compressed gases as defined in subpart G of 
part 173 of this  subchapter.



Sec. 178.337-1  General requirements.

    (a) ASME Code construction. Tanks must be--
    (1) Seamless or welded construction, or a combination of both;
    (2) Designed, constructed, certified, and stamped in accordance with 
Section VIII of the ASME Code (IBR, see Sec. 171.7 of this subchapter);
    (3) Made of steel or aluminum; however, if aluminum is used, the 
cargo tank must be insulated and the hazardous material to be 
transported must be compatible with the aluminum (see Sec. Sec. 
178.337-1(e)(2), 173.315(a) table, and 178.337-2(a)(1) of this 
subchapter); and
    (4) Covered with a steel jacket if the cargo tank is insulated and 
used to transport a flammable gas (see Sec. 173.315(a) table Note 11 of 
this subchapter).
    (b) Design pressure. The design pressure of a cargo tank authorized 
under this specification shall be not less than the vapor pressure of 
the commodity contained therein at 115 [deg]F. or as prescribed for a 
particular commodity in Sec. 173.315(a) of this subchapter, except that 
in no case shall the design pressure of any cargo tank be less than 100 
p.s.i.g. nor more than 500 p.s.i.g.

    Note 1: The term design pressure as used in this specification, is 
identical to the term MAWP as used in the ASME Code.

    (c) Openings. (1) Excess pressure relief valves shall be located in 
the top of the cargo tank or heads.
    (2) A chlorine cargo tank shall have only one opening. That opening 
shall be in the top of the cargo tank and

[[Page 133]]

shall be fitted with a nozzle that meets the following requirements:
    (i) On a cargo tank manufactured on or before December 31, 1974, the 
nozzle shall be protected by a dome cover plate which conforms to either 
the standard of The Chlorine Institute, Inc., Dwg. 103-3, dated January 
23, 1958, or to the standard specified in paragraph (c) (2) (ii) of this 
section.
    (ii) On a cargo tank manufactured on or after January 1, 1975, the 
nozzle shall be protected by a manway cover which conforms to the 
standard of The Chlorine Institute, Inc., Dwg. 103-4, dated September 1, 
1971.
    (d) Reflective design. Every uninsulated cargo tank permanently 
attached to a cargo tank motor vehicle shall, unless covered with a 
jacket made of aluminum, stainless steel, or other bright nontarnishing 
metal, be painted a white, aluminum or similar reflecting color on the 
upper two-thirds of area of the cargo tank.
    (e) Insulation. (1) Each cargo tank required to be insulated must 
conform with the use and performance requirements contained in 
Sec. Sec. 173.315(a) table and 178.337-1 (a)(3) and (e)(2) of this 
subchapter.
    (2) Each cargo tank intended for chlorine; carbon dioxide, 
refrigerated liquid; or nitrous oxide, refrigerated liquid service must 
have suitable insulation of such thickness that the overall thermal 
conductance is not more than 0.08 Btu per square foot per [deg]F 
differential per hour. The conductance must be determined at 60 [deg]F. 
Insulation material used on cargo tanks for nitrous oxide, refrigerated 
liquid must be noncombustible. Insulating material used on cargo tanks 
for chlorine must be corkboard or polyurethane foam, with a minimum 
thickness of 4 inches, or 2 inches minimum thickness of ceramic fiber/
fiberglass of 4 pounds per cubic foot minimum density covered by 2 
inches minimum thickness of fiber.
    (f) Postweld heat treatment. Postweld heat treatment must be as 
prescribed in the ASME Code except that each cargo tank constructed in 
accordance with Part UHT of Section VIII of the ASME Code must be 
postweld heat treated. Each chlorine cargo tank must be fully 
radiographed and postweld heat treated in accordance with the provisions 
in Section VIII of the ASME Code under which it is constructed. Where 
postweld heat treatment is required, the cargo tank must be treated as a 
unit after completion of all the welds in and/or to the shells and 
heads. The method must be as prescribed in Section VIII of the ASME 
Code. Welded attachments to pads may be made after postweld heat 
treatment. A cargo tank used for anhydrous ammonia must be postweld heat 
treated. The postweld heat treatment must be as prescribed in Section 
VIII of the ASME Code, but in no event at less than 1,050 Sec. F cargo 
tank metal temperature.
    (g) Definitions. The following definitions apply to Sec. Sec. 
178.337-1 through 178.337-18:
    Emergency discharge control means the ability to stop a cargo tank 
unloading operation in the event of an unintentional release. Emergency 
discharge control can utilize passive or off-truck remote means to stop 
the unloading operation. A passive means of emergency discharge control 
automatically shuts off the flow of product without the need for human 
intervention within 20 seconds of an unintentional release caused by a 
complete separation of the liquid delivery hose. An off-truck remote 
means of emergency discharge control permits a qualified person 
attending the unloading operation to close the cargo tank's internal 
self-closing stop valve and shut off all motive and auxiliary power 
equipment at a distance from the cargo tank motor vehicle.
    Excess flow valve, integral excess flow valve, or excess flow 
feature means a component that will close automatically if the flow rate 
of a gas or liquid through the component reaches or exceeds the rated 
flow of gas or liquid specified by the original valve manufacturer when 
piping mounted directly on the valve is sheared off before the first 
valve, pump, or fitting downstream from the valve.
    Internal self-closing stop valve means a primary shut off valve 
installed in a product discharge outlet of a cargo tank and designed to 
be kept closed by self-stored energy.
    Primary discharge control system means a primary shut-off installed 
at a product discharge outlet of a cargo

[[Page 134]]

tank consisting of an internal self-closing stop valve that may include 
an integral excess flow valve or an excess flow feature, together with 
linkages that must be installed between the valve and remote actuator to 
provide manual and thermal on-truck remote means of closure.

[Order 59-B, 30 FR 579, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]

    Editorial Note: For Federal Register citations affecting Sec. 
178.337-1, see the List of CFR Sections Affected, which appears in the 
Finding Aids section of the printed volume and at www.fdsys.gov.



Sec. 178.337-2  Material.

    (a) General. (1) All material used for construction of the cargo 
tank and appurtenances must be suitable for use with the commodities to 
be transported therein and must conform to the requirements in Section 
II of the ASME Code (IBR, see Sec. 171.7 of this subchapter) and/or 
requirements of the American Society for Testing and Materials in all 
respects.
    (2) Impact tests are required on steel used in the fabrication of 
each cargo tank constructed in accordance with part UHT in Section VIII 
of the ASME Code. The tests must be made on a lot basis. A lot is 
defined as 100 tons or less of the same heat treatment processing lot 
having a thickness variation no greater than plus or minus 25 percent. 
The minimum impact required for full size specimens must be 20 foot-
pounds in the longitudinal direction at -30 [deg]F., Charpy V-Notch and 
15 foot-pounds in the transverse direction at -30 [deg]F., Charpy V-
Notch. The required values for subsize specimens must be reduced in 
direct proportion to the cross-sectional area of the specimen beneath 
the notch. If a lot does not meet this requirement, individual plates 
may be accepted if they individually meet this requirement.
    (3) The fabricator shall record the heat, and slab numbers, and the 
certified Charpy impact values, where required, of each plate used in 
each cargo tank on a sketch showing the location of each plate in the 
shell and heads of the cargo tank. Copies of each sketch shall be 
provided to the owner and retained for at least five years by the 
fabricator and made available to duly identified representatives of the 
Department of Transportation.
    (4) The direction of final rolling of the shell material shall be 
the circumferential orientation of the cargo tank shell.
    (b) For a chlorine cargo tank. Plates, the manway nozzle, and 
anchorage shall be made of carbon steel which meets the following 
requirements:
    (1) For a cargo tank manufactured on or before December 31, 1974--
    (i) Material shall conform to ASTM A 300, ``Steel Plates for 
Pressure Vessels for Service at Low Temperatures'' (IBR, see Sec. 171.7 
of this subchapter);
    (ii) Material shall be Class 1, Grade A, flange or firebox quality;
    (iii) Plate impact test specimens, as required under paragraph (a) 
of this section, shall be of the Charpy keyhole notch type; and
    (iv) Plate impact test specimens shall meet the impact test 
requirements in paragraph (a) of this section in both the longitudinal 
and transverse directions of rolling at a temperature of minus 45.5 C. 
(-50 [deg]F.).
    (2) For a cargo tank manufactured on or after January 1, 1975--
    (i) Material shall conform to ASTM A 612 (IBR, see Sec. 171.7 of 
this subchapter), Grade B or A 516/A 516M (IBR, see Sec. 171.7 of this 
subchapter), Grade 65 or 70;
    (ii) Material shall meet the Charpy V-notch test requirements of 
ASTM A 20/A 20M (IBR, see Sec. 171.7 of this subchapter); and
    (iii) Plate impact test specimens shall meet the impact test 
requirements in paragraph (a) of this section in both the longitudinal 
and transverse directions of rolling at a temperature of minus 40 
[deg]C. (-40 [deg]F.).
    (c) A cargo tank in anhydrous ammonia service must be constructed of 
steel. The use of copper, silver, zinc or their alloys is prohibited. 
Baffles made from aluminum may be used only if joined to the cargo tank 
by a process not requiring postweld heat treatment of the cargo tank.

[Order 59-B, 30 FR 579, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]

    Editorial Note: For Federal Register citations affecting Sec. 
178.337-2, see the List of CFR Sections Affected, which appears in the 
Finding Aids section of the printed volume and at www.fdsys.gov.

[[Page 135]]



Sec. 178.337-3  Structural integrity.

    (a) General requirements and acceptance criteria. (1) Except as 
provided in paragraph (d) of this section, the maximum calculated design 
stress at any point in the cargo tank may not exceed the maximum 
allowable stress value prescribed in Section VIII of the ASME Code (IBR, 
see Sec. 171.7 of this subchapter), or 25 percent of the tensile 
strength of the material used.
    (2) The relevant physical properties of the materials used in each 
cargo tank may be established either by a certified test report from the 
material manufacturer or by testing in conformance with a recognized 
national standard. In either case, the ultimate tensile strength of the 
material used in the design may not exceed 120 percent of the ultimate 
tensile strength specified in either the ASME Code or the ASTM standard 
to which the material is manufactured.
    (3) The maximum design stress at any point in the cargo tank must be 
calculated separately for the loading conditions described in paragraphs 
(b), (c), and (d) of this section. Alternate test or analytical methods, 
or a combination thereof, may be used in place of the procedures 
described in paragraphs (b), (c), and (d) of this section, if the 
methods are accurate and verifiable.
    (4) Corrosion allowance material may not be included to satisfy any 
of the design calculation requirements of this section.
    (b) Static design and construction. (1) The static design and 
construction of each cargo tank must be in accordance with Section VIII 
of the ASME Code. The cargo tank design must include calculation of 
stresses generated by design pressure, the weight of lading, the weight 
of structure supported by the cargo tank wall, and the effect of 
temperature gradients resulting from lading and ambient temperature 
extremes. When dissimilar materials are used, their thermal coefficients 
must be used in calculation of thermal stresses.
    (2) Stress concentrations in tension, bending and torsion which 
occur at pads, cradles, or other supports must be considered in 
accordance with appendix G in Section VIII of the ASME Code.
    (c) Shell design. Shell stresses resulting from static or dynamic 
loadings, or combinations thereof, are not uniform throughout the cargo 
tank motor vehicle. The vertical, longitudinal, and lateral normal 
operating loadings can occur simultaneously and must be combined. The 
vertical, longitudinal and lateral extreme dynamic loadings occur 
separately and need not be combined.
    (1) Normal operating loadings. The following procedure addresses 
stress in the tank shell resulting from normal operating loadings. The 
effective stress (the maximum principal stress at any point) must be 
determined by the following formula:

S = 0.5(Sy + Sx) [0.25(Sy - Sx)\2\ + 
Ss2]\0.5\


Where:

    (i) S = effective stress at any given point under the combination of 
static and normal operating loadings that can occur at the same time, in 
psi.
    (ii) Sy = circumferential stress generated by the MAWP 
and external pressure, when applicable, plus static head, in psi.
    (iii) Sx = The following net longitudinal stress 
generated by the following static and normal operating loading 
conditions, in psi:
    (A) The longitudinal stresses resulting from the MAWP and external 
pressure, when applicable, plus static head, in combination with the 
bending stress generated by the static weight of the fully loaded cargo 
tank motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall;
    (B) The tensile or compressive stress resulting from normal 
operating longitudinal acceleration or deceleration. In each case, the 
forces applied must be 0.35 times the vertical reaction at the 
suspension assembly, applied at the road surface, and as transmitted to 
the cargo tank wall through the suspension assembly of a trailer during 
deceleration; or the horizontal pivot of the truck tractor or converter 
dolly fifth wheel, or the drawbar hinge on the fixed dolly during 
acceleration; or anchoring and support members of a truck during 
acceleration and deceleration, as applicable. The vertical reaction must 
be calculated based on the

[[Page 136]]

static weight of the fully loaded cargo tank motor vehicle, all 
structural elements, equipment and appurtenances supported by the cargo 
tank wall. The following loadings must be included:
    (1) The axial load generated by a decelerative force;
    (2) The bending moment generated by a decelerative force;
    (3) The axial load generated by an accelerative force; and
    (4) The bending moment generated by an accelerative force; and
    (C) The tensile or compressive stress generated by the bending 
moment resulting from normal operating vertical accelerative force equal 
to 0.35 times the vertical reaction at the suspension assembly of a 
trailer; or the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or anchoring and support members of a truck, as applicable. 
The vertical reaction must be calculated based on the static weight of 
the fully loaded cargo tank motor vehicle, all structural elements, 
equipment and appurtenances supported by the cargo tank wall.
    (iv) Ss = The following shear stresses generated by the 
following static and normal operating loading conditions, in psi:
    (A) The static shear stress resulting from the vertical reaction at 
the suspension assembly of a trailer, and the horizontal pivot of the 
upper coupler (fifth wheel) or turntable; or anchoring and support 
members of a truck, as applicable. The vertical reaction must be 
calculated based on the static weight of the fully loaded cargo tank 
motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall;
    (B) The vertical shear stress generated by a normal operating 
accelerative force equal to 0.35 times the vertical reaction at the 
suspension assembly of a trailer; or the horizontal pivot of the upper 
coupler (fifth wheel) or turntable; or anchoring and support members of 
a truck, as applicable. The vertical reaction must be calculated based 
on the static weight of the fully loaded cargo tank motor vehicle, all 
structural elements, equipment and appurtenances supported by the cargo 
tank wall;
    (C) The lateral shear stress generated by a normal operating lateral 
accelerative force equal to 0.2 times the vertical reaction at each 
suspension assembly of a trailer, applied at the road surface, and as 
transmitted to the cargo tank wall through the suspension assembly of a 
trailer, and the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or anchoring and support members of a truck, as applicable. 
The vertical reaction must be calculated based on the static weight of 
the fully loaded cargo tank motor vehicle, all structural elements, 
equipment and appurtenances supported by the cargo tank wall; and
    (D) The torsional shear stress generated by the same lateral forces 
as described in paragraph (c)(1)(iv)(C) of this section.
    (2) Extreme dynamic loadings. The following procedure addresses 
stress in the tank shell resulting from extreme dynamic loadings. The 
effective stress (the maximum principal stress at any point) must be 
determined by the following formula:

S = 0.5(Sy + Sx) [0.25(Sy - Sx)\2\ + 
Ss2]\0.5\


Where:

    (i) S = effective stress at any given point under a combination of 
static and extreme dynamic loadings that can occur at the same time, in 
psi.
    (ii) Sy = circumferential stress generated by MAWP and 
external pressure, when applicable, plus static head, in psi.
    (iii) Sx = the following net longitudinal stress 
generated by the following static and extreme dynamic loading 
conditions, in psi:
    (A) The longitudinal stresses resulting from the MAWP and external 
pressure, when applicable, plus static head, in combination with the 
bending stress generated by the static weight of the fully loaded cargo 
tank motor vehicle, all structural elements, equipment and appurtenances 
supported by the tank wall;
    (B) The tensile or compressive stress resulting from extreme 
longitudinal acceleration or deceleration. In each case the forces 
applied must be 0.7 times the vertical reaction at the suspension 
assembly, applied at the road surface, and as transmitted to the

[[Page 137]]

cargo tank wall through the suspension assembly of a trailer during 
deceleration; or the horizontal pivot of the truck tractor or converter 
dolly fifth wheel, or the drawbar hinge on the fixed dolly during 
acceleration; or the anchoring and support members of a truck during 
acceleration and deceleration, as applicable. The vertical reaction must 
be calculated based on the static weight of the fully loaded cargo tank 
motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall. The following loadings must be 
included:
    (1) The axial load generated by a decelerative force;
    (2) The bending moment generated by a decelerative force;
    (3) The axial load generated by an accelerative force; and
    (4) The bending moment generated by an accelerative force; and
    (C) The tensile or compressive stress generated by the bending 
moment resulting from an extreme vertical accelerative force equal to 
0.7 times the vertical reaction at the suspension assembly of a trailer, 
and the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or the anchoring and support members of a truck, as 
applicable. The vertical reaction must be calculated based on the static 
weight of the fully loaded cargo tank motor vehicle, all structural 
elements, equipment and appurtenances supported by the cargo tank wall.
    (iv) Ss = The following shear stresses generated by 
static and extreme dynamic loading conditions, in psi:
    (A) The static shear stress resulting from the vertical reaction at 
the suspension assembly of a trailer, and the horizontal pivot of the 
upper coupler (fifth wheel) or turntable; or anchoring and support 
members of a truck, as applicable. The vertical reaction must be 
calculated based on the static weight of the fully loaded cargo tank 
motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall;
    (B) The vertical shear stress generated by an extreme vertical 
accelerative force equal to 0.7 times the vertical reaction at the 
suspension assembly of a trailer, and the horizontal pivot of the upper 
coupler (fifth wheel) or turntable; or anchoring and support members of 
a truck, as applicable. The vertical reaction must be calculated based 
on the static weight of the fully loaded cargo tank motor vehicle, all 
structural elements, equipment and appurtenances supported by the cargo 
tank wall;
    (C) The lateral shear stress generated by an extreme lateral 
accelerative force equal to 0.4 times the vertical reaction at the 
suspension assembly of a trailer, applied at the road surface, and as 
transmitted to the cargo tank wall through the suspension assembly of a 
trailer, and the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or anchoring and support members of a truck, as applicable. 
The vertical reaction must be calculated based on the static weight of 
the fully loaded cargo tank motor vehicle, all structural elements, 
equipment and appurtenances supported by the cargo tank wall; and
    (D) The torsional shear stress generated by the same lateral forces 
as described in paragraph (c)(2)(iv)(C) of this section.
    (d) In order to account for stresses due to impact in an accident, 
the design calculations for the cargo tank shell and heads must include 
the load resulting from the design pressure in combination with the 
dynamic pressure resulting from a longitudinal deceleration of ``2g''. 
For this loading condition the stress value used may not exceed the 
lesser of the yield strength or 75 percent of the ultimate tensile 
strength of the material of construction. For cargo tanks constructed of 
stainless steel the maximum design stress may not exceed 75 percent of 
the ultimate tensile strength of the type steel used.
    (e) The minimum metal thickness for the shell and heads on tanks 
with a design pressure of 100 psig or more must be 4.75 mm (0.187 inch) 
for steel and 6.86 mm (0.270 inch) for aluminum, except for chlorine and 
sulfur dioxide tanks. In all cases, the minimum thickness of the tank 
shell and head shall be determined using structural design requirements 
in Section VIII of the ASME Code or 25% of the tensile strength of the 
material used. For a cargo tank

[[Page 138]]

used in chlorine or sulfur dioxide service, the cargo tank must be made 
of steel. A corrosion allowance of 20 percent or 2.54 mm (0.10 inch), 
whichever is less, must be added to the thickness otherwise required for 
sulfur dioxide and chlorine tank material. In chlorine cargo tanks, the 
wall thickness must be at least 1.59 cm (0.625 inch), including 
corrosion allowance.
    (f) Where a cargo tank support is attached to any part of the cargo 
tank wall, the stresses imposed on the cargo tank wall must meet the 
requirements in paragraph (a) of this section.
    (g) The design, construction, and installation of an attachment, 
appurtenance to the cargo tank, structural support member between the 
cargo tank and the vehicle or suspension component, or accident 
protection device must conform to the following requirements:
    (1) Structural members, the suspension sub-frame, accident 
protection structures, and external circumferential reinforcement 
devices must be used as sites for attachment of appurtenances and other 
accessories to the cargo tank, when practicable.
    (2) A lightweight attachment to the cargo tank wall such as a 
conduit clip, brake line clip, skirting structure, lamp mounting 
bracket, or placard holder must be of a construction having lesser 
strength than the cargo tank wall materials and may not be more than 72 
percent of the thickness of the material to which it is attached. The 
lightweight attachment may be secured directly to the cargo tank wall if 
the device is designed and installed in such a manner that, if damaged, 
it will not affect the lading retention integrity of the tank. A 
lightweight attachment must be secured to the cargo tank shell or head 
by a continuous weld or in such a manner as to preclude formation of 
pockets which may become sites for corrosion. Attachments meeting the 
requirements of this paragraph are not authorized for cargo tanks 
constructed under part UHT in Section VIII of the ASME Code.
    (3) Except as prescribed in paragraphs (g)(1) and (g)(2) of this 
section, the welding of any appurtenance to the cargo tank wall must be 
made by attachment of a mounting pad so that there will be no adverse 
effect upon the lading retention integrity of the cargo tank if any 
force less than that prescribed in paragraph (b)(1) of this section is 
applied from any direction. The thickness of the mounting pad may not be 
less than that of the shell wall or head wall to which it is attached, 
and not more than 1.5 times the shell or head thickness. However, a pad 
with a minimum thickness of 0.25 inch may be used when the shell or head 
thickness is over 0.25 inch. If weep holes or tell-tale holes are used, 
the pad must be drilled or punched at the lowest point before it is 
welded to the tank. Each pad must--
    (i) Be fabricated from material determined to be suitable for 
welding to both the cargo tank material and the material of the 
appurtenance or structural support member; a Design Certifying Engineer 
must make this determination considering chemical and physical 
properties of the materials and must specify filler material conforming 
to the requirements in Section VIII of the ASME Code (IBR, see Sec. 
171.7 of this subchapter).
    (ii) Be preformed to an inside radius no greater than the outside 
radius of the cargo tank at the attachment location.
    (iii) Extend at least 2 inches in each direction from any point of 
attachment of an appurtenance or structural support member. This 
dimension may be measured from the center of the attached structural 
member.
    (iv) Have rounded corners, or otherwise be shaped in a manner to 
minimize stress concentrations on the shell or head.
    (v) Be attached by continuous fillet welding. Any fillet weld 
discontinuity may only be for the purpose of preventing an intersection 
between the fillet weld and a tank or jacket seam weld.

[Amdt. 178-89, 55 FR 37056, Sept. 7, 1990, as amended by Amdt. 178-104, 
59 FR 49135, Sept. 26, 1994; Amdt. 178-105, 60 FR 17401, Apr. 5, 1995; 
Amdt. 178-118, 61 FR 51340, Oct. 1, 1996; 65 FR 58631, Sept. 29, 2000; 
68 FR 19279, Apr. 18, 2003; 68 FR 52370, Sept. 3, 2003; 68 FR 75753, 
Dec. 31, 2003]

[[Page 139]]



Sec. 178.337-4  Joints.

    (a) Joints shall be as required in Section VIII of the ASME Code 
(IBR, see Sec. 171.7 of this subchapter), with all undercutting in 
shell and head material repaired as specified therein.
    (b) Welding procedure and welder performance must be in accordance 
with Section IX of the ASME Code. In addition to the essential variables 
named therein, the following must be considered as essential variables: 
Number of passes; thickness of plate; heat input per pass; and 
manufacturer's identification of rod and flux. When fabrication is done 
in accordance with part UHT in Section VIII of the ASME Code, filler 
material containing more than 0.08 percent vanadium must not be used. 
The number of passes, thickness of plate, and heat input per pass may 
not vary more than 25 percent from the procedure or welder 
qualifications. Records of the qualifications must be retained for at 
least 5 years by the cargo tank manufacturer and must be made available 
to duly identified representatives of the Department and the owner of 
the cargo tank.
    (c) All longitudinal shell welds shall be located in the upper half 
of the cargo tank.
    (d) Edge preparation of shell and head components may be by machine 
heat processes, provided such surfaces are remelted in the subsequent 
welding process. Where there will be no subsequent remelting of the 
prepared surface as in a tapered section, the final 0.050 inch of 
material shall be removed by mechanical means.
    (e) The maximum tolerance for misalignment and butting up shall be 
in accordance with the requirement in Section VIII of the ASME Code.
    (f) Substructures shall be properly fitted before attachment, and 
the welding sequence shall be such as to minimize stresses due to 
shrinkage of welds.

[Order 59-B, 30 FR 580, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]

    Editorial Note: For Federal Register citations affecting Sec. 
178.337-4, see the List of CFR Sections Affected, which appears in the 
Finding Aids section of the printed volume and at www.fdsys.gov.



Sec. 178.337-5  Bulkheads, baffles and ring stiffeners.

    (a) Not a specification requirement.
    (b) [Reserved]

[Order 59-B, 30 FR 580, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]



Sec. 178.337-6  Closure for manhole.

    (a) Each cargo tank marked or certified after April 21, 1994, must 
be provided with a manhole conforming to paragraph UG-46(g)(1) and other 
applicable requirements in Section VIII of the ASME Code (IBR, see Sec. 
171.7 of this subchapter), except that a cargo tank constructed of NQT 
steel having a capacity of 3,500 water gallons or less may be provided 
with an inspection opening conforming to paragraph UG-46 and other 
applicable requirements of the ASME Code instead of a manhole.
    (b) The manhole assembly of cargo tanks constructed after June 30, 
1979, may not be located on the front head of the cargo tank.

[Amdt. 178-7, 34 FR 18250, Nov. 14, 1969, as amended by Amdt. 178-52, 43 
FR 58820, Dec. 18, 1978; Amdt. 178-89, 54 FR 25017, June 12, 1989; 55 FR 
21038, May 22, 1990; 56 FR 27876, June 17, 1991; 58 FR 12905, Mar. 8, 
1993; Amdt. 178-118, 61 FR 51340, Oct. 1, 1996; 68 FR 75753, Dec. 31, 
2003]



Sec. 178.337-7  Overturn protection.

    (a) See Sec. 178.337-10.
    (b) [Reserved]

[Order 59-B, 30 FR 580, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]



Sec. 178.337-8  Openings, inlets, and outlets.

    (a) General. The requirements in this paragraph (a) apply to MC 331 
cargo tanks except for those used to transport chlorine. The 
requirements for inlets and outlets on chlorine cargo tanks are in 
paragraph (b) of this section.
    (1) An opening must be provided on each cargo tank used for the 
transportation of liquefied materials to permit complete drainage.
    (2) Except for gauging devices, thermometer wells, pressure relief 
valves, manhole openings, product inlet openings, and product discharge 
openings, each opening in a cargo tank must be

[[Page 140]]

closed with a plug, cap, or bolted flange.
    (3) Except as provided in paragraph (b) of this section, each 
product inlet opening, including vapor return lines, must be fitted with 
a back flow check valve or an internal self-closing stop valve located 
inside the cargo tank or inside a welded nozzle that is an integral part 
of the cargo tank. The valve seat must be located inside the cargo tank 
or within 2.54 cm (one inch) of the external face of the welded flange. 
Damage to parts exterior to the cargo tank or mating flange must not 
prevent effective seating of the valve. All parts of a valve inside a 
cargo tank or welded flange must be made of material that will not 
corrode or deteriorate in the presence of the lading.
    (4) Except as provided in paragraphs (a)(5), (b), and (c) of this 
section, each liquid or vapor discharge outlet must be fitted with a 
primary discharge control system as defined in Sec. 178.337-1(g). 
Thermal remote operators must activate at a temperature of 121.11 [deg]C 
(250 [deg]F) or less. Linkages between closures and remote operators 
must be corrosion resistant and effective in all types of environmental 
conditions incident to discharging of product.
    (i) On a cargo tank over 13,247.5 L (3,500 gallons) water capacity, 
thermal and mechanical means of remote closure must be installed at the 
ends of the cargo tank in at least two diagonally opposite locations. If 
the loading/unloading connection at the cargo tank is not in the general 
vicinity of one of the two locations specified in the first sentence of 
this paragraph (a)(4)(i), additional means of thermal remote closure 
must be installed so that heat from a fire in the loading/unloading 
connection area or the discharge pump will activate the primary 
discharge control system. The loading/unloading connection area is where 
hoses or hose reels are connected to the permanent metal piping.
    (ii) On a cargo tank of 13,247.5 L (3,500 gallons) water capacity or 
less, a thermal means of remote closure must be installed at or near the 
internal self-closing stop valve. A mechanical means of remote closure 
must be installed on the end of the cargo tank furthest away from the 
loading/unloading connection area. The loading/unloading connection area 
is where hoses or hose reels are connected to the permanent metal 
piping. Linkages between closures and remote operators must be corrosion 
resistant and effective in all types of environmental conditions 
incident to discharge of product.
    (iii) All parts of a valve inside a cargo tank or within a welded 
flange must be made of material that will not corrode or deteriorate in 
the presence of the lading.
    (iv) An excess flow valve, integral excess flow valve, or excess 
flow feature must close if the flow reaches the rated flow of a gas or 
liquid specified by the original valve manufacturer when piping mounted 
directly on the valve is sheared off before the first valve, pump, or 
fitting downstream from the excess flow valve, integral excess flow 
valve, or excess flow feature.
    (v) An integral excess flow valve or the excess flow feature of an 
internal self-closing stop valve may be designed with a bypass, not to 
exceed 0.1016 cm (0.040 inch) diameter opening, to allow equalization of 
pressure.
    (vi) The internal self-closing stop valve must be designed so that 
the self-stored energy source and the valve seat are located inside the 
cargo tank or within 2.54 cm (one inch) of the external face of the 
welded flange. Damage to parts exterior to the cargo tank or mating 
flange must not prevent effective seating of the valve.
    (5) A primary discharge control system is not required on the 
following:
    (i) A vapor or liquid discharge opening of less than 1\1/4\ NPT 
equipped with an excess flow valve together with a manually operated 
external stop valve in place of an internal self-closing stop valve.
    (ii) An engine fuel line on a truck-mounted cargo tank of not more 
than \3/4\ NPT equipped with a valve having an integral excess flow 
valve or excess flow feature.
    (iii) A cargo tank motor vehicle used to transport refrigerated 
liquids such as argon, carbon dioxide, helium, krypton, neon, nitrogen, 
and xenon, or mixtures thereof.

[[Page 141]]

    (6) In addition to the internal self-closing stop valve, each 
filling and discharge line must be fitted with a stop valve located in 
the line between the internal self-closing stop valve and the hose 
connection. A back flow check valve or excess flow valve may not be used 
to satisfy this requirement.
    (7) An excess flow valve may be designed with a bypass, not to 
exceed a 0.1016 centimeter (0.040 inch) diameter opening, to allow 
equalization of pressure.
    (b) Inlets and discharge outlets on chlorine tanks. The inlet and 
discharge outlets on a cargo tank used to transport chlorine must meet 
the requirements of Sec. 178.337-1(c)(2) and must be fitted with an 
internal excess flow valve. In addition to the internal excess flow 
valve, the inlet and discharge outlets must be equipped with an external 
stop valve (angle valve). Excess flow valves must conform to the 
standards of The Chlorine Institute, Inc., as follows:
    (1) A valve conforming to The Chlorine Institute, Inc., Dwg. 101-7 
(IBR, see Sec. 171.7 of this subchapter), must be installed under each 
liquid angle valve.
    (2) A valve conforming to The Chlorine Institute, Inc., Dwg. 106-6 
(IBR, see Sec. 171.7 of this subchapter), must be installed under each 
gas angle valve.
    (c) Discharge outlets on carbon dioxide, refrigerated liquid, cargo 
tanks. A discharge outlet on a cargo tank used to transport carbon 
dioxide, refrigerated liquid is not required to be fitted with an 
internal self-closing stop valve.

[64 FR 28049, May 24, 1999, as amended at 66 FR 45387, Aug. 28, 2001; 68 
FR 19279, Apr. 18, 2003; 68 FR 75753, Dec. 31, 2003]



Sec. 178.337-9  Pressure relief devices, piping, valves, hoses, and fittings.

    (a) Pressure relief devices. (1) See Sec. 173.315(i) of this 
subchapter.
    (2) On cargo tanks for carbon dioxide or nitrous oxide see Sec. 
173.315 (i) (9) and (10) of this subchapter.
    (3) Each valve must be designed, constructed, and marked for a rated 
pressure not less than the cargo tank design pressure at the temperature 
expected to be encountered.
    (b) Piping, valves, hose, and fittings. (1) The burst pressure of 
all piping, pipe fittings, hose and other pressure parts, except for 
pump seals and pressure relief devices, must be at least 4 times the 
design pressure of the cargo tank. Additionally, the burst pressure may 
not be less than 4 times any higher pressure to which each pipe, pipe 
fitting, hose or other pressure part may be subjected to in service. For 
chlorine service, see paragraph (b)(7) of this section.
    (2) Pipe joints must be threaded, welded, or flanged. If threaded 
pipe is used, the pipe and fittings must be Schedule 80 weight or 
heavier, except for sacrificial devices. Malleable metal, stainless 
steel, or ductile iron must be used in the construction of primary valve 
body parts and fittings used in liquid filling or vapor equalization. 
Stainless steel may be used for internal components such as shutoff 
discs and springs except where incompatible with the lading to be 
transported. Where copper tubing is permitted, joints must be brazed or 
be of equally strong metal union type. The melting point of the brazing 
material may not be lower than 538 [deg]C (1,000 [deg]F). The method of 
joining tubing may not reduce the strength of the tubing.
    (3) Each hose coupling must be designed for a pressure of at least 
120 percent of the hose design pressure and so that there will be no 
leakage when connected.
    (4) Piping must be protected from damage due to thermal expansion 
and contraction, jarring, and vibration. Slip joints are not authorized 
for this purpose.
    (5) [Reserved]
    (6) Cargo tank manufacturers and fabricators must demonstrate that 
all piping, valves, and fittings on a cargo tank are free from leaks. To 
meet this requirement, the piping, valves, and fittings must be tested 
after installation at not less than 80 percent of the design pressure 
marked on the cargo tank.
    (7) A hose assembler must:
    (i) Permanently mark each hose assembly with a unique identification 
number.
    (ii) Demonstrate that each hose assembly is free from leaks by 
performing the tests and inspections in Sec. 180.416(f) of this 
subchapter.

[[Page 142]]

    (iii) Mark each hose assembly with the month and year of its 
original pressure test.
    (8) Chlorine cargo tanks. Angle valves on cargo tanks intended for 
chlorine service must conform to the standards of the Chlorine 
Institute, Inc., Dwg. 104-8 or ``Section 3, Pamphlet 166, Angle Valve 
Guidelines for Chlorine Bulk Transportation.'' (IBR, see Sec. 171.7 of 
this subchapter). Before installation, each angle valve must be tested 
for leakage at not less than 225 psig using dry air or inert gas.
    (c) Marking inlets and outlets. Except for gauging devices, 
thermometer wells, and pressure relief valves, each cargo tank inlet and 
outlet must be marked ``liquid'' or ``vapor'' to designate whether it 
communicates with liquid or vapor when the cargo tank is filled to the 
maximum permitted filling density. A filling line that communicates with 
vapor may be marked ``spray-fill'' instead of ``vapor.''
    (d) Refrigeration and heating coils. (1) Refrigeration and heating 
coils must be securely anchored with provisions for thermal expansion. 
The coils must be pressure tested externally to at least the cargo tank 
test pressure, and internally to either the tank test pressure or twice 
the working pressure of the heating/refrigeration system, whichever is 
higher. A cargo tank may not be placed in service if any leakage occurs 
or other evidence of damage is found. The refrigerant or heating medium 
to be circulated through the coils must not be capable of causing any 
adverse chemical reaction with the cargo tank lading in the event of 
leakage. The unit furnishing refrigeration may be mounted on the motor 
vehicle.
    (2) Where any liquid susceptible to freezing, or the vapor of any 
such liquid, is used for heating or refrigeration, the heating or 
refrigeration system shall be arranged to permit complete drainage.

[Order 59-B, 30 FR 580, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]

    Editorial Note: For Federal Register citations affecting Sec. 
178.337-9, see the List of CFR Sections Affected, which appears in the 
Finding Aids section of the printed volume and at www.fdsys.gov.



Sec. 178.337-10  Accident damage protection.

    (a) All valves, fittings, pressure relief devices, and other 
accessories to the tank proper shall be protected in accordance with 
paragraph (b) of this section against such damage as could be caused by 
collision with other vehicles or objects, jack-knifing and overturning. 
In addition, pressure relief valves shall be so protected that in the 
event of overturn of the vehicle onto a hard surface, their opening will 
not be prevented and their discharge will not be restricted.
    (b) The protective devices or housing must be designed to withstand 
static loading in any direction equal to twice the weight of the tank 
and attachments when filled with the lading, using a safety factor of 
not less than four, based on the ultimate strength of the material to be 
used, without damage to the fittings protected, and must be made of 
metal at least \3/16\-inch thick.
    (c) Rear-end tank protection. Rear-end tank protection devices must:
    (1) Consist of at least one rear bumper designed to protect the 
cargo tank and all valves, piping and fittings located at the rear of 
the cargo tank from damage that could result in loss of lading in the 
event of a rear end collision. The bumper design must transmit the force 
of the collision directly to the chassis of the vehicle. The rear bumper 
and its attachments to the chassis must be designed to withstand a load 
equal to twice the weight of the loaded cargo tank motor vehicle and 
attachments, using a safety factor of four based on the tensile strength 
of the materials used, with such load being applied horizontally and 
parallel to the major axis of the cargo tank. The rear bumper dimensions 
must also meet the requirements of Sec. 393.86 of this title; or
    (2) Conform to the requirements of Sec. 178.345-8(d).
    (d) Chlorine tanks. A chlorine tank must be equipped with a 
protective housing and a manway cover to permit the use of standard 
emergency kits for controlling leaks in fittings on the dome cover 
plate. For tanks manufactured on or after October 1, 2009, the

[[Page 143]]

housing and manway cover must conform to the Chlorine Institute, Inc., 
Dwg. 137-5 (IBR, see Sec. 171.7 of this subchapter).
    (e) Piping and fittings. Piping and fittings must be grouped in the 
smallest practicable space and protected from damage as required in this 
section.
    (f) Shear section. A shear section or sacrificial device is required 
for the valves specified in the following locations:
    (1) A section that will break under strain must be provided adjacent 
to or outboard of each valve specified in Sec. 178.337-8(a)(3) and (4).
    (2) Each internal self-closing stop valve, excess flow valve, and 
check valve must be protected by a shear section or other sacrificial 
device. The sacrificial device must be located in the piping system 
outboard of the stop valve and within the accident damage protection to 
prevent any accidental loss of lading. The failure of the sacrificial 
device must leave the protected lading protection device and its 
attachment to the cargo tank wall intact and capable of retaining 
product.

[Order 59-B, 30 FR 581, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]

    Editorial Note: For Federal Register citations affecting Sec. 
178.337-10, see the List of CFR Sections Affected, which appears in the 
Finding Aids section of the printed volume and at www.fdsys.gov.



Sec. 178.337-11  Emergency discharge control.

    (a) Emergency discharge control equipment. Emergency discharge 
control equipment must be installed in a liquid discharge line as 
specified by product and service in Sec. 173.315(n) of this subchapter. 
The performance and certification requirements for emergency discharge 
control equipment are specified in Sec. 173.315(n) of this subchapter 
and are not a part of the cargo tank motor vehicle certification made 
under this specification.
    (b) Engine fuel lines. On a truck-mounted cargo tank, emergency 
discharge control equipment is not required on an engine fuel line of 
not more than \3/4\ NPT equipped with a valve having an integral excess 
flow valve or excess flow feature.

[64 FR 28050, May 24, 1999]



Sec. 178.337-12  [Reserved]



Sec. 178.337-13  Supporting and anchoring.

    (a) A cargo tank that is not permanently attached to or integral 
with a vehicle chassis must be secured by the use of restraining devices 
designed to prevent relative motion between the cargo tank and the 
vehicle chassis when the vehicle is in operation. Such restraining 
devices must be readily accessible for inspection and maintenance.
    (b) On a cargo tank motor vehicle designed and constructed so that 
the cargo tank constitutes in whole or in part the structural member 
used in place of a motor vehicle frame, the cargo tank must be supported 
by external cradles. A cargo tank mounted on a motor vehicle frame must 
be supported by external cradles or longitudinal members. Where used, 
the cradles must subtend at least 120 degrees of the shell 
circumference.
    (c) The design calculations of the support elements must satisfy the 
requirements of Sec. 178.337-3, (a), (b), (c), and (d).
    (d) Where any cargo tank support is attached to any part of a cargo 
tank head, the stresses imposed upon the head must be provided for as 
required in paragraph (c) of this section.

[68 FR 19280, Apr. 18, 2003]



Sec. 178.337-14  Gauging devices.

    (a) Liquid level gauging devices. See Sec. 173.315(h) of this 
subchapter.
    (b) Pressure gauges. (1) See Sec. 173.315(h) of this subchapter.
    (2) Each cargo tank used in carbon dioxide, refrigerated liquid or 
nitrous oxide, refrigerated liquid service must be provided with a 
suitable pressure gauge. A shut-off valve must be installed between the 
pressure gauge and the cargo tank.
    (c) Orifices. See Sec. 173.315(h) (3) and (4) of this subchapter.

[Amdt. 178-29, 38 FR 27599, Oct. 5, 1973, as amended by Amdt. 178-89, 54 
FR 25018, June 12, 1989; Amdt. 178-118, 61 FR 51340, Oct. 1, 1996]

[[Page 144]]



Sec. 178.337-15  Pumps and compressors.

    (a) Liquid pumps or gas compressors, if used, must be of suitable 
design, adequately protected against breakage by collision, and kept in 
good condition. They may be driven by motor vehicle power take-off or 
other mechanical, electrical, or hydraulic means. Unless they are of the 
centrifugal type, they shall be equipped with suitable pressure actuated 
by-pass valves permitting flow from discharge to suction or to the cargo 
tank.
    (b) A liquid chlorine pump may not be installed on a cargo tank 
intended for the transportation of chlorine.

[Amdt. 178-89, 54 FR 25018, June 12, 1989, as amended by Amdt. 178-118, 
61 FR 51340, Oct. 1, 1996]



Sec. 178.337-16  Testing.

    (a) Inspection and tests. Inspection of materials of construction of 
the cargo tank and its appurtenances and original test and inspection of 
the finished cargo tank and its appurtenances must be as required by 
Section VIII of the ASME Code (IBR, see Sec. 171.7 of this subchapter) 
and as further required by this specification, except that for cargo 
tanks constructed in accordance with part UHT in Section VIII of the 
ASME Code the original test pressure must be at least twice the cargo 
tank design pressure.
    (b) Weld testing and inspection. (1) Each cargo tank constructed in 
accordance with part UHT in Section VIII of the ASME Code must be 
subjected, after postweld heat treatment and hydrostatic tests, to a wet 
fluorescent magnetic particle inspection to be made on all welds in or 
on the cargo tank shell and heads both inside and out. The method of 
inspection must conform to appendix 6 in Section VIII of the ASME Code 
except that permanent magnets shall not be used.
    (2) On cargo tanks of over 3,500 gallons water capacity other than 
those described in paragraph (b)(1) of this section unless fully 
radiographed, a test must be made of all welds in or on the shell and 
heads both inside and outside by either the wet fluorescent magnetic 
particle method conforming to appendix U in Section VIII of the ASME 
Code, liquid dye penetrant method, or ultrasonic testing in accordance 
with appendix 12 in Section VIII of the ASME Code. Permanent magnets 
must not be used to perform the magnetic particle inspection.
    (c) All defects found shall be repaired, the cargo tanks shall then 
again be postweld heat treated, if such heat treatment was previously 
performed, and the repaired areas shall again be tested.

[Order 59-B, 30 FR 582, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967, and amended by Amdt. 178-7, 34 FR 18250, Nov. 14, 1969; Amdt. 
178-99, 58 FR 51534, Oct. 1, 1993; Amdt. 178-118, 61 FR 51340, Oct. 1, 
1996; 68 FR 75753, Dec. 31, 2003]



Sec. 178.337-17  Marking.

    (a) General. Each cargo tank certified after October 1, 2004 must 
have a corrosion-resistant metal name plate (ASME Plate) and 
specification plate permanently attached to the cargo tank by brazing, 
welding, or other suitable means on the left side near the front, in a 
place accessible for inspection. If the specification plate is attached 
directly to the cargo tank wall by welding, it must be welded to the 
tank before the cargo tank is postweld heat treated.
    (1) The plates must be legibly marked by stamping, embossing, or 
other means of forming letters into the metal of the plate, with the 
information required in paragraphs (b) and (c) of this section, in 
addition to that required by the ASME Code, in characters at least \3/
16\ inch high (parenthetical abbreviations may be used). All plates must 
be maintained in a legible condition.
    (2) Each insulated cargo tank must have additional plates, as 
described, attached to the jacket in the location specified unless the 
specification plate is attached to the chassis and has the information 
required in paragraphs (b) and (c) of this section.
    (3) The information required for both the name and specification 
plate may be displayed on a single plate. If the information required by 
this section is displayed on a plate required by the ASME, the 
information need not be repeated on the name and specification plates.

[[Page 145]]

    (4) The specification plate may be attached to the cargo tank motor 
vehicle chassis rail by brazing, welding, or other suitable means on the 
left side near the front head, in a place accessible for inspection. If 
the specification plate is attached to the chassis rail, then the cargo 
tank serial number assigned by the cargo tank manufacturer must be 
included on the plate.
    (b) Name plate. The following information must be marked on the name 
plate in accordance with this section:
    (1) DOT-specification number MC 331 (DOT MC 331).
    (2) Original test date (Orig. Test Date).
    (3) MAWP in psig.
    (4) Cargo tank design temperature (Design Temp. Range) ------ [deg]F 
to ------ [deg]F.
    (5) Nominal capacity (Water Cap.), in pounds.
    (6) Maximum design density of lading (Max. Lading density), in 
pounds per gallon.
    (7) Material specification number--shell (Shell matl, yyy***), where 
``yyy'' is replaced by the alloy designation and ``***'' is replaced by 
the alloy type.
    (8) Material specification number--heads (Head matl. yyy***), where 
``yyy'' is replaced by the alloy designation and ``***'' by the alloy 
type.
    (9) Minimum Thickness--shell (Min. Shell-thick), in inches. When 
minimum shell thicknesses are not the same for different areas, show 
(top----, side----, bottom----, in inches).
    (10) Minimum thickness--heads (Min. heads thick.), in inches.
    (11) Manufactured thickness--shell (Mfd. Shell thick.), top----, 
side----, bottom----, in inches. (Required when additional thickness is 
provided for corrosion allowance.)
    (12) Manufactured thickness--heads (Mfd. Heads thick.), in inches. 
(Required when additional thickness is provided for corrosion 
allowance.)
    (13) Exposed surface area, in square feet.

    Note to paragraph (b): When the shell and head materials are the 
same thickness, they may be combined, (Shell&head matl, yyy***).

    (c) Specification plate. The following information must be marked on 
the specification plate in accordance with this section:
    (1) Cargo tank motor vehicle manufacturer (CTMV mfr.).
    (2) Cargo tank motor vehicle certification date (CTMV cert. date).
    (3) Cargo tank manufacturer (CT mfr.).
    (4) Cargo tank date of manufacture (CT date of mfr.), month and 
year.
    (5) Maximum weight of lading (Max. Payload), in pounds
    (6) Lining materials (Lining), if applicable.
    (7) Heating system design pressure (Heating sys. press.), in psig, 
if applicable.
    (8) Heating system design temperature (Heating sys. temp.), in 
[deg]F, if applicable.
    (9) Cargo tank serial number, assigned by cargo tank manufacturer 
(CT serial), if applicable.

    Note 1 to paragraph (c): See Sec. 173.315(a) of this chapter 
regarding water capacity.
    Note 2 to paragraph (c): When the shell and head materials are the 
same thickness, they may be combined (Shell & head matl, yyy***).

    (d) The design weight of lading used in determining the loading in 
Sec. Sec. 178.337-3(b), 178.337-10(b) and (c), and 178.337-13(a) and 
(b), must be shown as the maximum weight of lading marking required by 
paragraph (c) of this section.

[68 FR 19280, Apr. 18, 2003; 68 FR 52370, Sept. 3, 2003, as amended at 
68 FR 57633, Oct. 6, 2003]



Sec. 178.337-18  Certification.

    (a) At or before the time of delivery, the cargo tank motor vehicle 
manufacturer must supply and the owner must obtain, a cargo tank motor 
vehicle manufacturer's data report as required by Section VIII of the 
ASME Code (IBR, see Sec. 171.7 of this subchapter), and a certificate 
stating that the completed cargo tank motor vehicle conforms in all 
respects to Specification MC 331 and the ASME Code. The registration 
numbers of the manufacturer, the Design Certifying Engineer, and the 
Registered Inspector, as appropriate, must appear on the certificates 
(see subpart F, part 107 in subchapter A of this chapter).

[[Page 146]]

    (1) For each design type, the certificate must be signed by a 
responsible official of the manufacturer and a Design Certifying 
Engineer; and
    (2) For each cargo tank motor vehicle, the certificate must be 
signed by a responsible official of the manufacturer and a Registered 
Inspector.
    (3) When a cargo tank motor vehicle is manufactured in two or more 
stages, each manufacturer who performs a manufacturing function or 
portion thereof on the incomplete cargo tank motor vehicle must provide 
to the succeeding manufacturer, at or before the time of delivery, a 
certificate that states the function performed by the manufacturer, 
including any certificates received from previous manufacturers, 
Registered Inspectors, and Design Certifying Engineers.
    (4) Specification shortages. When a cargo tank motor vehicle is 
manufactured in two or more stages, the manufacturer of the cargo tank 
must attach the name plate and specification plate as required by Sec. 
178.337-17(a) and (b) without the original date of certification stamped 
on the specification plate. Prior manufacturers must list the 
specification requirements that are not completed on the Certificate of 
Compliance. When the cargo tank motor vehicle is brought into full 
compliance with the applicable specification, the cargo tank motor 
vehicle manufacturer must have a Registered Inspector stamp the date of 
certification on the specification plate and issue a Certificate of 
Compliance to the owner of the cargo tank motor vehicle. The Certificate 
of Compliance must list the actions taken to bring the cargo tank motor 
vehicle into full compliance. In addition, the certificate must include 
the date of certification and the person (manufacturer, carrier or 
repair organization) accomplishing compliance.
    (5) The certificate must state whether or not it includes 
certification that all valves, piping, and protective devices conform to 
the requirements of the specification. If it does not so certify, the 
installer of any such valve, piping, or device shall supply and the 
owner shall obtain a certificate asserting complete compliance with 
these specifications for such devices. The certificate, or certificates, 
will include sufficient sketches, drawings, and other information to 
indicate the location, make, model, and size of each valve and the 
arrangement of all piping associated with the cargo tank.
    (6) The certificate must contain a statement indicating whether or 
not the cargo tank was postweld heat treated for anhydrous ammonia as 
specified in Sec. 178.337-1(f).
    (b) The owner shall retain the copy of the data report and 
certificates and related papers in his files throughout his ownership of 
the cargo tank motor vehicle and for at least one year thereafter; and 
in the event of change in ownership, retention by the prior owner of 
nonfading photographically reproduced copies will be deemed to satisfy 
this requirement. Each motor carrier using the cargo tank motor vehicle, 
if not the owner thereof, shall obtain a copy of the data report and 
certificate and retain them in his files during the time he uses the 
cargo tank motor vehicle and for at least one year thereafter.

[Order 59-B, 30 FR 583, Jan. 16, 1965. Redesignated at 32 FR 5606, Apr. 
5, 1967]

    Editorial Note: For Federal Register citations affecting Sec. 
178.337-18, see the List of CFR Sections Affected, which appears in the 
Finding Aids section of the printed volume and at www.fdsys.gov.



Sec. 178.338  Specification MC-338; insulated cargo tank motor vehicle.



Sec. 178.338-1  General requirements.

    (a) For the purposes of this section--
    (1) Design pressure means the ``MAWP'' as used in Section VIII of 
the ASME Code (IBR, see Sec. 171.7 of this subchapter), and is the 
gauge pressure at the top of the tank.
    (2) Design service temperature means the coldest temperature for 
which the tank is suitable (see Sec. Sec. 173.318 (a)(1) and (f) of 
this subchapter).
    (b) Each cargo tank must consist of a suitably supported welded 
inner vessel enclosed within an outer shell or jacket, with insulation 
between the inner vessel and outer shell or jacket, and having piping, 
valves, supports and other appurtenances as specified in this 
subchapter. For the purpose of this specification, tank means inner 
vessel

[[Page 147]]

and jacket means either the outer shell or insulation cover.
    (c) Each tank must be designed, constructed, certified, and stamped 
in accordance with Section VIII of the ASME Code.
    (d) The exterior surface of the tank must be insulated with a 
material compatible with the lading.
    (1) Each cargo tank must have an insulation system that will prevent 
the tank pressure from exceeding the pressure relief valve set pressure 
within the specified holding time when the tank is loaded with the 
specific cryogenic liquid at the design conditions of--
    (i) The specified temperature and pressure of the cryogenic liquid, 
and
    (ii) The exposure of the filled cargo tank to an average ambient 
temperature of 85 [deg]F.
    (2) For a cargo tank used to transport oxygen, the insulation may 
not sustain combustion in a 99.5 percent oxygen atmosphere at 
atmospheric pressure when contacted with a continuously heated glowing 
platinum wire. The cargo tank must be marked in accordance with Sec. 
178.338-18(b)(7).
    (3) Each vacuum-insulated cargo tank must be provided with a 
connection for a vacuum gauge to indicate the absolute pressure within 
the insulation space.
    (e) The insulation must be completely covered by a metal jacket. The 
jacket or the insulation must be so constructed and sealed as to prevent 
moisture from coming into contact with the insulation (see Sec. 
173.318(a)(3) of this subchapter). Minimum metal thicknesses are as 
follows:

------------------------------------------------------------------------
                                             Jacket         Jacket not
                                            evacuated       evacuated
               Type metal               --------------------------------
                                          Gauge  Inches   Gauge   Inches
------------------------------------------------------------------------
Stainless steel........................      18  0.0428      22   0.0269
Low carbon mild steel..................      12  0.0946      14   0.0677
Aluminum...............................  ......  0.125   ......   0.1000
------------------------------------------------------------------------

    (f) An evacuated jacket must be in compliance with the following 
requirements:
    (1) The jacket must be designed to sustain a minimum critical 
collapsing pressure of 30 psig.
    (2) If the jacket also supports additional loads, such as the weight 
of the tank and lading, the combined stress, computed according to the 
formula in Sec. 178.338-3(b), may not exceed 25 percent of the minimum 
specified tensile strength.

[Amdt. 178-77, 48 FR 27703, June 16, 1983, as amended at 49 FR 24316, 
June 12, 1984; Amdt. 178-104, 59 FR 49135, Sept. 26, 1994; 66 FR 45387, 
Aug. 28, 2001; 68 FR 75754, Dec. 31, 2003]



Sec. 178.338-2  Material.

    (a) All material used in the construction of a tank and its 
appurtenances that may come in contact with the lading must be 
compatible with the lading to be transported. All material used for tank 
pressure parts must conform to the requirements in Section II of the 
ASME Code (IBR, see Sec. 171.7 of this subchapter). All material used 
for evacuated jacket pressure parts must conform to the chemistry and 
steelmaking practices of one of the material specifications of Section 
II of the ASME Code or the following ASTM Specifications (IBR, see Sec. 
171.7 of this subchapter): A 242, A 441, A 514, A 572, A 588, A 606, A 
633, A 715, A 1008/A 1008M, A 1011/A 1011M.
    (b) All tie-rods, mountings, and other appurtenances within the 
jacket and all piping, fittings and valves must be of material suitable 
for use at the lowest temperature to be encountered.
    (c) Impact tests are required on all tank materials, except 
materials that are excepted from impact testing by the ASME Code, and 
must be performed using the procedure prescribed in Section VIII of the 
ASME Code.
    (d) The direction of final rolling of the shell material must be the 
circumferential orientation of the tank shell.
    (e) Each tank constructed in accordance with part UHT in Section 
VIII of the ASME Code must be postweld heat treated as a unit after 
completion of all welds to the shell and heads. Other tanks must be 
postweld heat treated as required in Section VIII of the ASME Code. For 
all tanks the method must be as prescribed in the ASME Code. Welded 
attachments to pads may be made after postweld heat treatment.
    (f) The fabricator shall record the heat and slab numbers and the 
certified Charpy impact values of each plate used in the tank on a 
sketch showing the location of each plate in the shell and heads of the 
tank. A copy of the sketch must be provided to the owner

[[Page 148]]

of the cargo tank and a copy must be retained by the fabricator for at 
least five years and made available, upon request, to any duly 
identified representative of the Department.

(Approved by the Office of Management and Budget under control number 
2137-0017)

[Amdt. 178-77, 48 FR 27703 and 27713, June 16, 1983, as amended at 49 FR 
24316, June 12, 1984; 68 FR 19281, Apr. 18, 2003; 68 FR 75754, Dec. 31, 
2003; 70 FR 34076, June 13, 2005]



Sec. 178.338-3  Structural integrity.

    (a) General requirements and acceptance criteria. (1) Except as 
permitted in paragraph (d) of this section, the maximum calculated 
design stress at any point in the tank may not exceed the lesser of the 
maximum allowable stress value prescribed in section VIII of the ASME 
Code, or 25 percent of the tensile strength of the material used.
    (2) The relevant physical properties of the materials used in each 
tank may be established either by a certified test report from the 
material manufacturer or by testing in conformance with a recognized 
national standard. In either case, the ultimate tensile strength of the 
material used in the design may not exceed 120 percent of the minimum 
ultimate tensile strength specified in either the ASME Code or the ASTM 
standard to which the material is manufactured.
    (3) The maximum design stress at any point in the tank must be 
calculated separately for the loading conditions described in paragraphs 
(b), (c), and (d) of this section. Alternate test or analytical methods, 
or a combination thereof, may be used in lieu of the procedures 
described in paragraphs (b), (c), and (d) of this section, if the 
methods are accurate and verifiable.
    (4) Corrosion allowance material may not be included to satisfy any 
of the design calculation requirements of this section.
    (b) Static design and construction. (1) The static design and 
construction of each tank must be in accordance with appendix G in 
Section VIII of the ASME Code (IBR, see Sec. 171.7 of this subchapter). 
The tank design must include calculation of stress due to the design 
pressure, the weight of lading, the weight of structures supported by 
the tank wall, and the effect of temperature gradients resulting from 
lading and ambient temperature extremes. When dissimilar materials are 
used, their thermal coefficients must be used in calculation of the 
thermal stresses.
    (2) Stress concentrations in tension, bending, and torsion which 
occur at pads, cradles, or other supports must be considered in 
accordance with appendix G in Section VIII of the ASME Code.
    (c) Stresses resulting from static and dynamic loadings, or a 
combination thereof, are not uniform throughout the cargo tank motor 
vehicle. The following is a simplified procedure for calculating the 
effective stress in the tank resulting from static and dynamic loadings. 
The effective stress (the maximum principal stress at any point) must be 
determined by the following formula:

S = 0.5 (Sy + Sx) (0.25(Sy - Sx)\2\ + 
Ss2) \0.5\


Where:

    (1) S = effective stress at any given point under the most severe 
combination of static and dynamic loadings that can occur at the same 
time, in psi.
    (2) Sy = circumferential stress generated by internal and 
external pressure when applicable, in psi.
    (3) Sx = the net longitudinal stress, in psi, generated 
by the following loading conditions:
    (i) The longitudinal tensile stress generated by internal pressure;
    (ii) The tensile or compressive stress generated by the axial load 
resulting from a decelerative force applied independently to each 
suspension assembly at the road surface using applicable static loadings 
specified in Sec. 178.338-13 (b);
    (iii) The tensile or compressive stress generated by the bending 
moment resulting from a decelerative force applied independently to each 
suspension assembly at the road surface using applicable static loadings 
specified in Sec. 178.338-13 (b);
    (iv) The tensile or compressive stress generated by the axial load 
resulting from an accelerative force applied to the horizontal pivot of 
the fifth wheel supporting the vehicle using applicable static loadings 
specified in Sec. 178.338-13 (b);

[[Page 149]]

    (v) The tensile or compressive stress generated by the bending 
moment resulting from an accelerative force applied to the horizontal 
pivot of the fifth wheel supporting the vehicle using applicable static 
loadings specified in Sec. 178.338-13 (b); and
    (vi) The tensile or compressive stress generated by a bending moment 
produced by a vertical force using applicable static loadings specified 
in Sec. 178.338-13 (b).
    (4) Ss = The following shear stresses that apply, in 
psi,: The vectorial sum of the applicable shear stresses in the plane 
under consideration, including direct shear generated by the static 
vertical loading; direct lateral and torsional shear generated by a 
lateral accelerative force applied at the road surface, using applicable 
static loads specified in Sec. 178.338-13 (b)
    (d) In order to account for stresses due to impact in an accident, 
the design calculations for the tank shell and heads must include the 
load resulting from the design pressure in combination with the dynamic 
pressure resulting from a longitudinal deceleration of ``2g''. For this 
loading condition the stress value used may not exceed the lesser of the 
yield strength or 75 percent of the ultimate tensile strength of the 
material of construction. For a cargo tank constructed of stainless 
steel, the maximum design stress may not exceed 75 percent of the 
ultimate tensile strength of the type steel used.
    (e) The minimum thickness of the shell or heads of the tank must be 
0.187 inch for steel and 0.270 inch for aluminum. However, the minimum 
thickness for steel may be 0.110 inches provided the cargo tank is:
    (1) Vacuum insulated, or
    (2) Double walled with a load bearing jacket designed to carry a 
proportionate amount of structural loads prescribed in this section.
    (f) Where a tank support is attached to any part of the tank wall, 
the stresses imposed on the tank wall must meet the requirements in 
paragraph (a) of this section.
    (g) The design, construction and installation of an attachment, 
appurtenance to the cargo tank or structural support member between the 
cargo tank and the vehicle or suspension component or accident 
protection device must conform to the following requirements:
    (1) Structural members, the suspension subframe, accident protection 
structures and external circumferential reinforcement devices must be 
used as sites for attachment of appurtenances and other accessories to 
the cargo tank, when practicable.
    (2) A lightweight attachment to the cargo tank wall such as a 
conduit clip, brakeline clip, skirting structure, lamp mounting bracket, 
or placard holder must be of a construction having lesser strength than 
the cargo tank wall materials and may not be more than 72 percent of the 
thickness of the material to which it is attached. The lightweight 
attachment may be secured directly to the cargo tank wall if the device 
is designed and installed in such a manner that, if damaged, it will not 
affect the lading retention integrity of the tank. A lightweight 
attachment must be secured to the cargo tank shell or head by a 
continuous weld or in such a manner as to preclude formation of pockets 
that may become sites for corrosion. Attachments meeting the 
requirements of this paragraph are not authorized for cargo tanks 
constructed under part UHT in Section VIII of the ASME Code.
    (3) Except as prescribed in paragraphs (g)(1) and (g)(2) of this 
section, the welding of any appurtenance the cargo tank wall must be 
made by attachment of a mounting pad so that there will be no adverse 
effect upon the lading retention integrity of the cargo tank if any 
force less than that prescribed in paragraph (b)(1) of this section is 
applied from any direction. The thickness of the mounting pad may not be 
less than that of the shell or head to which it is attached, and not 
more than 1.5 times the shell or head thickness. However, a pad with a 
minimum thickness of 0.187 inch may be used when the shell or head 
thickness is over 0.187 inch. If weep holes or tell-tale holes are used, 
the pad must be drilled or punched at the lowest point before it is 
welded to the tank. Each pad must:
    (i) Be fabricated from material determined to be suitable for 
welding to both the cargo tank material and the

[[Page 150]]

material of the appurtenance or structural support member; a Design 
Certifying Engineer must make this determination considering chemical 
and physical properties of the materials and must specify filler 
material conforming to the requirements in Section IX of the ASME Code 
(IBR, see Sec. 171.7 of this subchapter).
    (ii) Be preformed to an inside radius no greater than the outside 
radius of the cargo tank at the attachment location.
    (iii) Extend at least 2 inches in each direction from any point of 
attachment of an appurtenance or structural support member. This 
dimension may be measured from the center of the attached structural 
member.
    (iv) Have rounded corners, or otherwise be shaped in a manner to 
minimize stress concentrations on the shell or head.
    (v) Be attached by continuous fillet welding. Any fillet weld 
discontinuity may only be for the purpose of preventing an intersection 
between the fillet weld and a tank or jacket seam weld.

[Amdt. 178-89, 55 FR 37057, Sept. 7, 1990, as amended by Amdt. 178-89, 
56 FR 27876, June 17, 1991; 56 FR 46354, Sept. 11, 1991; 68 FR 19281, 
Apr. 18, 2003; 68 FR 57633, Oct. 6, 2003; 68 FR 75754, Dec. 31, 2003]



Sec. 178.338-4  Joints.

    (a) All joints in the tank, and in the jacket if evacuated, must be 
as prescribed in Section VIII of the ASME Code (IBR, see Sec. 171.7 of 
this subchapter), except that a butt weld with one plate edge offset is 
not authorized.
    (b) Welding procedure and welder performance tests must be made in 
accordance with Section IX of the ASME Code. Records of the 
qualification must be retained by the tank manufacturer for at least 
five years and must be made available, upon request, to any duly 
identified representative of the Department, or the owner of the cargo 
tank.
    (c) All longitudinal welds in tanks and load bearing jackets must be 
located so as not to intersect nozzles or supports other than load rings 
and stiffening rings.
    (d) Substructures must be properly fitted before attachment and the 
welding sequence must minimize stresses due to shrinkage of welds.
    (e) Filler material containing more than 0.05 percent vanadium may 
not be used with quenched and tempered steel.
    (f) All tank nozzle-to-shell and nozzle-to-head welds must be full 
penetration welds.

(Approved by the Office of Management and Budget under control number 
2137-0017)

[Amdt. 178-77, 48 FR 27704 and 27713, June 16, 1983, as amended at 49 FR 
24316, June 12, 1984; 68 FR 75754, Dec. 31, 2003]



Sec. 178.338-5  Stiffening rings.

    (a) A tank is not required to be provided with stiffening rings, 
except as prescribed in Section VIII of the ASME Code (IBR, see Sec. 
171.7 of this subchapter).
    (b) If a jacket is evacuated, it must be constructed in compliance 
with Sec. 178.338-1(f). Stiffening rings may be used to meet these 
requirements.

[Amdt. 178-77, 48 FR 27704, June 16, 1983, as amended at 68 FR 75754, 
Dec. 31, 2003]



Sec. 178.338-6  Manholes.

    (a) Each tank in oxygen service must be provided with a manhole as 
prescribed in Section VIII of the ASME Code (IBR, see Sec. 171.7 of 
this subchapter).
    (b) Each tank having a manhole must be provided with a means of 
entrance and exit through the jacket, or the jacket must be marked to 
indicate the manway location on the tank.
    (c) A manhole with a bolted closure may not be located on the front 
head of the tank.

[Amdt. 178-77, 48 FR 27704, June 16, 1983, as amended at 49 FR 24316, 
June 12, 1984; 68 FR 75754, Dec. 31, 2003]



Sec. 178.338-7  Openings.

    (a) The inlet to the liquid product discharge opening of each tank 
intended for flammable ladings must be at the bottom centerline of the 
tank.
    (b) If the leakage of a single valve, except a pressure relief 
valve, pressure control valve, full trycock or gas phase manual vent 
valve, would permit loss of flammable material, an additional closure 
that is leak tight at the tank

[[Page 151]]

design pressure must be provided outboard of such valve.

[Amdt. 178-77, 48 FR 27704, June 16, 1983]



Sec. 178.338-8  Pressure relief devices, piping, valves, and fittings.

    (a) Pressure relief devices. Each tank pressure relief device must 
be designed, constructed, and marked in accordance with Sec. 173.318(b) 
of this subchapter.
    (b) Piping, valves, and fittings. (1) The burst pressure of all 
piping, pipe fittings, hoses and other pressure parts, except for pump 
seals and pressure relief devices, must be at least 4 times the design 
pressure of the tank. Additionally, the burst pressure may not be less 
than 4 times any higher pressure to which each pipe, pipe fitting, hose 
or other pressure part may be subjected to in service.
    (2) Pipe joints must be threaded, welded or flanged. If threaded 
pipe is used, the pipe and fittings must be Schedule 80 weight or 
heavier. Malleable metals must be used in the construction of valves and 
fittings. Where copper tubing is permitted, joints shall be brazed or be 
of equally strong metal union type. The melting point of the brazing 
materials may not be lower than 1000 [deg]F. The method of joining 
tubing may not reduce the strength of the tubing, such as by the cutting 
of threads.
    (3) Each hose coupling must be designed for a pressure of at least 
120 percent of the hose design pressure and so that there will be no 
leakage when connected.
    (4) Piping must be protected from damage due to thermal expansion 
and contraction, jarring, and vibration. Slip joints are not authorized 
for this purpose.
    (5) All piping, valves and fittings on a cargo tank must be proved 
free from leaks. This requirement is met when such piping, valves, and 
fittings have been tested after installation with gas or air and proved 
leak tight at not less than the design pressure marked on the cargo 
tank. This requirement is applicable to all hoses used in a cargo tank, 
except that hose may be tested before or after installation on the tank.
    (6) Each valve must be suitable for the tank design pressure at the 
tank design service temperature.
    (7) All fittings must be rated for the maximum tank pressure and 
suitable for the coldest temperature to which they will be subjected in 
actual service.
    (8) All piping, valves, and fittings must be grouped in the smallest 
practicable space and protected from damage as required by Sec. 
178.338-10.
    (9) When a pressure-building coil is used on a tank designed to 
handle oxygen or flammable ladings, the vapor connection to that coil 
must be provided with a valve or check valve as close to the tank shell 
as practicable to prevent the loss of vapor from the tank in case of 
damage to the coil. The liquid connection to that coil must also be 
provided with a valve.

[Amdt. 178-77, 48 FR 27704, June 16, 1983, as amended by Amdt. 178-89, 
54 FR 25019, June 12, 1989]



Sec. 178.338-9  Holding time.

    (a) ``Holding time'' is the time, as determined by testing, that 
will elapse from loading until the pressure of the contents, under 
equilibrium conditions, reaches the level of the lowest pressure control 
valve or pressure relief valve setting.
    (b) Holding time test. (1) The test to determine holding time must 
be performed by charging the tank with a cryogenic liquid having a 
boiling point, at a pressure of one atmosphere, absolute, no lower than 
the design service temperature of the tank. The tank must be charged to 
its maximum permitted filling density with that liquid and stabilized to 
the lowest practical pressure, which must be equal to or less than the 
pressure to be used for loading. The cargo tank together with its 
contents must then be exposed to ambient temperature.
    (2) The tank pressure and ambient temperature must be recorded at 3-
hour intervals until the pressure level of the contents reaches the set-
to-discharge pressure of the pressure control valve or pressure relief 
valve with the lowest setting. This total time lapse in hours represents 
the measured holding time at the actual average ambient temperature. 
This measured holding time for the test cryogenic liquid must be 
adjusted to an equivalent holding time for each cryogenic liquid that is

[[Page 152]]

to be identified on or adjacent to the specification plate, at an 
average ambient temperature of 85 [deg]F. This is the rated holding time 
(RHT). The marked rated holding time (MRHT) displayed on or adjacent to 
the specification plate (see Sec. 178.338-18(c)(10)) may not exceed 
this RHT.
    (c) Optional test regimen. (1) If more than one cargo tank is made 
to the same design, only one cargo tank must be subjected to the full 
holding time test at the time of manufacture. However, each subsequent 
cargo tank made to the same design must be performance tested during its 
first trip. The holding time determined in this test may not be less 
than 90 percent of the marked rated holding time. This test must be 
performed in accordance with Sec. Sec. 173.318(g)(3) and 177.840(h) of 
this subchapter, regardless of the classification of the cryogenic 
liquid.
    (2) Same design. The term ``same design'' as used in this section 
means cargo tanks made to the same design type. See Sec. 178.320(a) for 
definition of ``design type''.
    (3) For a cargo tank used in nonflammable cryogenic liquid service, 
in place of the holding time tests prescribed in paragraph (b) of this 
section, the marked rated holding time (MRHT) may be determined as 
follows:
    (i) While the cargo tank is stationary, the heat transfer rate must 
be determined by measuring the normal evaporation rate (NER) of the test 
cryogenic liquid (preferably the lading, where feasible) maintained at 
approximately one atmosphere. The calculated heat transfer rate must be 
determined from:

q = [n([Delta] h)(85-t1)] / [ts - tf]

Where:

q = calculated heat transfer rate to cargo tank with lading, Btu/hr.
n = normal evaporation rate (NER), which is the rate of evaporation, 
          determined by the test of a test cryogenic liquid in a cargo 
          tank maintained at a pressure of approximately one atmosphere, 
          absolute, lb/hr.
[Delta] h = latent heat of vaporization of test fluid at test pressure, 
          Btu/lb.
ts = average temperature of outer shell during test, [deg]F.
t1 = equilibrium temperature of lading at maximum loading 
          pressure, [deg]F.
tf = equilibrium temperature of test fluid at one atmosphere, 
          [deg]F.

    (ii) The rated holding time (RHT) must be calculated as follows:

RHT = [(U2 - U1) W] / q

Where:

RHT = rated holding time, in hours
U1 and U2 = internal energy for the combined 
          liquid and vapor lading at the pressure offered for 
          transportation, and the set pressure of the applicable 
          pressure control valve or pressure relief valve, respectively, 
          Btu/lb.
W = total weight of the combined liquid and vapor lading in the cargo 
          tank, pounds.
q = calculated heat transfer rate to cargo tank with lading, Btu/hr.

    (iii) The MRHT (see Sec. 178.338-18(b)(9) of this subchapter) may 
not exceed the RHT.

[Amdt. 178-77, 48 FR 27704, June 16, 1983; 48 FR 50442, Nov. 1, 1983, as 
amended at 49 FR 24316, June 12, 1984; 49 FR 43965, Nov. 1, 1984; 59 FR 
55173, Nov. 3, 1994; Amdt. 178-118, 61 FR 51340, Oct. 1, 1996; 68 FR 
57634, Oct. 6, 2003; 71 FR 54397, Sept. 14, 2006]



Sec. 178.338-10  Accident damage protection.

    (a) All valves, fittings, pressure relief devices and other 
accessories to the tank proper, which are not isolated from the tank by 
closed intervening shut-off valves or check valves, must be installed 
within the motor vehicle framework or within a suitable collision 
resistant guard or housing, and appropriate ventilation must be 
provided. Each pressure relief device must be protected so that in the 
event of the upset of the vehicle onto a hard surface, the device's 
opening will not be prevented and its discharge will not be restricted.
    (b) Each protective device or housing, and its attachment to the 
vehicle structure, must be designed to withstand static loading in any 
direction that it may be loaded as a result of front, rear, side, or 
sideswipe collision, or the overturn of the vehicle. The static loading 
shall equal twice the loaded weight of the tank and attachments. A 
safety factor of four, based on the tensile strength of the material, 
shall be used. The protective device or the housing must be made of 
steel at least \3/16\-inch thick, or other material of equivalent 
strength.

[[Page 153]]

    (c) Rear-end tank protection. Rear-end tank protections devices 
must:
    (1) Consist of at least one rear bumper designed to protect the 
cargo tank and piping in the event of a rear-end collision. The rear-end 
tank protection device design must transmit the force of the collision 
directly to the chassis of the vehicle. The rear-end tank protection 
device and its attachments to the chassis must be designed to withstand 
a load equal to twice the weight of the loaded cargo tank and 
attachments, using a safety factor of four based on the tensile strength 
of the materials used, with such load being applied horizontally and 
parallel to the major axis of the cargo tank. The rear-end tank 
protection device dimensions must meet the requirements of Sec. 393.86 
of this title and extend vertically to a height adequate to protect all 
valves and fittings located at the rear of the cargo tank from damage 
that could result in loss of lading; or
    (2) Conform to the requirements of Sec. 178.345-8(b).
    (d) Every part of the loaded cargo tank, and any associated valve, 
pipe, enclosure, or protective device or structure (exclusive of wheel 
assemblies), must be at least 14 inches above level ground.

[Amdt. 178-77, 48 FR 27705, June 16, 1983, as amended at 49 FR 24316, 
June 12, 1984; Amdt. 178-99, 58 FR 51534, Oct. 1, 1993; 68 FR 19282, 
Apr. 18, 2003; 68 FR 52371, Sept. 3, 2003]



Sec. 178.338-11  Discharge control devices.

    (a) Excess-flow valves are not required.
    (b) Each liquid filling and liquid discharge line must be provided 
with a shut-off valve located as close to the tank as practicable. 
Unless this valve is manually operable at the valve, the line must also 
have a manual shut-off valve.
    (c) Except for a cargo tank that is used to transport argon, carbon 
dioxide, helium, krypton, neon, nitrogen, xenon, or mixtures thereof, 
each liquid filling and liquid discharge line must be provided with an 
on-vehicle remotely controlled self-closing shutoff valve.
    (1) If pressure from a reservoir or from an engine-driven pump or 
compressor is used to open this valve, the control must be of fail-safe 
design and spring-biased to stop the admission of such pressure into the 
cargo tank. If the jacket is not evacuated, the seat of the valve must 
be inside the tank, in the opening nozzle or flange, or in a companion 
flange bolted to the nozzle. If the jacket is evacuated, the remotely 
controlled valve must be located as close to the tank as practicable.
    (2) Each remotely controlled shut off valve must be provided with 
on-vehicle remote means of automatic closure, both mechanical and 
thermal. One means may be used to close more than one remotely 
controlled valve. Cable linkage between closures and remote operators 
must be corrosion resistant and effective in all types of environment 
and weather. The thermal means must consist of fusible elements actuated 
at a temperature not exceeding 121 [deg]C (250 [deg]F), or equivalent 
devices. The loading/unloading connection area is where hoses are 
connected to the permanent metal piping. The number and location of 
remote operators and thermal devices shall be as follows:
    (i) On a cargo tank motor vehicle over 3,500 gallons water capacity, 
remote means of automatic closure must be installed at the ends of the 
cargo tank in at least two diagonally opposite locations. If the 
loading/unloading connection at the cargo tank is not in the general 
vicinity of one of these locations, at least one additional thermal 
device must be installed so that heat from a fire in the loading/
unloading connection area will activate the emergency control system.
    (ii) On a cargo tank motor vehicle of 3,500 gallons water capacity 
or less, at least one remote means of automatic closure must be 
installed on the end of the cargo tank farthest away from the loading/
unloading connection area. At least one thermal device must be installed 
so that heat from a fire in the loading/unloading connection area will 
activate the emergency control system.

[Amdt. 178-77, 48 FR 27705, June 16, 1983, as amended by Amdt. 178-105, 
59 FR 55173, Nov. 3, 1994; 60 FR 17402, Apr. 5, 1995; 68 FR 19282, Apr. 
18, 2003]

[[Page 154]]



Sec. 178.338-12  Shear section.

    Unless the valve is located in a rear cabinet forward of and 
protected by the bumper (see Sec. 178.338-10(c)), the design and 
installation of each valve, damage to which could result in loss of 
liquid or vapor, must incorporate a shear section or breakage groove 
adjacent to, and outboard of, the valve. The shear section or breakage 
groove must yield or break under strain without damage to the valve that 
would allow the loss of liquid or vapor. The protection specified in 
Sec. 178.338-10 is not a substitute for a shear section or breakage 
groove.

[Amdt. 178-77, 49 FR 24316, June 12, 1984]



Sec. 178.338-13  Supporting and anchoring.

    (a) On a cargo tank motor vehicle designed and constructed so that 
the cargo tank constitutes in whole or in part the structural member 
used in place of a motor vehicle frame, the cargo tank or the jacket 
must be supported by external cradles or by load rings. For a cargo tank 
mounted on a motor vehicle frame, the tank or jacket must be supported 
by external cradles, load rings, or longitudinal members. If cradles are 
used, they must subtend at least 120 degrees of the cargo tank 
circumference. The design calculations for the supports and load-bearing 
tank or jacket, and the support attachments must include beam stress, 
shear stress, torsion stress, bending moment, and acceleration stress 
for the loaded vehicle as a unit, using a safety factor of four, based 
on the tensile strength of the material, and static loading that uses 
the weight of the cargo tank and its attachments when filled to the 
design weight of the lading (see appendix G in Section VIII of the ASME 
Code) (IBR, see Sec. 171.7 of this subchapter), multiplied by the 
following factors. The effects of fatigue must also be considered in the 
calculations. Minimum static loadings must be as follows:
    (1) For a vacuum-insulated cargo tank--
    (i) Vertically downward of 2;
    (ii) Vertically upward of 2;
    (iii) Longitudinally of 2; and
    (iv) Laterally of 2.
    (2) For any other insulated cargo tank--
    (i) Vertically downward of 3;
    (ii) Vertically upward of 2;
    (iii) Longitudinally of 2; and
    (iv) Laterally of 2.
    (b) When a loaded tank is supported within the vacuum jacket by 
structural members, the design calculations for the tank and its 
structural members must be based on a safety factor of four and the 
tensile strength of the material at ambient temperature. The enhanced 
tensile strength of the material at actual operating temperature may be 
substituted for the tensile strength at ambient temperature to the 
extent recognized in the ASME Code for static loadings. Static loadings 
must take into consideration the weight of the tank and the structural 
members when the tank is filled to the design weight of lading (see 
Appendix G of Section VIII, Division 1 of the ASME Code), multiplied by 
the following factors. Static loadings must take into consideration the 
weight of the tank and the structural members when the tank is filled to 
the design weight of lading (see appendix G in Section VIII of the ASME 
Code), multiplied by the following factors. When load rings in the 
jacket are used for supporting the tank, they must be designed to carry 
the fully loaded tank at the specified static loadings, plus external 
pressure. Minimum static loadings must be as follows:
    (1) Vertically downward of 2;
    (2) Vertically upward of 1\1/2\;
    (3) Longitudinally of 1\1/2\; and, (4) Laterally of 1\1/2\.

[68 FR 19282, Apr. 18, 2003, as amended at 68 FR 75754, Dec. 31, 2003]



Sec. 178.338-14  Gauging devices.

    (a) Liquid level gauging devices. (1) Unless a cargo tank is 
intended to be filled by weight, it must be equipped with one or more 
gauging devices, which accurately indicate the maximum permitted liquid 
level at the loading pressure, in order to provide a minimum of two 
percent outage below the inlet of the pressure control valve or pressure 
relief valve at the condition of incipient opening of that valve. A 
fixed-length dip tube, a fixed trycock line, or a differential pressure 
liquid

[[Page 155]]

level gauge must be used as the primary control for filling. Other 
gauging devices, except gauge glasses, may be used, but not as the 
primary control for filling.
    (2) The design pressure of each liquid level gauging device must be 
at least that of the tank.
    (3) If a fixed length dip tube or trycock line gauging device is 
used, it must consist of a pipe or tube of small diameter equipped with 
a valve at or near the jacket and extending into the cargo tank to a 
specified filling height. The fixed height at which the tube ends in the 
cargo tank must be such that the device will function when the liquid 
reaches the maximum level permitted in loading.
    (4) The liquid level gauging device used as a primary control for 
filling must be designed and installed to accurately indicate the 
maximum filling level at the point midway of the tank both 
longitudinally and laterally.
    (b) Pressure gauges. Each cargo tank must be provided with a 
suitable pressure gauge indicating the lading pressure and located on 
the front of the jacket so it can be read by the driver in the rear view 
mirror. Each gauge must have a reference mark at the cargo tank design 
pressure or the set pressure of the pressure relief valve or pressure 
control valve, whichever is lowest.
    (c) Orifices. All openings for dip tube gauging devices and pressure 
gauges in flammable cryogenic liquid service must be restricted at or 
inside the jacket by orifices no larger than 0.060-inch diameter. 
Trycock lines, if provided, may not be greater than \1/2\-inch nominal 
pipe size.

[Amdt. 178-77, 48 FR 27706, June 16, 1983, as amended at 49 FR 24317, 
June 12, 1984]



Sec. 178.338-15  Cleanliness.

    A cargo tank constructed for oxygen service must be thoroughly 
cleaned to remove all foreign material in accordance with CGA G-4.1 
(IBR, see Sec. 171.7 of this subchapter). All loose particles from 
fabrication, such as weld beads, dirt, grinding wheel debris, and other 
loose materials, must be removed prior to the final closure of the 
manhole of the tank. Chemical or solvent cleaning with a material 
compatible with the intending lading must be performed to remove any 
contaminants likely to react with the lading.

[68 FR 75755, Dec. 31, 2003]



Sec. 178.338-16  Inspection and testing.

    (a) General. The material of construction of a tank and its 
appurtenances must be inspected for conformance to Section VIII of the 
ASME Code (IBR, see Sec. 171.7 of this subchapter). The tank must be 
subjected to either a hydrostatic or pneumatic test. The test pressure 
must be one and one-half times the sum of the design pressure, plus 
static head of lading, plus 101.3 kPa (14.7 psi) if subjected to 
external vacuum, except that for tanks constructed in accordance with 
Part UHT in Section VIII of the ASME Code the test pressure must be 
twice the design pressure.
    (b) Additional requirements for pneumatic test. A pneumatic test may 
be used in place of the hydrostatic test. Due regard for protection of 
all personnel should be taken because of the potential hazard involved 
in a pneumatic test. The pneumatic test pressure in the tank must be 
reached by gradually increasing the pressure to one-half of the test 
pressure. Thereafter, the test pressure must be increased in steps of 
approximately one-tenth of the test pressure until the required test 
pressure has been reached. Then the pressure must be reduced to a value 
equal to four-fifths of the test pressure and held for a sufficient time 
to permit inspection of the cargo tank for leaks.
    (c) Weld inspection. All tank shell or head welds subject to 
pressure shall be radiographed in accordance with Section VIII of the 
ASME Code. A tank which has been subjected to inspection by the magnetic 
particle method, the liquid penetrant method, or any method involving a 
material deposit on the interior tank surface, must be cleaned to remove 
any such residue by scrubbing or equally effective means, and all such 
residue and cleaning solution must be removed from the tank prior to 
final closure of the tank.
    (d) Defect repair. All cracks and other defects must be repaired as 
prescribed in Section VIII of the ASME Code. The welder and the welding 
procedure must be qualified in accordance with Section

[[Page 156]]

IX of the ASME Code (IBR, see Sec. 171.7 of this subchapter). After 
repair, the tank must again be postweld heat-treated, if such heat 
treatment was previously performed, and the repaired areas must be 
retested.
    (e) Verification must be made of the interior cleanliness of a tank 
constructed for oxygen service by means that assure that all 
contaminants that are likely to react with the lading have been removed 
as required by Sec. 178.338-15.

[Amdt. 178-77, 48 FR 27706, June 16, 1983, as amended at 49 FR 24317, 
June 12, 1984; 49 FR 42736, Oct. 24, 1984; 68 FR 75755, Dec. 31, 2003]



Sec. 178.338-17  Pumps and compressors.

    (a) Liquid pumps and gas compressors, if used, must be of suitable 
design, adequately protected against breakage by collision, and kept in 
good condition. They may be driven by motor vehicle power take-off or 
other mechanical, electrical, or hydraulic means. Unless they are of the 
centrifugal type, they shall be equipped with suitable pressure actuated 
by-pass valves permitting flow from discharge to suction to the tank.
    (b) A valve or fitting made of aluminum with internal rubbing or 
abrading aluminum parts that may come in contact with oxygen (cryogenic 
liquid) may not be installed on any cargo tank used to transport oxygen 
(cryogenic liquid) unless the parts are anodized in accordance with ASTM 
B 580 (IBR, see Sec. 171.7 of this subchapter).

[Amdt. 178-89, 54 FR 25020, June 12, 1989, as amended at 55 FR 37058, 
Sept. 7, 1990; 67 FR 61016, Sept. 27, 2002; 68 FR 75755, Dec. 31, 2003]



Sec. 178.338-18  Marking.

    (a) General. Each cargo tank certified after October 1, 2004 must 
have a corrosion-resistant metal name plate (ASME Plate) and 
specification plate permanently attached to the cargo tank by brazing, 
welding, or other suitable means on the left side near the front, in a 
place accessible for inspection. If the specification plate is attached 
directly to the cargo tank wall by welding, it must be welded to the 
tank before the cargo tank is postweld heat treated.
    (1) The plates must be legibly marked by stamping, embossing, or 
other means of forming letters into the metal of the plate, with the 
information required in paragraphs (b) and (c) of this section, in 
addition to that required by Section VIII of the ASME Code (IBR, see 
Sec. 171.7 of this subchapter), in characters at least \3/16\ inch high 
(parenthetical abbreviations may be used). All plates must be maintained 
in a legible condition.
    (2) Each insulated cargo tank must have additional plates, as 
described, attached to the jacket in the location specified unless the 
specification plate is attached to the chassis and has the information 
required in paragraphs (b) and (c) of this section.
    (3) The information required for both the name and specification 
plate may be displayed on a single plate. If the information required by 
this section is displayed on a plate required by Section VIII of the 
ASME Code, the information need not be repeated on the name and 
specification plates.
    (4) The specification plate may be attached to the cargo tank motor 
vehicle chassis rail by brazing, welding, or other suitable means on the 
left side near the front head, in a place accessible for inspection. If 
the specification plate is attached to the chassis rail, then the cargo 
tank serial number assigned by the cargo tank manufacturer must be 
included on the plate.
    (b) Name plate. The following information must be marked on the name 
plate in accordance with this section:
    (1) DOT-specification number MC 338 (DOT MC 338).
    (2) Original test date (Orig, Test Date).
    (3) MAWP in psig.
    (4) Cargo tank test pressure (Test P), in psig.
    (5) Cargo tank design temperature (Design Temp. Range) ---- [deg]F 
to ---- [deg]F.
    (6) Nominal capacity (Water Cap.), in pounds.
    (7) Maximum design density of lading (Max. Lading density), in 
pounds per gallon.
    (8) Material specification number--shell (Shell matl, yyy * * *), 
where ``yyy'' is replaced by the alloy designation and ``* * *'' is 
replaced by the alloy type.

[[Page 157]]

    (9) Material specification number--heads (Head matl. yyy * * *), 
where ``yyy'' is replaced by the alloy designation and ``* * *'' by the 
alloy type.

    Note: When the shell and heads materials are the same thickness, 
they may be combined, (Shell & head matl, yyy * * *).

    (10) Weld material (Weld matl.).
    (11) Minimum Thickness-shell (Min. Shell-thick), in inches. When 
minimum shell thicknesses are not the same for different areas, show 
(top ----, side ----, bottom ----, in inches).
    (12) Minimum thickness-heads (Min heads thick.), in inches.
    (13) Manufactured thickness-shell (Mfd. Shell thick.), top ----, 
side ----, bottom ----, in inches. (Required when additional thickness 
is provided for corrosion allowance.)
    (14) Manufactured thickness-heads (Mfd. Heads thick.), in inches. 
(Required when additional thickness is provided for corrosion 
allowance.)
    (15) Exposed surface area, in square feet.
    (c) Specification plate. The following information must be marked on 
the specification plate in accordance with this section:
    (1) Cargo tank motor vehicle manufacturer (CTMV mfr.).
    (2) Cargo tank motor vehicle certification date (CTMV cert. date).
    (3) Cargo tank manufacturer (CT mfr.).
    (4) Cargo tank date of manufacture (CT date of mfr.), month and 
year.
    (5) Maximum weight of lading (Max. Payload), in pounds.
    (6) Maximum loading rate in gallons per minute (Max. Load rate, 
GPM).
    (7) Maximum unloading rate in gallons per minute (Max Unload rate).
    (8) Lining materials (Lining), if applicable.
    (9) ``Insulated for oxygen service'' or ``Not insulated for oxygen 
service'' as appropriate.
    (10) Marked rated holding time for at least one cryogenic liquid, in 
hours, and the name of that cryogenic liquid (MRHT ---- hrs, name of 
cryogenic liquid). Marked rated holding marking for additional cryogenic 
liquids may be displayed on or adjacent to the specification plate.
    (11) Cargo tank serial number (CT serial), as assigned by cargo tank 
manufacturer, if applicable.

    Note 1 to paragraph (c): See Sec. 173.315(a) of this chapter 
regarding water capacity.
    Note 2 to paragraph (c): When the shell and head materials are the 
same thickness, they may be combined (Shell & head matl, yyy***).

    (d) The design weight of lading used in determining the loading in 
Sec. Sec. 178.338-3 (b), 178.338-10 (b) and (c), and 178.338-13 (b), 
must be shown as the maximum weight of lading marking required by 
paragraph (c) of this section.

[68 FR 19283, Apr. 18, 2003, as amended at 68 FR 57634, Oct. 6, 2003; 68 
FR 75755, Dec. 31, 2003]



Sec. 178.338-19  Certification.

    (a) At or before the time of delivery, the manufacturer of a cargo 
tank motor vehicle shall furnish to the owner of the completed vehicle 
the following:
    (1) The tank manufacturer's data report as required by the ASME Code 
(IBR, see Sec. 171.7 of this subchapter), and a certificate bearing the 
manufacturer's vehicle serial number stating that the completed cargo 
tank motor vehicle conforms to all applicable requirements of 
Specification MC 338, including Section VIII of the ASME Code (IBR, see 
Sec. 171.7 of this subchapter) in effect on the date (month, year) of 
certification. The registration numbers of the manufacturer, the Design 
Certifying Engineer, and the Registered Inspector, as appropriate, must 
appear on the certificates (see subpart F, part 107 in subchapter B of 
this chapter).
    (2) A photograph, pencil rub, or other facsimile of the plates 
required by paragraphs (a) and (b) of Sec. 178.338-18.
    (b) In the case of a cargo tank vehicle manufactured in two or more 
stages, each manufacturer who performs a manufacturing operation on the 
incomplete vehicle or portion thereof shall furnish to the succeeding 
manufacturer, at or before the time of delivery, a certificate covering 
the particular operation performed by that manufacturer, and any 
certificates received from previous manufacturers, Registered 
Inspectors, and Design Certifying Engineers. The certificates must 
include sufficient sketches, drawings,

[[Page 158]]

and other information to indicate the location, make, model and size of 
each valve and the arrangement of all piping associated with the tank. 
Each certificate must be signed by an official of the manufacturing firm 
responsible for the portion of the complete cargo tank vehicle 
represented thereby, such as basic tank fabrication, insulation, jacket, 
or piping. The final manufacturer shall furnish the owner with all 
certificates, as well as the documents required by paragraph (a) of this 
section.
    (c) The owner shall retain the data report, certificates, and 
related papers throughout his ownership of the cargo tank. In the event 
of change of ownership, the prior owner shall retain non-fading 
photographically reproduced copies of these documents for at least one 
year. Each operator using the cargo tank vehicle, if not the owner 
thereof, shall obtain a copy of the data report and the certificate or 
certificates and retain them during the time he uses the cargo tank and 
for at least one year thereafter.

(Approved by the Office of Management and Budget under control number 
2137-0017)

[Amdt. 178-77, 48 FR 27707 and 27713, June 16, 1983, as amended by Amdt. 
178-89, 55 FR 37058, Sept. 7, 1990; Amdt. 178-99, 58 FR 51534, Oct. 1, 
1993; 62 FR 51561, Oct. 1, 1997; 68 FR 75755, Dec. 31, 2003]



Sec. Sec. 178.340-178.343  [Reserved]



Sec. 178.345  General design and construction requirements applicable
to Specification DOT 406 (Sec. 178.346), DOT 407 (Sec. 178.347), 
and DOT 412 (Sec. 178.348) cargo tank motor vehicles.



Sec. 178.345-1  General requirements.

    (a) Specification DOT 406, DOT 407 and DOT 412 cargo tank motor 
vehicles must conform to the requirements of this section in addition to 
the requirements of the applicable specification contained in Sec. Sec. 
178.346, 178.347 or 178.348.
    (b) All specification requirements are minimum requirements.
    (c) Definitions. See Sec. 178.320(a) for the definition of certain 
terms used in Sec. Sec. 178.345, 178.346, 178.347, and 178.348. In 
addition, the following definitions apply to Sec. Sec. 178.345, 
178.346, 178.347, and 178.348:
    Appurtenance means any cargo tank accessory attachment that has no 
lading retention or containment function and provides no structural 
support to the cargo tank.
    Baffle means a non-liquid-tight transverse partition device that 
deflects, checks or regulates fluid motion in a tank.
    Bulkhead means a liquid-tight transverse closure at the ends of or 
between cargo tanks.
    Charging line means a hose, tube, pipe, or similar device used to 
pressurize a tank with material other than the lading.
    Companion flange means one of two mating flanges where the flange 
faces are in contact or separated only by a thin leak sealing gasket and 
are secured to one another by bolts or clamps.
    Connecting structure means the structure joining two cargo tanks.
    Constructed and certified in conformance with the ASME Code means 
the cargo tank is constructed and stamped in accordance with the ASME 
Code, and is inspected and certified by an Authorized Inspector.
    Constructed in accordance with the ASME Code means the cargo tank is 
constructed in accordance with the ASME Code with the authorized 
exceptions (see Sec. Sec. 178.346, 178.347, and 178.348) and is 
inspected and certified by a Registered Inspector.
    External self-closing stop-valve means a self-closing stop-valve 
designed so that the self-stored energy source is located outside the 
cargo tank and the welded flange.
    Extreme dynamic loading means the maximum single-acting loading a 
cargo tank motor vehicle may experience during its expected life, 
excluding accident loadings.
    Flange means the structural ring for guiding or attachment of a pipe 
or fitting with another flange (companion flange), pipe, fitting or 
other attachment.
    Inspection pressure means the pressure used to determine leak 
tightness of the cargo tank when testing with pneumatic pressure.
    Internal self-closing stop-valve means a self-closing stop-valve 
designed so that the self-stored energy source is located

[[Page 159]]

inside the cargo tank or cargo tank sump, or within the welded flange, 
and the valve seat is located within the cargo tank or within one inch 
of the external face of the welded flange or sump of the cargo tank.
    Lading means the hazardous material contained in a cargo tank.
    Loading/unloading connection means the fitting in the loading/
unloading line farthest from the loading/unloading outlet to which the 
loading/unloading hose or device is attached.
    Loading/unloading outlet means the cargo tank outlet used for normal 
loading/unloading operations.
    Loading/unloading stop-valve means the stop valve farthest from the 
cargo tank loading/unloading outlet to which the loading/unloading 
connection is attached.
    MAWP. See Sec. 178.320(a).
    Multi-specification cargo tank motor vehicle means a cargo tank 
motor vehicle equipped with two or more cargo tanks fabricated to more 
than one cargo tank specification.
    Normal operating loading means the loading a cargo tank motor 
vehicle may be expected to experience routinely in operation.
    Nozzle means the subassembly consisting of a pipe or tubular section 
with or without a welded or forged flange on one end.
    Outlet means any opening in the shell or head of a cargo tank, 
(including the means for attaching a closure), except that the following 
are not outlets: A threaded opening securely closed during 
transportation with a threaded plug or a threaded cap, a flanged opening 
securely closed during transportation with a bolted or welded blank 
flange, a manhole, or gauging devices, thermometer wells, and safety 
relief devices.
    Outlet stop-valve means the stop-valve at the cargo tank loading/
unloading outlet.
    Pipe coupling means a fitting with internal threads on both ends.
    Rear bumper means the structure designed to prevent a vehicle or 
object from under-riding the rear of a motor vehicle. See Sec. 393.86 
of this title.
    Rear-end tank protection device means the structure designed to 
protect a cargo tank and any lading retention piping or devices in case 
of a rear end collision.
    Sacrificial device means an element, such as a shear section, 
designed to fail under a load in order to prevent damage to any lading 
retention part or device. The device must break under strain at no more 
than 70 percent of the strength of the weakest piping element between 
the cargo tank and the sacrificial device. Operation of the sacrificial 
device must leave the remaining piping and its attachment to the cargo 
tank intact and capable of retaining lading.
    Self-closing stop-valve means a stop-valve held in the closed 
position by means of self-stored energy, which opens only by application 
of an external force and which closes when the external force is 
removed.
    Shear section means a sacrificial device fabricated in such a manner 
as to abruptly reduce the wall thickness of the adjacent piping or valve 
material by at least 30 percent.
    Shell means the circumferential portion of a cargo tank defined by 
the basic design radius or radii excluding the closing heads.
    Stop-valve means a valve that stops the flow of lading.
    Sump means a protrusion from the bottom of a cargo tank shell 
designed to facilitate complete loading and unloading of lading.
    Tank means a container, consisting of a shell and heads, that forms 
a pressure tight vessel having openings designed to accept pressure 
tight fittings or closures, but excludes any appurtenances, 
reinforcements, fittings, or closures.
    Test pressure means the pressure to which a tank is subjected to 
determine pressure integrity.
    Toughness of material means the capability of a material to absorb 
the energy represented by the area under the stress strain curve 
(indicating the energy absorbed per unit volume of the material) up to 
the point of rupture.
    Vacuum cargo tank means a cargo tank that is loaded by reducing the 
pressure in the cargo tank to below atmospheric pressure.
    Variable specification cargo tank means a cargo tank that is 
constructed in accordance with one specification,

[[Page 160]]

but which may be altered to meet another specification by changing 
relief device, closures, lading discharge devices, and other lading 
retention devices.
    Void means the space between tank heads or bulkheads and a 
connecting structure.
    Welded flange means a flange attached to the tank by a weld joining 
the tank shell to the cylindrical outer surface of the flange, or by a 
fillet weld joining the tank shell to a flange shaped to fit the shell 
contour.
    (d) A manufacturer of a cargo tank must hold a current ASME 
certificate of authorization and must be registered with the Department 
in accordance with part 107, subpart F of this chapter.
    (e) All construction must be certified by an Authorized Inspector or 
by a Registered Inspector as applicable to the cargo tank.
    (f) Each cargo tank must be designed and constructed in conformance 
with the requirements of the applicable cargo tank specification. Each 
DOT 412 cargo tank with a ``MAWP'' greater than 15 psig, and each DOT 
407 cargo tank with a maximum allowable working pressure greater than 35 
psig must be ``constructed and certified in conformance with Section 
VIII of the ASME Code'' (IBR, see Sec. 171.7 of this subchapter) except 
as limited or modified by the applicable cargo tank specification. Other 
cargo tanks must be ``constructed in accordance with Section VIII of the 
ASME Code,'' except as limited or modified by the applicable cargo tank 
specification.
    (g) Requirements relating to parts and accessories on motor 
vehicles, which are contained in part 393 of the Federal Motor Carrier 
Safety Regulations of this title, are incorporated into these 
specifications.
    (h) Any additional requirements prescribed in part 173 of this 
subchapter that pertain to the transportation of a specific lading are 
incorporated into these specifications.
    (i) Cargo tank motor vehicle composed of multiple cargo tanks. (1) A 
cargo tank motor vehicle composed of more than one cargo tank may be 
constructed with the cargo tanks made to the same specification or to 
different specifications. Each cargo tank must conform in all respects 
with the specification for which it is certified.
    (2) The strength of the connecting structure joining multiple cargo 
tanks in a cargo tank motor vehicle must meet the structural design 
requirements in Sec. 178.345-3. Any void within the connecting 
structure must be equipped with a drain located on the bottom centerline 
that is accessible and kept open at all times. For carbon steel, self-
supporting cargo tanks, the drain configuration may consist of a single 
drain of at least 1.0 inch diameter, or two or more drains of at least 
0.5 inch diameter, 6.0 inches apart, one of which is located as close to 
the bottom centerline as practicable. Vapors trapped in a void within 
the connecting structure must be allowed to escape to the atmosphere 
either through the drain or a separate vent.
    (j) Variable specification cargo tank. A cargo tank that may be 
physically altered to conform to another cargo tank specification must 
have the required physical alterations to convert from one specification 
to another clearly indicated on the variable specification plate.

[Amdt. 178-89, 54 FR 25020, June 12, 1989, as amended at 55 FR 37058, 
Sept. 7, 1990; Amdt. 178-105, 59 FR 55173, Nov. 3, 1994; Amdt. 178-118, 
61 FR 51340, Oct. 1, 1996; 66 FR 45387, 45389, Aug. 28, 2001; 68 FR 
19283, Apr. 18, 2003; 68 FR 52371, Sept. 3, 2003; 68 FR 75755, Dec. 31, 
2003; 70 FR 56099, Sept. 23, 2005; 76 FR 43532, July 20, 2011]



Sec. 178.345-2  Material and material thickness.

    (a) All material for shell, heads, bulkheads, and baffles must 
conform to Section II of the ASME Code (IBR, see Sec. 171.7 of this 
subchapter) except as follows:
    (1) The following steels are also authorized for cargo tanks 
``constructed in accordance with the ASME Code'', Section VIII.

ASTM A 569
ASTM A 570
ASTM A 572
ASTM A 622
ASTM A 656
ASTM A 715
ASTM A 1008/ A 1008M, ASTM A 1011/A 1011M

    (2) Aluminum alloys suitable for fusion welding and conforming with 
the

[[Page 161]]

0, H32 or H34 tempers of one of the following ASTM specifications may be 
used for cargo tanks ``constructed in accordance with the ASME Code'':

ASTM B-209 Alloy 5052
ASTM B-209 Alloy 5086
ASTM B-209 Alloy 5154
ASTM B-209 Alloy 5254
ASTM B-209 Alloy 5454
ASTM B-209 Alloy 5652


All heads, bulkheads and baffles must be of 0 temper (annealed) or 
stronger tempers. All shell materials shall be of H 32 or H 34 tempers 
except that the lower ultimate strength tempers may be used if the 
minimum shell thicknesses in the tables are increased in inverse 
proportion to the lesser ultimate strength.
    (b) Minimum thickness. The minimum thickness for the shell and heads 
(or baffles and bulkheads when used as tank reinforcement) must be no 
less than that determined under criteria for minimum thickness specified 
in Sec. 178.320(a).
    (c) Corrosion or abrasion protection. When required by 49 CFR part 
173 for a particular lading, a cargo tank or a part thereof, subject to 
thinning by corrosion or mechanical abrasion due to the lading, must be 
protected by providing the tank or part of the tank with a suitable 
increase in thickness of material, a lining or some other suitable 
method of protection.
    (1) Corrosion allowance. Material added for corrosion allowance need 
not be of uniform thickness if different rates of attack can reasonably 
be expected for various areas of the cargo tank.
    (2) Lining. Lining material must consist of a nonporous, homogeneous 
material not less elastic than the parent metal and substantially immune 
to attack by the lading. The lining material must be bonded or attached 
by other appropriate means to the cargo tank wall and must be 
imperforate when applied. Any joint or seam in the lining must be made 
by fusing the materials together, or by other satisfactory means.

[Amdt. 178-89, 54 FR 25021, June 12, 1989, as amended at 55 FR 37059, 
Sept. 7, 1990; 56 FR 27876, June 17, 1991; Amdt. 178-97, 57 FR 45465, 
Oct. 1, 1992; Amdt. 178-118, 61 FR 51341, Oct. 1, 1996; 68 FR 19283, 
Apr. 18, 2003; 68 FR 75755, Dec. 31, 2003; 70 FR 34076, June 13, 2005]



Sec. 178.345-3  Structural integrity.

    (a) General requirements and acceptance criteria. (1) The maximum 
calculated design stress at any point in the cargo tank wall may not 
exceed the maximum allowable stress value prescribed in Section VIII of 
the ASME Code (IBR, see Sec. 171.7 of this subchapter), or 25 percent 
of the tensile strength of the material used at design conditions.
    (2) The relevant physical properties of the materials used in each 
cargo tank may be established either by a certified test report from the 
material manufacturer or by testing in conformance with a recognized 
national standard. In either case, the ultimate tensile strength of the 
material used in the design may not exceed 120 percent of the minimum 
ultimate tensile strength specified in either the ASME Code or the ASTM 
standard to which the material is manufactured.
    (3) The maximum design stress at any point in the cargo tank must be 
calculated separately for the loading conditions described in paragraphs 
(b) and (c) of this section. Alternate test or analytical methods, or a 
combination thereof, may be used in place of the procedures described in 
paragraphs (b) and (c) of this section, if the methods are accurate and 
verifiable. TTMA RP 96-01, Structural Integrity of DOT 406, DOT 407, and 
DOT 412 Cylindrical Cargo Tanks, may be used as guidance in performing 
the calculations.
    (4) Corrosion allowance material may not be included to satisfy any 
of the design calculation requirements of this section.
    (b) ASME Code design and construction. The static design and 
construction of each cargo tank must be in accordance with Section VIII 
of the ASME Code. The cargo tank design must include calculation of 
stresses generated by the MAWP, the weight of the lading, the weight of 
structures

[[Page 162]]

supported by the cargo tank wall and the effect of temperature gradients 
resulting from lading and ambient temperature extremes. When dissimilar 
materials are used, their thermal coefficients must be used in the 
calculation of thermal stresses.
    (1) Stress concentrations in tension, bending and torsion which 
occur at pads, cradles, or other supports must be considered in 
accordance with appendix G in Section VIII of the ASME Code.
    (2) Longitudinal compressive buckling stress for ASME certified 
vessels must be calculated using paragraph UG-23(b) in Section VIII of 
the ASME Code. For cargo tanks not required to be certified in 
accordance with the ASME Code, compressive buckling stress may be 
calculated using alternative analysis methods which are accurate and 
verifiable. When alternative methods are used, calculations must include 
both the static loads described in this paragraph and the dynamic loads 
described in paragraph (c) of this section.
    (3) Cargo tank designers and manufacturers must consider all of the 
conditions specified in Sec. 173.33(c) of this subchapter when matching 
a cargo tank's performance characteristic to the characteristic of each 
lading transported.
    (c) Shell design. Shell stresses resulting from static or dynamic 
loadings, or combinations thereof, are not uniform throughout the cargo 
tank motor vehicle. The vertical, longitudinal, and lateral normal 
operating loadings can occur simultaneously and must be combined. The 
vertical, longitudinal and lateral extreme dynamic loadings occur 
separately and need not be combined.
    (1) Normal operating loadings. The following procedure addresses 
stress in the cargo tank shell resulting from normal operating loadings. 
The effective stress (the maximum principal stress at any point) must be 
determined by the following formula:

S = 0.5(Sy + Sx) [0.25(Sy-Sx)\2\ + 
SS2]\0.5\


Where:
    (i) S = effective stress at any given point under the combination of 
static and normal operating loadings that can occur at the same time, in 
psi.
    (ii) Sy = circumferential stress generated by the MAWP 
and external pressure, when applicable, plus static head, in psi.
    (iii) Sx = The following net longitudinal stress 
generated by the following static and normal operating loading 
conditions, in psi:
    (A) The longitudinal stresses resulting from the MAWP and external 
pressure, when applicable, plus static head, in combination with the 
bending stress generated by the static weight of the fully loaded cargo 
tank motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall;
    (B) The tensile or compressive stress resulting from normal 
operating longitudinal acceleration or deceleration. In each case, the 
forces applied must be 0.35 times the vertical reaction at the 
suspension assembly, applied at the road surface, and as transmitted to 
the cargo tank wall through the suspension assembly of a trailer during 
deceleration; or the horizontal pivot of the truck tractor or converter 
dolly fifth wheel, or the drawbar hinge on the fixed dolly during 
acceleration; or anchoring and support members of a truck during 
acceleration and deceleration, as applicable. The vertical reaction must 
be calculated based on the static weight of the fully loaded cargo tank 
motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall. The following loadings must be 
included:
    (1) The axial load generated by a decelerative force;
    (2) The bending moment generated by a decelerative force;
    (3) The axial load generated by an accelerative force; and
    (4) The bending moment generated by an accelerative force; and
    (C) The tensile or compressive stress generated by the bending 
moment resulting from normal operating vertical accelerative force equal 
to 0.35 times the vertical reaction at the suspension assembly of a 
trailer; or the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or anchoring and support members of a truck, as applicable. 
The vertical reaction must be calculated

[[Page 163]]

based on the static weight of the fully loaded cargo tank motor vehicle, 
all structural elements, equipment and appurtenances supported by the 
cargo tank wall.
    (iv) SS = The following shear stresses generated by the 
following static and normal operating loading conditions, in psi:
    (A) The static shear stress resulting from the vertical reaction at 
the suspension assembly of a trailer, and the horizontal pivot of the 
upper coupler (fifth wheel) or turntable; or anchoring and support 
members of a truck, as applicable. The vertical reaction must be 
calculated based on the static weight of the fully loaded cargo tank 
motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall;
    (B) The vertical shear stress generated by a normal operating 
accelerative force equal to 0.35 times the vertical reaction at the 
suspension assembly of a trailer; or the horizontal pivot of the upper 
coupler (fifth wheel) or turntable; or anchoring and support members of 
a truck, as applicable. The vertical reaction must be calculated based 
on the static weight of the fully loaded cargo tank motor vehicle, all 
structural elements, equipment and appurtenances supported by the cargo 
tank wall;
    (C) The lateral shear stress generated by a normal operating lateral 
accelerative force equal to 0.2 times the vertical reaction at each 
suspension assembly of a trailer, applied at the road surface, and as 
transmitted to the cargo tank wall through the suspension assembly of a 
trailer, and the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or anchoring and support members of a truck, as applicable. 
The vertical reaction must be calculated based on the static weight of 
the fully loaded cargo tank motor vehicle, all structural elements, 
equipment and appurtenances supported by the cargo tank wall; and
    (D) The torsional shear stress generated by the same lateral forces 
as described in paragraph (c)(1)(iv)(C) of this section.
    (2) Extreme dynamic loadings. The following procedure addresses 
stress in the cargo tank shell resulting from extreme dynamic loadings. 
The effective stress (the maximum principal stress at any point) must be 
determined by the following formula:

S = 0.5(Sy + Sx) [0.25(Sy - Sx)\2\ + 
SS\2\]\0.5\


Where:

    (i) S = effective stress at any given point under a combination of 
static and extreme dynamic loadings that can occur at the same time, in 
psi.
    (ii) Sy = circumferential stress generated by MAWP and 
external pressure, when applicable, plus static head, in psi.
    (iii) Sx = the following net longitudinal stress 
generated by the following static and extreme dynamic loading 
conditions, in psi:
    (A) The longitudinal stresses resulting from the MAWP and external 
pressure, when applicable, plus static head, in combination with the 
bending stress generated by the static weight of the fully loaded cargo 
tank motor vehicle, all structural elements, equipment and appurtenances 
supported by the tank wall;
    (B) The tensile or compressive stress resulting from extreme 
longitudinal acceleration or deceleration. In each case the forces 
applied must be 0.7 times the vertical reaction at the suspension 
assembly, applied at the road surface, and as transmitted to the cargo 
tank wall through the suspension assembly of a trailer during 
deceleration; or the horizontal pivot of the truck tractor or converter 
dolly fifth wheel, or the drawbar hinge on the fixed dolly during 
acceleration; or the anchoring and support members of a truck during 
acceleration and deceleration, as applicable. The vertical reaction must 
be calculated based on the static weight of the fully loaded cargo tank 
motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall. The following loadings must be 
included:
    (1) The axial load generated by a decelerative force;
    (2) The bending moment generated by a decelerative force;
    (3) The axial load generated by an accelerative force; and
    (4) The bending moment generated by an accelerative force; and

[[Page 164]]

    (C) The tensile or compressive stress generated by the bending 
moment resulting from an extreme vertical accelerative force equal to 
0.7 times the vertical reaction at the suspension assembly of a trailer, 
and the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or the anchoring and support members of a truck, as 
applicable. The vertical reaction must be calculated based on the static 
weight of the fully loaded cargo tank motor vehicle, all structural 
elements, equipment and appurtenances supported by the cargo tank wall.
    (iv) SS = The following shear stresses generated by 
static and extreme dynamic loading conditions, in psi:
    (A) The static shear stress resulting from the vertical reaction at 
the suspension assembly of a trailer, and the horizontal pivot of the 
upper coupler (fifth wheel) or turntable; or anchoring and support 
members of a truck, as applicable. The vertical reaction must be 
calculated based on the static weight of the fully loaded cargo tank 
motor vehicle, all structural elements, equipment and appurtenances 
supported by the cargo tank wall;
    (B) The vertical shear stress generated by an extreme vertical 
accelerative force equal to 0.7 times the vertical reaction at the 
suspension assembly of a trailer, and the horizontal pivot of the upper 
coupler (fifth wheel) or turntable; or anchoring and support members of 
a truck, as applicable. The vertical reaction must be calculated based 
on the static weight of the fully loaded cargo tank motor vehicle, all 
structural elements, equipment and appurtenances supported by the cargo 
tank wall;
    (C) The lateral shear stress generated by an extreme lateral 
accelerative force equal to 0.4 times the vertical reaction at the 
suspension assembly of a trailer, applied at the road surface, and as 
transmitted to the cargo tank wall through the suspension assembly of a 
trailer, and the horizontal pivot of the upper coupler (fifth wheel) or 
turntable; or anchoring and support members of a truck, as applicable. 
The vertical reaction must be calculated based on the static weight of 
the fully loaded cargo tank motor vehicle, all structural elements, 
equipment and appurtenances supported by the cargo tank wall; and
    (D) The torsional shear stress generated by the same lateral forces 
as described in paragraph (c)(2)(iv)(C) of this section.
    (d) In no case may the minimum thickness of the cargo tank shells 
and heads be less than that prescribed in Sec. 178.346-2, Sec. 
178.347-2, or Sec. 178.348-2, as applicable.
    (e) For a cargo tank mounted on a frame or built with integral 
structural supports, the calculation of effective stresses for the 
loading conditions in paragraph (c) of this section may include the 
structural contribution of the frame or the integral structural 
supports.
    (f) The design, construction, and installation of an attachment, 
appurtenance to a cargo tank, structural support member between the 
cargo tank and the vehicle or suspension component must conform to the 
following requirements:
    (1) Structural members, the suspension sub-frame, accident 
protection structures and external circumferential reinforcement devices 
must be used as sites for attachment of appurtenances and other 
accessories to the cargo tank, when practicable.
    (2) A lightweight attachment to a cargo tank wall such as a conduit 
clip, brake line clip, skirting structure, lamp mounting bracket, or 
placard holder must be of a construction having lesser strength than the 
cargo tank wall materials and may not be more than 72 percent of the 
thickness of the material to which it is attached. The lightweight 
attachment may be secured directly to the cargo tank wall if the device 
is designed and installed in such a manner that, if damaged, it will not 
affect the lading retention integrity of the tank. A lightweight 
attachment must be secured to the cargo tank shell or head by continuous 
weld or in such a manner as to preclude formation of pockets which may 
become sites for corrosion.
    (3) Except as prescribed in paragraphs (f)(1) and (f)(2) of this 
section, the welding of any appurtenance to the cargo tank wall must be 
made by attachment of a mounting pad so that there will be no adverse 
effect upon the

[[Page 165]]

lading retention integrity of the cargo tank if any force less than that 
prescribed in paragraph (b)(1) of this section is applied from any 
direction. The thickness of the mounting pad may not be less than that 
of the shell or head to which it is attached, and not more than 1.5 
times the shell or head thickness. However, a pad with a minimum 
thickness of 0.187 inch may be used when the shell or head thickness is 
over 0.187 inch. If weep holes or tell-tale holes are used, the pad must 
be drilled or punched at the lowest point before it is welded to the 
tank. Each pad must:
    (i) Be fabricated from material determined to be suitable for 
welding to both the cargo tank material and the material of the 
appurtenance or structural support member; a Design Certifying Engineer 
must make this determination considering chemical and physical 
properties of the materials and must specify filler material conforming 
to the requirements of the ASME Code (incorporated by reference; see 
Sec. 171.7 of this subchapter).
    (ii) Be preformed to an inside radius no greater than the outside 
radius of the cargo tank at the attachment location.
    (iii) Extend at least 2 inches in each direction from any point of 
attachment of an appurtenance or structural support member. This 
dimension may be measured from the center of the structural member 
attached.
    (iv) Have rounded corners, or otherwise be shaped in a manner to 
minimize stress concentrations on the shell or head.
    (v) Be attached by continuous fillet welding. Any fillet weld 
discontinuity may only be for the purpose of preventing an intersection 
between the fillet weld and the tank or jacket seam weld.

[Amdt. 178-89, 55 FR 37059, Sept. 7, 1990, as amended by Amdt. 178-89, 
56 FR 27876, June 17, 1991; Amdt. 178-104, 59 FR 49135, Sept. 26, 1994; 
Amdt. 178-105, 59 FR 55173, 55174 and 55175, Nov. 3, 1994; 60 FR 17402, 
Apr. 5, 1995; Amdt. 178-118, 61 FR 51341, Oct. 1, 1996; 65 FR 58631, 
Sept. 29, 2000; 68 FR 19283, Apr. 18, 2003; 68 FR 75755, Dec. 31, 2003; 
74 FR 16143, Apr. 9, 2009]



Sec. 178.345-4  Joints.

    (a) All joints between the cargo tank shell, heads, baffles, baffle 
attaching rings, and bulkheads must be welded in conformance with 
Section VIII of the ASME Code (IBR, see Sec. 171.7 of this subchapter).
    (b) Where practical all welds must be easily accessible for 
inspection.

[Amdt. 178-89, 54 FR 25022, June 12, 1989, as amended by Amdt. 178-118, 
61 FR 51341, Oct. 1, 1996; 68 FR 75756, Dec. 31, 2003]



Sec. 178.345-5  Manhole assemblies.

    (a) Each cargo tank with capacity greater than 400 gallons must be 
accessible through a manhole at least 15 inches in diameter.
    (b) Each manhole, fill opening and washout assembly must be 
structurally capable of withstanding, without leakage or permanent 
deformation that would affect its structural integrity, a static 
internal fluid pressure of at least 36 psig, or cargo tank test 
pressure, whichever is greater. The manhole assembly manufacturer shall 
verify compliance with this requirement by hydrostatically testing at 
least one percent (or one manhole closure, whichever is greater) of all 
manhole closures of each type produced each 3 months, as follows:
    (1) The manhole, fill opening, or washout assembly must be tested 
with the venting devices blocked. Any leakage or deformation that would 
affect the product retention capability of the assembly shall constitute 
a failure.
    (2) If the manhole, fill opening, or washout assembly tested fails, 
then five more covers from the same lot must be tested. If one of these 
five covers fails, then all covers in the lot from which the tested 
covers were selected are to be 100% tested or rejected for service.
    (c) Each manhole, filler and washout cover must be fitted with a 
safety device that prevents the cover from opening fully when internal 
pressure is present.
    (d) Each manhole and fill cover must be secured with fastenings that 
will prevent opening of the covers as a result of vibration under normal 
transportation conditions or shock impact

[[Page 166]]

due to a rollover accident on the roadway or shoulder where the fill 
cover is not struck by a substantial obstacle.
    (e) On cargo tank motor vehicles manufactured after October 1, 2004, 
each manhole assembly must be permanently marked on the outside by 
stamping or other means in a location visible without opening the 
manhole assembly or fill opening, with:
    (1) Manufacturer's name;
    (2) Test pressure ---- psig;
    (3) A statement certifying that the manhole cover meets the 
requirements in Sec. 178.345-5.
    (f) All components mounted on a manhole cover that form part of the 
lading retention structure of the cargo tank wall must withstand the 
same static internal fluid pressure as that required for the manhole 
cover. The component manufacturer shall verify compliance using the same 
test procedure and frequency of testing as specified in Sec. 178.345-
5(b).

[Amdt. 178-89, 54 FR 25022, June 12, 1989, as amended by Amdt. 178-105, 
59 FR 55175, Nov. 3, 1994; 68 FR 19284, Apr. 18, 2003; 74 FR 16144, Apr. 
9, 2009]



Sec. 178.345-6  Supports and anchoring.

    (a) A cargo tank with a frame not integral to the cargo tank must 
have the tank secured by restraining devices to eliminate any motion 
between the tank and frame that may abrade the tank shell due to the 
stopping, starting, or turning of the cargo tank motor vehicle. The 
design calculations of the support elements must include the stresses 
indicated in Sec. 178.345-3(b) and as generated by the loads described 
in Sec. 178.345-3(c). Such restraining devices must be readily 
accessible for inspection and maintenance, except that insulation and 
jacketing are permitted to cover the restraining devices.
    (b) A cargo tank designed and constructed so that it constitutes, in 
whole or in part, the structural member used in lieu of a frame must be 
supported in such a manner that the resulting stress levels in the cargo 
tank do not exceed those specified in Sec. 178.345-3(a). The design 
calculations of the support elements must include the stresses indicated 
in Sec. 178.345-3(b) and as generated by the loads described in Sec. 
178.345-3(c).

[Amdt. 178-89, 54 FR 25023, June 12, 1989, as amended by Amdt. 178-105, 
59 FR 55175, Nov. 3, 1994; Amdt. 178-118, 61 FR 51341, Oct. 1, 1996]



Sec. 178.345-7  Circumferential reinforcements.

    (a) A cargo tank with a shell thickness of less than \3/8\ inch must 
be circumferentially reinforced with bulkheads, baffles, ring 
stiffeners, or any combination thereof, in addition to the cargo tank 
heads.
    (1) Circumferential reinforcement must be located so that the 
thickness and tensile strength of the shell material in combination with 
the frame and reinforcement produces structural integrity at least equal 
to that prescribed in Sec. 178.345-3 and in such a manner that the 
maximum unreinforced portion of the shell does not exceed 60 inches. For 
cargo tanks designed to be loaded by vacuum, spacing of circumferential 
reinforcement may exceed 60 inches provided the maximum unreinforced 
portion of the shell conforms with the requirements in Section VIII of 
the ASME Code (IBR, see Sec. 171.7 of this subchapter).
    (2) Where circumferential joints are made between conical shell 
sections, or between conical and cylindrical shell sections, and the 
angle between adjacent sections is less than 160 degrees, 
circumferential reinforcement must be located within one inch of the 
shell joint, unless otherwise reinforced with structural members capable 
of maintaining shell stress levels authorized in Sec. 178.345-3. When 
the joint is formed by the large ends of adjacent conical shell 
sections, or by the large end of a conical shell and a cylindrical shell 
section, this angle is measured inside the shell; when the joint is 
formed by the small end of a conical shell section and a cylindrical 
shell section, it is measured outside the shell.
    (b) Except for doubler plates and knuckle pads, no reinforcement may 
cover any circumferential joint.
    (c) When a baffle or baffle attachment ring is used as a 
circumferential reinforcement member, it must produce structural 
integrity at least equal to that prescribed in Sec. 178.345-3

[[Page 167]]

and must be circumferentially welded to the cargo tank shell. The welded 
portion may not be less than 50 percent of the total circumference of 
the cargo tank and the length of any unwelded space on the joint may not 
exceed 40 times the shell thickness unless reinforced external to the 
cargo tank.
    (d) When a ring stiffener is used as a circumferential reinforcement 
member, whether internal or external, reinforcement must be continuous 
around the circumference of the cargo tank shell and must be in 
accordance with the following:
    (1) The section modulus about the neutral axis of the ring section 
parallel to the shell must be at least equal to that derived from the 
applicable formula:

I/C = 0.00027WL, for MS, HSLA and SS; or
I/C = 0.000467WL, for aluminum alloys;

Where:

I/C = Section modulus in inches \3\
W = Tank width, or diameter, inches
L = Spacing of ring stiffener, inches; i.e., the maximum longitudinal 
          distance from the midpoint of the unsupported shell on one 
          side of the ring stiffener to the midpoint of the unsupported 
          shell on the opposite side of the ring stiffener.

    (2) If a ring stiffener is welded to the cargo tank shell, a portion 
of the shell may be considered as part of the ring section for purposes 
of computing the ring section modulus. This portion of the shell may be 
used provided at least 50 percent of the total circumference of the 
cargo tank is welded and the length of any unwelded space on the joint 
does not exceed 40 times the shell thickness. The maximum portion of the 
shell to be used in these calculations is as follows:

------------------------------------------------------------------------
  Number of circumferential ring
     stiffener-to-shell welds              J \1\          Shell section
------------------------------------------------------------------------
1................................  ....................  20t
2................................  Less than 20t.......  20t+J
2................................  20t or more.........  40t
------------------------------------------------------------------------
\1\ where:
t=Shell thickness, inches;
J=Longitudinal distance between parallel circumferential ring stiffener-
  to-shell welds.

    (3) When used to meet the vacuum requirements of this section, ring 
stiffeners must be as prescribed in Section VIII of the ASME Code.
    (4) If configuration of internal or external ring stiffener encloses 
an air space, this air space must be arranged for venting and be 
equipped with drainage facilities which must be kept operative at all 
times.
    (5) Hat shaped or open channel ring stiffeners which prevent visual 
inspection of the cargo tank shell are prohibited on cargo tank motor 
vehicles constructed of carbon steel.

[Amdt. 178-89, 55 FR 37060, Sept. 7, 1990, as amended by Amdt. 178-89, 
56 FR 27876, June 17, 1991; 56 FR 46354, Sept. 11, 1991; Amdt. 178-104, 
59 FR 49135, Sept. 26, 1994; Amdt. 178-118, 61 FR 51341, Oct. 1, 1996; 
68 FR 75756, Dec. 31, 2003]



Sec. 178.345-8  Accident damage protection.

    (a) General. Each cargo tank motor vehicle must be designed and 
constructed in accordance with the requirements of this section and the 
applicable individual specification to minimize the potential for the 
loss of lading due to an accident.
    (1) Any dome, sump, or washout cover plate projecting from the cargo 
tank wall that retains lading in any tank orientation, must be as strong 
and tough as the cargo tank wall and have a thickness at least equal to 
that specified by the appropriate cargo tank specification. Any such 
projection located in the lower \1/3\ of the tank circumference (or 
cross section perimeter for non-circular cargo tanks) that extends more 
than half its diameter at the point of attachment to the tank or more 
than 4 inches from the cargo tank wall, or located in the upper \2/3\ of 
the tank circumference (or cross section perimeter for non-circular 
cargo tanks) that extends more than \1/4\ its diameter or more than 2 
inches from the point of attachment to the tank must have accident 
damage protection devices that are:
    (i) As specified in this section;
    (ii) 125 percent as strong as the otherwise required accident damage 
protection device; or
    (iii) Attached to the cargo tank in accordance with the requirements 
of paragraph (a)(3) of this section.
    (2) Outlets, valves, closures, piping, or any devices that if 
damaged in an accident could result in a loss of lading

[[Page 168]]

from the cargo tank must be protected by accident damage protection 
devices as specified in this section.
    (3) Accident damage protection devices attached to the wall of a 
cargo tank must be able to withstand or deflect away from the cargo tank 
the loads specified in this section. They must be designed, constructed 
and installed so as to maximize the distribution of loads to the cargo 
tank wall and to minimize the possibility of adversely affecting the 
lading retention integrity of the cargo tank. Accident induced stresses 
resulting from the appropriate accident damage protection device 
requirements in combination with the stresses from the cargo tank 
operating at the MAWP may not result in a cargo tank wall stress greater 
than the ultimate strength of the material of construction using a 
safety factor of 1.3. Deformation of the protection device is acceptable 
provided the devices being protected are not damaged when loads 
specified in this section are applied.
    (4) Any piping that extends beyond an accident damage protection 
device must be equipped with a stop-valve and a sacrificial device such 
as a shear section. The sacrificial device must be located in the piping 
system outboard of the stop-valve and within the accident damage 
protection device to prevent any accidental loss of lading. The device 
must break at no more than 70 percent of the load that would be required 
to cause the failure of the protected lading retention device, part or 
cargo tank wall. The failure of the sacrificial device must leave the 
protected lading retention device and its attachment to the cargo tank 
wall intact and capable of retaining product.
    (5) Minimum road clearance. The minimum road clearance of any cargo 
tank motor vehicle component or protection device located between any 
two adjacent axles on a vehicle or vehicle combination must be at least 
one-half inch for each foot separating the component or device from the 
nearest axle of the adjacent pair, but in no case less than twelve (12) 
inches, except that the minimum road clearance for landing gear or other 
attachments within ten (10) feet of an axle must be no less than ten 
(10) inches. These measurements must be calculated at the gross vehicle 
weight rating of the cargo tank motor vehicle.
    (b) Each outlet, projection or piping located in the lower \1/3\ of 
the cargo tank circumference (or cross section perimeter for non-
circular cargo tanks) that could be damaged in an accident that may 
result in the loss of lading must be protected by a bottom damage 
protection device, except as provided by paragraph (a)(1) of this 
section and Sec. 173.33(e) of this subchapter. Outlets, projections and 
piping may be grouped or clustered together and protected by a single 
protection device.
    (1) Any bottom damage protection device must be able to withstand a 
force of 155,000 pounds (based on the ultimate strength of the material) 
from the front, side, or rear, uniformly distributed over each surface 
of the device, over an area not to exceed 6 square feet, and a width not 
to exceed 6 feet. Suspension components and structural mounting members 
may be used to provide all, or part, of this protection. The device must 
extend no less than 6 inches beyond any component that may contain 
lading in transit.
    (2) A lading discharge opening equipped with an internal self-
closing stop-valve need not conform to paragraph (b)(1) of this section 
provided it is protected so as to reasonably assure against the 
accidental loss of lading. This protection must be provided by a 
sacrificial device located outboard of each internal self-closing stop-
valve and within 4 inches of the major radius of the cargo tank shell or 
within 4 inches of a sump, but in no case more than 8 inches from the 
major radius of the tank shell. The device must break at no more than 70 
percent of the load that would be required to cause the failure of the 
protected lading retention device, part or cargo tank wall. The failure 
of the sacrificial device must leave the protected lading retention 
device or part and its attachment to the cargo tank wall intact and 
capable of retaining product.
    (c) Each closure for openings, including but not limited to the 
manhole, filling or inspection openings, and each valve, fitting, 
pressure relief device, vapor recovery stop valve or lading retaining 
fitting located in the upper \2/3\

[[Page 169]]

of a cargo tank circumference (or cross section perimeter for non-
circular tanks) must be protected by being located within or between 
adjacent rollover damage protection devices, or by being 125 percent of 
the strength that would be provided by the otherwise required damage 
protection device.
    (1) A rollover damage protection device on a cargo tank motor 
vehicle must be designed and installed to withstand loads equal to twice 
the weight of the loaded cargo tank motor vehicle applied as follows: 
normal to the cargo tank shell (perpendicular to the cargo tank 
surface); and tangential (perpendicular to the normal load) from any 
direction. The stresses shall not exceed the ultimate strength of the 
material of construction. These design loads may be considered to be 
uniformly distributed and independently applied. If more than one 
rollover protection device is used, each device must be capable of 
carrying its proportionate share of the required loads and in each case 
at least one-fourth the total tangential load. The design must be proven 
capable of carrying the required loads by calculations, tests or a 
combination of tests and calculations.
    (2) A rollover damage protection device that would otherwise allow 
the accumulation of liquid on the top of the cargo tank, must be 
provided with a drain that directs the liquid to a safe point of 
discharge away from any structural component of the cargo tank motor 
vehicle.
    (d) Rear-end tank protection. Each cargo tank motor vehicle must be 
provided with a rear-end tank protection device to protect the cargo 
tank and piping in the event of a rear-end collision and reduce the 
likelihood of damage that could result in the loss of lading. Nothing in 
this paragraph relieves the manufacturer of responsibility for complying 
with the requirements of Sec. 393.86 of this title and, if applicable, 
paragraph (b) of this section. The rear-end tank protection device must 
conform to the following requirements:
    (1) The rear-end cargo tank protection device must be designed so 
that it can deflect at least 6 inches horizontally forward with no 
contact between any part of the cargo tank motor vehicle which contains 
lading during transit and with any part of the rear-end protection 
device, or with a vertical plane passing through the outboard surface of 
the protection device.
    (2) The dimensions of the rear-end cargo tank protection device 
shall conform to the following:
    (i) The bottom surface of the rear-end protection device must be at 
least 4 inches below the lower surface of any part at the rear of the 
cargo tank motor vehicle which contains lading during transit and not 
more than 60 inches from the ground when the vehicle is empty.
    (ii) The maximum width of a notch, indentation, or separation 
between sections of a rear-end cargo tank protection device may not 
exceed 24 inches. A notched, indented, or separated rear-end protection 
device may be used only when the piping at the rear of the cargo tank is 
equipped with a sacrificial device outboard of a shut-off valve.
    (iii) The widest part of the motor vehicle at the rear may not 
extend more than 18 inches beyond the outermost ends of the device or 
(if separated) devices on either side of the vehicle.
    (3) The structure of the rear-end protection device and its 
attachment to the vehicle must be designed to satisfy the conditions 
specified in paragraph (d)(1) of this section when subjected to an 
impact of the cargo tank motor vehicle at rated payload, at a 
deceleration of 2 ``g''. Such impact must be considered as being 
uniformly applied in the horizontal plane at an angle of 10 degrees or 
less to the longitudinal axis of the vehicle.
    (e) Longitudinal deceleration protection. In order to account for 
stresses due to longitudinal impact in an accident, the cargo tank shell 
and heads must be able to withstand the load resulting from the design 
pressure in combination with the dynamic pressure resulting from a 
longitudinal deceleration of 2 ``g''. For this loading condition, the 
allowable stress value used may not exceed the ultimate strength of the 
material of construction using a safety factor of 1.3. Performance 
testing, analytical methods, or a combination thereof, may be used to 
prove this capability provided the methods are accurate and verifiable. 
For cargo tanks with internal baffles,

[[Page 170]]

the decelerative force may be reduced by 0.25 ``g'' for each baffle 
assembly, but in no case may the total reduction in decelerative force 
exceed 1.0 ``g''.

[Amdt. 178-89, 54 FR 25023, June 12, 1989, as amended at 55 FR 37061, 
Sept. 7, 1990; Amdt. 178-105, 59 FR 55175, Nov. 3, 1994; Amdt. 178-118, 
61 FR 51341, Oct. 1, 1996; 68 FR 19284, Apr. 18, 2003]



Sec. 178.345-9  Pumps, piping, hoses and connections.

    (a) Suitable means must be provided during loading or unloading 
operations to ensure that pressure within a cargo tank does not exceed 
test pressure.
    (b) Each hose, piping, stop-valve, lading retention fitting and 
closure must be designed for a bursting pressure of the greater of 100 
psig or four times the MAWP.
    (c) Each hose coupling must be designed for a bursting pressure of 
the greater of 120 psig or 4.8 times the MAWP of the cargo tank, and 
must be designed so that there will be no leakage when connected.
    (d) Suitable provision must be made to allow for and prevent damage 
due to expansion, contraction, jarring, and vibration. Slip joints may 
not be used for this purpose in the lading retention system.
    (e) Any heating device, when installed, must be so constructed that 
the breaking of its external connections will not cause leakage of the 
cargo tank lading.
    (f) Any gauging, loading or charging device, including associated 
valves, must be provided with an adequate means of secure closure to 
prevent leakage.
    (g) The attachment and construction of each loading/unloading or 
charging line must be of sufficient strength, or be protected by a 
sacrificial device, such that any load applied by loading/unloading or 
charging lines connected to the cargo tank cannot cause damage resulting 
in loss of lading from the cargo tank.
    (h) Use of a nonmetallic pipe, valve or connection that is not as 
strong and heat resistant as the cargo tank material is authorized only 
if such attachment is located outboard of the lading retention system.

[Amdt. 178-89, 54 FR 25025, June 12, 1989, as amended at 55 FR 37061, 
Sept. 7, 1990, Amdt. 178-89, 56 FR 27877, June 17, 1991; Amdt. 178-118, 
61 FR 51341, Oct. 1, 1996]



Sec. 178.345-10  Pressure relief.

    (a) Each cargo tank must be equipped to relieve pressure and vacuum 
conditions in conformance with this section and the applicable 
individual specification. The pressure and vacuum relief system must be 
designed to operate and have sufficient capacity to prevent cargo tank 
rupture or collapse due to over-pressurization or vacuum resulting from 
loading, unloading, or from heating and cooling of lading. Pressure 
relief systems are not required to conform to the ASME Code.
    (b) Type and construction of relief systems and devices. (1) Each 
cargo tank must be provided with a primary pressure relief system 
consisting of one or more reclosing pressure relief valves. A secondary 
pressure relief system consisting of another pressure relief valve in 
parallel with the primary pressure relief system may be used to augment 
the total venting capacity of the cargo tank. Non-reclosing pressure 
relief devices are not authorized in any cargo tank except when in 
series with a reclosing pressure relief device. Gravity actuated 
reclosing valves are not authorized on any cargo tank.
    (2) When provided by Sec. 173.33(c)(1)(iii) of this subchapter, 
cargo tanks may be equipped with a normal vent. Such vents must be set 
to open at not less than 1 psig and must be designed to prevent loss of 
lading through the device in case of vehicle overturn.
    (3) Each pressure relief system must be designed to withstand 
dynamic pressure surges in excess of the design set pressure as 
specified in paragraphs (b)(3) (i) and (ii) of this section. Set 
pressure is a function of MAWP as set forth in paragraph (d) of this 
section.
    (i) Each pressure relief device must be able to withstand dynamic 
pressure surge reaching 30 psig above the design set pressure and 
sustained above the set pressure for at least 60 milliseconds with a 
total volume of liquid released

[[Page 171]]

not exceeding one gallon before the relief device recloses to a leak-
tight condition. This requirement must be met regardless of vehicle 
orientation. This capability must be demonstrated by testing. An 
acceptable method is outlined in TTMA RP No. 81-97 ``Performance of 
Spring Loaded Pressure Relief Valves on MC 306, MC 307, MC 312, DOT 406, 
DOT 407, and DOT 412 Tanks'' (incorporated by reference; see Sec. 171.7 
of this subchapter).
    (ii) After August 31, 1995, each pressure relief device must be able 
to withstand a dynamic pressure surge reaching 30 psig above the design 
set pressure and sustained above the design set pressure for at least 60 
milliseconds with a total volume of liquid released not exceeding 1 L 
before the relief valve recloses to a leak-tight condition. This 
requirement must be met regardless of vehicle orientation. This 
capability must be demonstrated by testing. TTMA RP No. 81, cited in 
paragraph (b)(3)(i) of this section, is an acceptable test procedure.
    (4) Each reclosing pressure relief valve must be constructed and 
installed in such a manner as to prevent unauthorized adjustment of the 
relief valve setting.
    (5) No shut-off valve or other device that could prevent venting 
through the pressure relief system may be installed in a pressure relief 
system.
    (6) The pressure relief system must be mounted, shielded and 
drainable so as to minimize the accumulation of material that could 
impair the operation or discharge capability of the system by freezing, 
corrosion or blockage.
    (c) Location of relief devices. Each pressure relief device must 
communicate with the vapor space above the lading as near as practicable 
to the center of the vapor space. For example, on a cargo tank designed 
to operate in a level attitude, the device should be positioned at the 
horizontal and transverse center of the cargo tank; on cargo tanks 
sloped to the rear, the device should be located in the forward half of 
the cargo tank. The discharge from any device must be unrestricted. 
Protective devices which deflect the flow of vapor are permissible 
provided the required vent capacity is maintained.
    (d) Settings of pressure relief system. The set pressure of the 
pressure relief system is the pressure at which it starts to open, 
allowing discharge.
    (1) Primary pressure relief system. The set pressure of each primary 
relief valve must be no less than 120 percent of the MAWP, and no more 
than 132 percent of the MAWP. The valve must reclose at not less than 
108 percent of the MAWP and remain closed at lower pressures.
    (2) Secondary pressure relief system. The set pressure of each 
pressure relief valve used as a secondary relief device must be not less 
than 120 percent of the MAWP.
    (e) Venting capacity of pressure relief systems. The pressure relief 
system (primary and secondary, including piping) must have sufficient 
venting capacity to limit the cargo tank internal pressure to not more 
than the cargo tank test pressure. The total venting capacity, rated at 
not more than the cargo tank test pressure, must be at least that 
specified in table I, except as provided in Sec. 178.348-4.

                Table I--Minimum Emergency Vent Capacity
          [In cubic feet free air/hour at 60 [deg]F and 1 atm.]
------------------------------------------------------------------------
                                                              Cubic feet
                Exposed area in square feet                    free air
                                                               per hour
------------------------------------------------------------------------
20.........................................................       15,800
30.........................................................       23,700
40.........................................................       31,600
50.........................................................       39,500
60.........................................................       47,400
70.........................................................       55,300
80.........................................................       63,300
90.........................................................       71,200
100........................................................       79,100
120........................................................       94,900
140........................................................      110,700
160........................................................      126,500
180........................................................      142,300
200........................................................      158,100
225........................................................      191,300
250........................................................      203,100
275........................................................      214,300
300........................................................      225,100
350........................................................      245,700
400........................................................      265,000
450........................................................      283,200
500........................................................      300,600
550........................................................      317,300
600........................................................      333,300
650........................................................      348,800
700........................................................      363,700
750........................................................      378,200
800........................................................      392,200
850........................................................      405,900
900........................................................      419,300

[[Page 172]]

 
950........................................................      432,300
1,000......................................................      445,000
------------------------------------------------------------------------
Note 1: Interpolate for intermediate sizes.

    (1) Primary pressure relief system. Unless otherwise specified in 
the applicable individual specification, the primary relief system must 
have a minimum venting capacity of 12,000 SCFH per 350 square feet of 
exposed cargo tank area, but in any case at least one fourth the 
required total venting capacity for the cargo tank.
    (2) Secondary pressure relief system. If the primary pressure relief 
system does not provide the required total venting capacity, additional 
capacity must be provided by a secondary pressure relief system.
    (f) Certification of pressure relief devices. The manufacturer of 
any pressure relief device, including valves, frangible (rupture) disks, 
vacuum vents and combination devices must certify that the device model 
was designed and tested in accordance with this section and the 
appropriate cargo tank specification. The certificate must contain 
sufficient information to describe the device and its performance. The 
certificate must be signed by a responsible official of the manufacturer 
who approved the flow capacity certification.
    (g) Rated flow capacity certification test. Each pressure relief 
device model must be successfully flow capacity certification tested 
prior to first use. Devices having one design, size and set pressure are 
considered to be one model. The testing requirements are as follows:
    (1) At least 3 devices of each specific model must be tested for 
flow capacity at a pressure not greater than the test pressure of the 
cargo tank. For a device model to be certified, the capacities of the 
devices tested must fall within a range of plus or minus 5 percent of 
the average for the devices tested.
    (2) The rated flow capacity of a device model may not be greater 
than 90 percent of the average value for the devices tested.
    (3) The rated flow capacity derived for each device model must be 
certified by a responsible official of the device manufacturer.
    (h) Marking of pressure relief devices. Each pressure relief device 
must be permanently marked with the following:
    (1) Manufacturer's name;
    (2) Model number;
    (3) Set pressure, in psig; and
    (4) Rated flow capacity, in SCFH at the rating pressure, in psig.

[Amdt. 178-89, 54 FR 25025, June 12, 1989, as amended at 55 FR 21038, 
May 22, 1990; 55 FR 37062, Sept. 7, 1990; Amdt. 178-89, 56 FR 27877, 
June 17, 1991; Amdt. 178-105, 59 FR 55175, Nov. 3, 1994; Amdt. 178-118, 
61 FR 51341, Oct. 1, 1996; 65 FR 58631, Sept. 29, 2000; 66 FR 45389, 
Aug. 28, 2001; 68 FR 19284, Apr. 18, 2003]



Sec. 178.345-11  Tank outlets.

    (a) General. As used in this section, ``loading/unloading outlet'' 
means any opening in the cargo tank wall used for loading or unloading 
of lading, as distinguished from outlets such as manhole covers, vents, 
vapor recovery devices, and similar closures. Cargo tank outlets, 
closures and associated piping must be protected in accordance with 
Sec. 178.345-8.
    (b) Each cargo tank loading/unloading outlet must be equipped with 
an internal self-closing stop-valve, or alternatively, with an external 
stop-valve located as close as practicable to the cargo tank wall. Each 
cargo tank loading/unloading outlet must be in accordance with the 
following provisions:
    (1) Each loading/unloading outlet must be fitted with a self-closing 
system capable of closing all such outlets in an emergency within 30 
seconds of actuation. During normal operations the outlets may be closed 
manually. The self-closing system must be designed according to the 
following:
    (i) Each self-closing system must include a remotely actuated means 
of closure located more than 10 feet from the loading/unloading outlet 
where vehicle length allows, or on the end of the cargo tank farthest 
away from the

[[Page 173]]

loading/unloading outlet. The actuating mechanism must be corrosion-
resistant and effective in all types of environment and weather.
    (ii) If the actuating system is accidentally damaged or sheared off 
during transportation, each loading/unloading outlet must remain 
securely closed and capable of retaining lading.
    (iii) When required by part 173 of this subchapter for materials 
which are flammable, pyrophoric, oxidizing, or Division 6.1 (poisonous 
liquid) materials, the remote means of closure must be capable of 
thermal activation. The means by which the self-closing system is 
thermally activated must be located as close as practicable to the 
primary loading/unloading connection and must actuate the system at a 
temperature not over 250 [deg]F. In addition, outlets on these cargo 
tanks must be capable of being remotely closed manually or mechanically.
    (2) Bottom loading outlets which discharge lading into the cargo 
tank through fixed internal piping above the maximum liquid level of the 
cargo tank need not be equipped with a self-closing system.
    (c) Any loading/unloading outlet extending beyond an internal self-
closing stop-valve, or beyond the innermost external stop-valve which is 
part of a self-closing system, must be fitted with another stop-valve or 
other leak-tight closure at the end of such connection.
    (d) Each cargo tank outlet that is not a loading/unloading outlet 
must be equipped with a stop-valve or other leak-tight closure located 
as close as practicable to the cargo tank outlet. Any connection 
extending beyond this closure must be fitted with another stop-valve or 
other leak-tight closure at the end of such connection.

[Amdt. 178-89, 56 FR 27877, June 17, 1991, as amended by Amdt. 178-97, 
57 FR 45465, Oct. 1, 1992; Amdt. 178-118, 61 FR 51341, Oct. 1, 1996]



Sec. 178.345-12  Gauging devices.

    Each cargo tank, except a cargo tank intended to be filled by 
weight, must be equipped with a gauging device that indicates the 
maximum permitted liquid level to within 0.5 percent of the nominal 
capacity as measured by volume or liquid level. Gauge glasses are not 
permitted.

[Amdt. 178-89, 55 FR 37062, Sept. 7, 1990, as amended by Amdt. 178-118, 
61 FR 51342, Oct. 1, 1996]



Sec. 178.345-13  Pressure and leakage tests.

    (a) Each cargo tank must be pressure and leakage tested in 
accordance with this section and Sec. Sec. 178.346-5, 178.347-5, or 
178.348-5.
    (b) Pressure test. Each cargo tank or cargo tank compartment must be 
tested hydrostatically or pneumatically. Each cargo tank of a multi-
cargo tank motor vehicle must be tested with the adjacent cargo tanks 
empty and at atmospheric pressure. Each closure, except pressure relief 
devices and loading/unloading venting devices rated at less than the 
prescribed test pressure, must be in place during the test. If the 
venting device is not removed during the test, such device must be 
rendered inoperative by a clamp, plug or other equally effective 
restraining device, which may not prevent the detection of leaks, or 
damage the device. Restraining devices must be removed immediately after 
the test is completed.
    (1) Hydrostatic method. Each cargo tank, including its domes, must 
be filled with water or other liquid having similar viscosity, the 
temperature of which may not exceed 100 [deg]F. The cargo tank must then 
be pressurized as prescribed in the applicable specification. The 
pressure must be gauged at the top of the cargo tank. The prescribed 
test pressure must be maintained for at least 10 minutes during which 
time the cargo tank must be inspected for leakage, bulging, or other 
defect.
    (2) Pneumatic method. A pneumatic test may be used in place of the 
hydrostatic test. However, pneumatic pressure testing may involve higher 
risk than hydrostatic testing. Therefore, suitable safeguards must be 
provided to protect personnel and facilities should failure occur during 
the test. The cargo tank must be pressurized with air or an inert gas. 
Test pressure must be reached gradually by increasing the pressure to 
one half of test pressure. Thereafter, the pressure must be increased in 
steps of approximately one tenth of the test pressure until test

[[Page 174]]

pressure is reached. Test pressure must be held for at least 5 minutes. 
The pressure must then be reduced to the inspection pressure which must 
be maintained while the entire cargo tank surface is inspected for 
leakage and other sign of defects. The inspection method must consist of 
coating all joints and fittings with a solution of soap and water or 
other equally sensitive method.
    (c) Leakage test. The cargo tank with all its accessories in place 
and operable must be leak tested at not less than 80 percent of tank's 
MAWP with the pressure maintained for at least 5 minutes.
    (d) Any cargo tank that leaks, bulges or shows any other sign of 
defect must be rejected. Rejected cargo tanks must be suitably repaired 
and retested successfully prior to being returned to service. The retest 
after any repair must use the same method of test under which the cargo 
tank was originally rejected.

[Amdt. 178-89, 54 FR 25026, June 12, 1989, as amended at 55 FR 37063, 
Sept. 7, 1990; Amdt. 178-105, 59 FR 55176, Nov. 3, 1994; Amdt. 178-118, 
61 FR 51342, Oct. 1, 1996; 65 FR 58631, Sept. 29, 2000; 68 FR 19284, 
Apr. 18, 2003]



Sec. 178.345-14  Marking.

    (a) General. The manufacturer shall certify that each cargo tank 
motor vehicle has been designed, constructed and tested in accordance 
with the applicable Specification DOT 406, DOT 407 or DOT 412 
(Sec. Sec. 178.345, 178.346, 178.347, 178.348) cargo tank requirements 
and, when applicable, with Section VIII of the ASME Code (IBR, see Sec. 
171.7 of this subchapter). The certification shall be accomplished by 
marking the cargo tank as prescribed in paragraphs (b) and (c) of this 
section, and by preparing the certificate prescribed in Sec. 178.345-
15. Metal plates prescribed by paragraphs (b), (c), (d) and (e) of this 
section, must be permanently attached to the cargo tank or its integral 
supporting structure, by brazing, welding or other suitable means. These 
plates must be affixed on the left side of the vehicle near the front of 
the cargo tank (or the frontmost cargo tank of a multi-cargo tank motor 
vehicle), in a place readily accessible for inspection. The plates must 
be permanently and plainly marked in English by stamping, embossing or 
other means in characters at least \3/16\ inch high. The information 
required by paragraphs (b) and (c) of this section may be combined on 
one specification plate.
    (b) Nameplate. Each cargo tank must have a corrosion resistant 
nameplate permanently attached to it. The following information, in 
addition to any applicable information required by the ASME Code, must 
be marked on the tank nameplate (parenthetical abbreviations may be 
used):
    (1) DOT-specification number DOT XXX (DOT XXX) where ``XXX'' is 
replaced with the applicable specification number. For cargo tanks 
having a variable specification plate, the DOT-specification number is 
replaced with the words ``See variable specification plate.''
    (2) Original test date, month and year (Orig. Test Date).
    (3) Tank MAWP in psig.
    (4) Cargo tank test pressure (Test P), in psig.
    (5) Cargo tank design temperature range (Design temp. range),-- 
[deg]F to -- [deg]F.
    (6) Nominal capacity (Water cap.), in gallons.
    (7) Maximum design density of lading (Max. lading density), in 
pounds per gallon.
    (8) Material specification number--shell (Shell matl, yyy***), where 
``yyy'' is replaced by the alloy designation and ``***'' by the alloy 
type.
    (9) Material specification number--heads (Head matl, yyy***), where 
``yyy'' is replaced by the alloy designation and ``***'' by the alloy 
type.

    Note: When the shell and heads materials are the same thickness, 
they may be combined, (Shell&head matl, yyy***).

    (10) Weld material (Weld matl.).
    (11) Minimum thickness--shell (Min. shell-thick), in inches. When 
minimum shell thicknesses are not the same for different areas, show 
(top --, side --, bottom --, in inches).
    (12) Minimum thickness--heads (Min. heads thick.), in inches.
    (13) Manufactured thickness--shell (Mfd. shell thick.), top --, side 
--, bottom --, in inches. (Required when additional thickness is 
provided for corrosion allowance.)

[[Page 175]]

    (14) Manufactured thickness--heads (Mfd. heads thick.), in inches. 
(Required when additional thickness is provided for corrosion 
allowance.)
    (15) Exposed surface area, in square feet.
    (c) Specification plate. Each cargo tank motor vehicle must have an 
additional corrosion resistant metal specification plate attached to it. 
The specification plate must contain the following information 
(parenthetical abbreviations may be used):
    (1) Cargo tank motor vehicle manufacturer (CTMV mfr.).
    (2) Cargo tank motor vehicle certification date (CTMV cert. date), 
if different from the cargo tank certification date.
    (3) Cargo tank manufacturer (CT mfr.).
    (4) Cargo tank date of manufacture (CT date of mfr.), month and 
year.
    (5) Maximum weight of lading (Max. Payload), in pounds.
    (6) Maximum loading rate in gallons per minute (Max. Load rate, 
GPM).
    (7) Maximum unloading rate in gallons per minute (Max. Unload rate).
    (8) Lining material (Lining), if applicable.
    (9) Heating system design pressure (Heating sys. press.), in psig, 
if applicable.
    (10) Heating system design temperature (Heating sys. temp.), in 
[deg]F, if applicable.
    (d) Multi-cargo tank motor vehicle. For a multi-cargo tank motor 
vehicle having all its cargo tanks not separated by any void, the 
information required by paragraphs (b) and (c) of this section may be 
combined on one specification plate. When separated by a void, each 
cargo tank must have an individual nameplate as required in paragraph 
(b) of this section, unless all cargo tanks are made by the same 
manufacturer with the same materials, manufactured thickness, minimum 
thickness and to the same specification. The cargo tank motor vehicle 
may have a combined nameplate and specification plate. When only one 
plate is used, the plate must be visible and not covered by insulation. 
The required information must be listed on the plate from front to rear 
in the order of the corresponding cargo tank location.
    (e) Variable specification cargo tank. Each variable specification 
cargo tank must have a corrosion resistant metal variable specification 
plate attached to it. The mounting of this variable specification plate 
must be such that only the plate identifying the applicable 
specification under which the tank is being operated is legible.
    (1) The following information must be included (parenthetical 
abbreviations are authorized):

    Specification DOT XXX (DOT XXX), where ``XXX'' is replaced with the 
applicable specification number.

 
            Equipment required                  Required rating \1\
 
Pressure relief devices:
    Pressure actuated type...............  ------------
    Frangible type.......................  ------------
    Lading discharge devices.............  ------------
    Top..................................  ------------
    Bottom...............................  ------------
    Pressure unloading fitting...........  ------------
Closures:
    Manhole..............................  ------------
    Fill openings........................  ------------
    Discharge openings...................  ------------
 
\1\ Required rating--to meet the applicable specification.

    (2) If no change of information in the specification plate is 
required, the letters ``NC'' must follow the rating required. If the 
cargo tank is not so equipped, the word ``None'' must be inserted.
    (3) Those parts to be changed or added must be stamped with the 
appropriate MC or DOT Specification markings.
    (4) The alterations that must be made in order for the tank to be 
modified from one specification to another must be clearly indicated on 
the manufacturer's certificate and on the variable specification plate.

[Amdt. 178-89, 54 FR 25027, June 12, 1989, as amended at 55 FR 37063, 
Sept. 7, 1990; Amdt. 178-99, 58 FR 51534, Oct. 1, 1993; Amdt. 178-104, 
59 FR 49135, Sept. 26, 1994; Amdt. 178-105, 59 FR 55176, Nov. 3, 1994; 
60 FR 17402, Apr. 5, 1995; Amdt. 178-118, 61 FR 51342, Oct. 1, 1996; 66 
FR 45389, Aug. 28, 2001; 68 FR 19284, Apr. 18, 2003; 68 FR 52371, Sept. 
3, 2003; 68 FR 75756, Dec. 31, 2003]

[[Page 176]]



Sec. 178.345-15  Certification.

    (a) At or before the time of delivery, the manufacturer of a cargo 
tank motor vehicle must provide certification documents to the owner of 
the cargo tank motor vehicle. The registration numbers of the 
manufacturer, the Design Certifying Engineer, and the Registered 
Inspector, as appropriate, must appear on the certificates (see subpart 
F, part 107 in subchapter A of this chapter).
    (b) The manufacturer of a cargo tank motor vehicle made to any of 
these specifications must provide:
    (1) For each design type, a certificate signed by a responsible 
official of the manufacturer and a Design Certifying Engineer certifying 
that the cargo tank motor vehicle design meets the applicable 
specification; and
    (2) For each ASME cargo tank, a cargo tank manufacturer's data 
report as required by Section VIII of the ASME Code (IBR, see Sec. 
171.7 of this subchapter). For each cargo tank motor vehicle, a 
certificate signed by a responsible official of the manufacturer and a 
Registered Inspector certifying that the cargo tank motor vehicle is 
constructed, tested and completed in conformance with the applicable 
specification.
    (c) The manufacturer of a variable specification cargo tank motor 
vehicle must provide:
    (1) For each design type, a certificate signed by a responsible 
official of the manufacturer and a Design Certifying Engineer certifying 
that the cargo tank motor vehicle design meets the applicable 
specifications; and
    (2) For each variable specification cargo tank motor vehicle, a 
certificate signed by a responsible official of the manufacturer and a 
Registered Inspector certifying that the cargo tank motor vehicle is 
constructed, tested and completed in conformance with the applicable 
specifications. The certificate must include all the information 
required and marked on the variable specification plate.
    (d) In the case of a cargo tank motor vehicle manufactured in two or 
more stages, each manufacturer who performs a manufacturing operation on 
the incomplete vehicle or portion thereof shall provide to the 
succeeding manufacturer, at or before the time of delivery, a 
certificate covering the particular operation performed by that 
manufacturer, including any certificates received from previous 
manufacturers, Registered Inspectors, and Design Certifying Engineers. 
Each certificate must indicate the portion of the complete cargo tank 
motor vehicle represented thereby, such as basic cargo tank fabrication, 
insulation, jacket, lining, or piping. The final manufacturer shall 
provide all applicable certificates to the owner.
    (e) Specification shortages. If a cargo tank is manufactured which 
does not meet all applicable specification requirements, thereby 
requiring subsequent manufacturing involving the installation of 
additional components, parts, appurtenances or accessories, the cargo 
tank manufacturer may affix the name plate and specification plate, as 
required by Sec. 178.345-14 (b) and (c), without the original date of 
certification stamped on the specification plate. The manufacturer shall 
state the specification requirements not complied with on the 
manufacturer's Certificate of Compliance. When the cargo tank is brought 
into full compliance with the applicable specification, the Registered 
Inspector shall stamp the date of compliance on the specification plate. 
The Registered Inspector shall issue a Certificate of Compliance stating 
details of the particular operations performed on the cargo tank, and 
the date and person (manufacturer, carrier, or repair organization) 
accomplishing the compliance.

[Amdt. 178-89, 55 FR 37063, Sept. 7, 1990, as amended by Amdt. 178-98, 
58 FR 33306, June 16, 1993; Amdt. 178-105, 59 FR 55176, Nov. 3, 1994; 
Amdt. 178-118, 61 FR 51342, Oct. 1, 1996; 68 FR 75756, Dec. 31, 2003]



Sec. 178.346  Specification DOT 406; cargo tank motor vehicle.



Sec. 178.346-1  General requirements.

    (a) Each Specification DOT 406 cargo tank motor vehicle must meet 
the general design and construction requirements in Sec. 178.345, in 
addition to the specific requirements contained in this section.

[[Page 177]]

    (b) MAWP: The MAWP of each cargo tank must be no lower than 2.65 
psig and no higher than 4 psig.
    (c) Vacuum loaded cargo tanks must not be constructed to this 
specification.
    (d) Each cargo tank must be ``constructed in accordance with Section 
VIII of the ASME Code'' (IBR, see Sec. 171.7 of this subchapter) except 
as modified herein:
    (1) The record-keeping requirements contained in the ASME Code 
Section VIII do not apply. Parts UG-90 through 94 in Section VIII do not 
apply. Inspection and certification must be made by an inspector 
registered in accordance with subpart F of part 107.
    (2) Loadings must be as prescribed in Sec. 178.345-3.
    (3) The knuckle radius of flanged heads must be at least three times 
the material thickness, and in no case less than 0.5 inch. Stuffed 
(inserted) heads may be attached to the shell by a fillet weld. The 
knuckle radius and dish radius versus diameter limitations of UG-32 do 
not apply. Shell sections of cargo tanks designed with a non-circular 
cross section need not be given a preliminary curvature, as prescribed 
in UG-79(b).
    (4) Marking, certification, data reports, and nameplates must be as 
prescribed in Sec. Sec. 178.345-14 and 178.345-15.
    (5) Manhole closure assemblies must conform to Sec. Sec. 178.345-5 
and 178.346-5.
    (6) Pressure relief devices must be as prescribed in Sec. 178.346-
3.
    (7) The hydrostatic or pneumatic test must be as prescribed in Sec. 
178.346-5.
    (8) The following paragraphs in parts UG and UW in Section VIII of 
the ASME Code do not apply: UG-11, UG-12, UG-22(g), UG-32(e), UG-34, UG-
35, UG-44, UG-76, UG-77, UG-80, UG-81, UG-96, UG-97, UW-13(b)(2), UW-
13.1(f) and the dimensional requirements found in Figure UW-13.1.
    (9) Single full fillet lap joints without plug welds may be used for 
arc or gas welded longitudinal seams without radiographic examination 
under the following conditions:
    (i) For a truck-mounted cargo tank, no more than two such joints may 
be used on the top half of the tank and no more than two joints may be 
used on the bottom half. They may not be located farther from the top 
and bottom centerline than 16 percent of the shell's circumference.
    (ii) For a self-supporting cargo tank, no more than two such joints 
may be used on the top of the tank. They may not be located farther from 
the top centerline than 12.5 percent of the shell's circumference.
    (iii) Compliance test. Two test specimens of the material to be used 
in the manufacture of a cargo tank must be tested to failure in tension. 
The test specimens must be of the same thicknesses and joint 
configuration as the cargo tank, and joined by the same welding 
procedures. The test specimens may represent all the tanks that are made 
of the same materials and welding procedures, have the same joint 
configuration, and are made in the same facility within 6 months after 
the tests are completed. Before welding, the fit-up of the joints on the 
test specimens must represent production conditions that would result in 
the least joint strength. Evidence of joint fit-up and test results must 
be retained at the manufacturers' facility.
    (iv) Weld joint efficiency. The lower value of stress at failure 
attained in the two tensile test specimens shall be used to compute the 
efficiency of the joint as follows: Determine the failure ratio by 
dividing the stress at failure by the mechanical properties of the 
adjacent metal; this value, when multiplied by 0.75, is the design weld 
joint efficiency.
    (10) The requirements of paragraph UW-9(d) in Section VIII of the 
ASME Code do not apply.

[Amdt. 178-89, 54 FR 25028, June 12, 1989, as amended at 55 FR 37063, 
Sept. 7, 1990; Amdt. 178-89, 56 FR 27877, June 17, 1991; Amdt. 178-105, 
59 FR 55176, Nov. 3, 1994; 65 FR 58631, Sept. 29, 2000; 66 FR 45387, 
Aug. 28, 2001; 68 FR 19285, Apr. 18, 2003; 68 FR 75756, Dec. 31, 2003]



Sec. 178.346-2  Material and thickness of material.

    The type and thickness of material for DOT 406 specification cargo 
tanks must conform to Sec. 178.345-2, but in no case may the thickness 
be less than that determined by the minimum thickness requirements in 
Sec. 178.320(a). The following Tables I and II identify

[[Page 178]]

the specified minimum thickness values to be employed in that 
determination.

 Table I--Specified Minimum Thickness of Heads (or Bulkheads and Baffles When Used as Tank Reinforcement) Using
   Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)--
                                 Expressed in Decimals of an Inch After Forming
----------------------------------------------------------------------------------------------------------------
                                                  Volume capacity in gallons per inch of length
                                --------------------------------------------------------------------------------
            Material                     14 or less               Over 14 to 23                 Over 23
                                --------------------------------------------------------------------------------
                                    MS    HSLA SS     AL       MS    HSLA SS     AL       MS    HSLA SS     AL
----------------------------------------------------------------------------------------------------------------
Thickness......................     .100     .100     .160     .115     .115     .173     .129     .129     .187
----------------------------------------------------------------------------------------------------------------


  Table II--Specified Minimum Thickness of Shell Using Mild Steel (MS),
 High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS),
  or Aluminum (AL)--Expressed in Decimals of an Inch After Forming \1\
------------------------------------------------------------------------
 Cargo tank motor vehicle rated capacity
                (gallons)                     MS      SS/HSLA      AL
------------------------------------------------------------------------
More than 0 to at least 4,500............     0.100      0.100     0.151
More than 4,500 to at least 8,000........     0.115      0.100     0.160
More than 8,000 to at least 14,000.......     0.129      0.129     0.173
More than 14,000.........................     0.143      0.143     0.187
------------------------------------------------------------------------
\1\ Maximum distance between bulkheads, baffles, or ring stiffeners
  shall not exceed 60 inches.


[Amdt. 178-89, 54 FR 25028, June 12, 1989, as amended at 55 FR 37064, 
Sept. 7, 1990; Amdt. 178-105, 59 FR 55176, Nov. 3, 1994; 68 FR 19285, 
Apr. 18, 2003]



Sec. 178.346-3  Pressure relief.

    (a) Each cargo tank must be equipped with a pressure relief system 
in accordance with Sec. 178.345-10 and this section.
    (b) Type and construction. In addition to the pressure relief 
devices required in Sec. 178.345-10:
    (1) Each cargo tank must be equipped with one or more vacuum relief 
devices;
    (2) When intended for use only for lading meeting the requirements 
of Sec. 173.33(c)(1)(iii) of this subchapter, the cargo tank may be 
equipped with a normal vent. Such vents must be set to open at not less 
than 1 psig and must be designed to prevent loss of lading through the 
device in case of vehicle upset; and
    (3) Notwithstanding the requirements in Sec. 178.345-10(b), after 
August 31, 1996, each pressure relief valve must be able to withstand a 
dynamic pressure surge reaching 30 psig above the design set pressure 
and sustained above the set pressure for at least 60 milliseconds with a 
total volume of liquid released not exceeding 1 L before the relief 
valve recloses to a leak-tight condition. This requirement must be met 
regardless of vehicle orientation. This capability must be demonstrated 
by testing. TTMA RP No. 81 (IBR, see Sec. 171.7 of this subchapter), 
cited at Sec. 178.345-10(b)(3)(i), is an acceptable test procedure.
    (c) Pressure settings of relief valves. (1) Notwithstanding the 
requirements in Sec. 178.345-10(d), the set pressure of each primary 
relief valve must be not less than 110 percent of the MAWP or 3.3 psig, 
whichever is greater, and not more than 138 percent of the MAWP. The 
valve must close at not less than the MAWP and remain closed at lower 
pressures.
    (2) Each vacuum relief device must be set to open at no more than 6 
ounces vacuum.
    (d) Venting capacities. (1) Notwithstanding the requirements in 
Sec. 178.345-10 (e) and (g), the primary pressure relief valve must 
have a venting capacity of at least 6,000 SCFH, rated at not greater 
than 125 percent of the tank test pressure and not greater than 3

[[Page 179]]

psig above the MAWP. The venting capacity required in Sec. 178.345-
10(e) may be rated at these same pressures.
    (2) Each vacuum relief system must have sufficient capacity to limit 
the vacuum to 1 psig.
    (3) If pressure loading or unloading devices are provided, the 
relief system must have adequate vapor and liquid capacity to limit the 
tank pressure to the cargo tank test pressure at maximum loading or 
unloading rate. The maximum loading and unloading rates must be included 
on the metal specification plate.

[Amdt. 178-89, 54 FR 25029, June 12, 1989, as amended at 55 FR 37064, 
Sept. 7, 1990; Amdt. 178-105, 59 FR 55176, Nov. 3, 1994. Redesignated by 
Amdt. 178-112, 61 FR 18934, Apr. 29, 1996; 66 FR 45389, Aug. 28, 2001; 
68 FR 75756, Dec. 31, 2003]



Sec. 178.346-4  Outlets.

    (a) All outlets on each tank must conform to Sec. 178.345-11 and 
this section.
    (b) External self-closing stop-valves are not authorized as an 
alternative to internal self-closing stop-valves on loading/unloading 
outlets.

[Amdt. 178-89, 54 FR 25029, June 12, 1989. Redesignated by Amdt. 178-
112, 61 FR 18934, Apr. 29, 1996]



Sec. 178.346-5  Pressure and leakage tests.

    (a) Each cargo tank must be tested in accordance with Sec. 178.345-
13 and this section.
    (b) Pressure test. Test pressure must be as follows:
    (1) Using the hydrostatic test method, the test pressure must be the 
greater of 5.0 psig or 1.5 times the cargo tank MAWP.
    (2) Using the pneumatic test method, the test pressure must be the 
greater of 5.0 psig or 1.5 times the cargo tank MAWP, and the inspection 
pressure must be the cargo tank MAWP.
    (c) Leakage test. A cargo tank used to transport a petroleum 
distillate fuel that is equipped with vapor recovery equipment may be 
leakage tested in accordance with 40 CFR 63.425(e). To satisfy the 
leakage test requirements of this paragraph, the test specified in 40 
CFR 63.425(e)(1) must be conducted using air. The hydrostatic test 
alternative permitted under Appendix A to 40 CFR Part 60 (``Method 27--
Determination of Vapor Tightness of Gasoline Delivery Tank Using 
Pressure-Vacuum Test'') may not be used to satisfy the leakage test 
requirements of this paragraph. A cargo tank tested in accordance with 
40 CFR 63.425(e) may be marked as specified in Sec. 180.415 of this 
subchapter.

[Amdt. 178-89, 54 FR 25029, June 12, 1989, as amended at 55 FR 37064, 
Sept. 7, 1990; Amdt. 178-105, 59 FR 55176, Nov. 3, 1994. Redesignated by 
Amdt. 178-112, 61 FR 18934, Apr. 29, 1996; 68 FR 19285, Apr. 18, 2003]



Sec. 178.347  Specification DOT 407; cargo tank motor vehicle.



Sec. 178.347-1  General requirements.

    (a) Each specification DOT 407 cargo tank motor vehicle must conform 
to the general design and construction requirements in Sec. 178.345 in 
addition to the specific requirements contained in this section.
    (b) Each tank must be of a circular cross-section and have an MAWP 
of at least 25 psig.
    (c) Any cargo tank motor vehicle built to this specification with a 
MAWP greater than 35 psig or any cargo tank motor vehicle built to this 
specification designed to be loaded by vacuum must be constructed and 
certified in accordance with Section VIII of the ASME Code (IBR, see 
Sec. 171.7 of this subchapter). The external design pressure for a 
cargo tank loaded by vacuum must be at least 15 psi.
    (d) Any cargo tank motor vehicle built to this specification with a 
MAWP of 35 psig or less or any cargo tank motor vehicle built to this 
specification designed to withstand full vacuum but not equipped to be 
loaded by vacuum must be constructed in accordance with Section VIII of 
the ASME Code.
    (1) The record-keeping requirements contained in Section VIII of the 
ASME Code do not apply. The inspection requirements of parts UG-90 
through 94 do not apply. Inspection and certification must be made by an 
inspector registered in accordance with subpart F of part 107.
    (2) Loadings must be as prescribed in Sec. 178.345-3.
    (3) The knuckle radius of flanged heads must be at least three times 
the

[[Page 180]]

material thickness, and in no case less than 0.5 inch. Stuffed 
(inserted) heads may be attached to the shell by a fillet weld. The 
knuckle radius and dish radius versus diameter limitations of UG-32 do 
not apply for cargo tank motor vehicles with a MAWP of 35 psig or less.
    (4) Marking, certification, data reports and nameplates must be as 
prescribed in Sec. Sec. 178.345-14 and 178.345-15.
    (5) Manhole closure assemblies must conform to Sec. 178.347-3.
    (6) Pressure relief devices must be as prescribed in Sec. 178.347-
4.
    (7) The hydrostatic or pneumatic test must be as prescribed in Sec. 
178.347-5.
    (8) The following paragraphs in parts UG and UW in Section VIII the 
ASME Code do not apply: UG-11, UG-12, UG-22(g), UG-32(e), UG-34, UG-35, 
UG-44, UG-76, UG-77, UG-80, UG-81, UG-96, UG-97, UW-12, UW-13(b)(2), UW-
13.1(f), and the dimensional requirements found in Figure UW-13.1.
    (9) UW-12 in Section VIII of the ASME Code does not apply to a weld 
seam in a bulkhead that has not been radiographically examined, under 
the following conditions:
    (i) The strength of the weld seam is assumed to be 0.85 of the 
strength of the bulkhead.
    (ii) The welded seam must be a full penetration butt weld.
    (iii) No more than one seam may be used per bulkhead.
    (iv) The welded seam must be completed before forming the dish 
radius and knuckle radius.
    (v) Compliance test: Two test specimens of materials representative 
of those to be used in the manufacture of a cargo tank bulkhead must be 
tested to failure in tension. The test specimen must be of the same 
thickness and joined by the same welding procedure. The test specimens 
may represent all the tanks that are made in the same facility within 6 
months after the tests are completed. Before welding, the fit-up of the 
joints on the test specimens must represent production conditions that 
would result in the least joint strength. Evidence of joint fit-up and 
test results must be retained at the manufacturer's facility for at 
least 5 years.
    (vi) Acceptance criteria: The ratio of the actual tensile stress at 
failure to the actual tensile strength of the adjacent material of all 
samples of a test lot must be greater than 0.85.

[Amdt. 178-89, 54 FR 25029, June 12, 1989, as amended at 55 FR 37064, 
Sept. 7, 1990; Amdt. 178-89, 56 FR 27877, June 17, 1991; 65 FR 58632, 
Sept. 29, 2000; 66 FR 45387, Aug. 28, 2001; 68 FR 19285, Apr. 18, 2003; 
68 FR 75756, Dec. 31, 2003; 76 FR 3388, Jan. 19, 2011; 76 FR 43532, July 
20, 2011]



Sec. 178.347-2  Material and thickness of material.

    (a) The type and thickness of material for DOT 407 specification 
cargo tanks must conform to Sec. 178.345-2, but in no case may the 
thickness be less than that determined by the minimum thickness 
requirements in Sec. 178.320(a). Tables I and II identify the specified 
minimum thickness values to be employed in that the determination:

 Table I--Specified Minimum Thickness of Heads (or Bulkheads and Baffles When Used as Tank Reinforcement) Using
   Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)--
                                 Expressed in Decimals of an Inch After Forming
----------------------------------------------------------------------------------------------------------------
                                              10 or    Over 10   Over 14   Over 18   Over 22   Over 26
    Volume capacity in gallons per inch       less      to 14     to 18     to 22     to 26     to 30    Over 30
----------------------------------------------------------------------------------------------------------------
Thickness (MS)............................     0.100     0.100     0.115     0.129     0.129     0.143     0.156
Thickness (HSLA)..........................     0.100     0.100     0.115     0.129     0.129     0.143     0.156
Thickness (SS)............................     0.100     0.100     0.115     0.129     0.129     0.143     0.156
Thickness (AL)............................     0.160     0.160     0.173     0.187     0.194     0.216     0.237
----------------------------------------------------------------------------------------------------------------


[[Page 181]]


   Table II--Specified Minimum Thickness of Shell Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA),
        Austenitic Stainless Steel (SS), or Aluminum (AL)--Expressed in Decimals of an Inch After Forming
----------------------------------------------------------------------------------------------------------------
                                              10 or    Over 10   Over 14   Over 18   Over 22   Over 26
    Volume capacity in gallons per inch       less      to 14     to 18     to 22     to 26     to 30    Over 30
----------------------------------------------------------------------------------------------------------------
Thickness (MS)............................     0.100     0.100     0.115     0.129     0.129     0.143     0.156
Thickness (HSLA)..........................     0.100     0.100     0.115     0.129     0.129     0.143     0.156
Thickness (SS)............................     0.100     0.100     0.115     0.129     0.129     0.143     0.156
Thickness (AL)............................     0.151     0.151     0.160     0.173     0.194     0.216     0.237
----------------------------------------------------------------------------------------------------------------

    (b) [Reserved]

[Amdt. 178-89, 54 FR 25030, June 12, 1989, as amended at 55 FR 37064, 
Sept. 7, 1990; Amdt. 178-104, 59 FR 49135, Sept. 26, 1994; 68 FR 19285, 
Apr. 18, 2003]



Sec. 178.347-3  Manhole assemblies.

    Each manhole assembly must conform to Sec. 178.345-5, except that 
each manhole assembly must be capable of withstanding internal fluid 
pressures of 40 psig or test pressure of the tank, whichever is greater.

[Amdt. 178-89, 54 FR 25030, June 12, 1989. Redesignated by Amdt. 178-
112, 61 FR 18934, Apr. 29, 1996]



Sec. 178.347-4  Pressure relief.

    (a) Each cargo tank must be equipped with a pressure and vacuum 
relief system in accordance with Sec. 178.345-10 and this section.
    (b) Type and construction. Vacuum relief devices are not required 
for cargo tank motor vehicles that are designed to be loaded by vacuum 
in accordance with Sec. 178.347-1(c) or built to withstand full vacuum 
in accordance with Sec. 178.347-1(d).
    (c) Pressure settings of relief valves. The setting of pressure 
relief valves must be in accordance with Sec. 178.345-10(d).
    (d) Venting capacities. (1) The vacuum relief system must limit the 
vacuum to less than 80 percent of the design vacuum capability of the 
cargo tank.
    (2) If pressure loading or unloading devices are provided, the 
relief system must have adequate vapor and liquid capacity to limit the 
tank pressure to the cargo tank test pressure at maximum loading or 
unloading rate. The maximum loading or unloading rate must be included 
on the metal specification plate.

[Amdt. 178-89, 54 FR 25030, June 12, 1989, as amended at 55 FR 37064, 
Sept. 7, 1990. Redesignated by Amdt. 178-112, 61 FR 18934, Apr. 29, 
1996; 76 FR 43532, July 20, 2011]



Sec. 178.347-5  Pressure and leakage test.

    (a) Each cargo tank must be tested in accordance with Sec. 178.345-
13 and this section.
    (b) Pressure test. Test pressure must be as follows:
    (1) Using the hydrostatic test method, the test pressure must be at 
least 40 psig or 1.5 times tank MAWP, whichever is greater.
    (2) Using the pneumatic test method, the test pressure must be 40 
psig or 1.5 times tank MAWP, whichever is greater, and the inspection 
pressure is tank MAWP.

[Amdt. 178-89, 54 FR 25030, June 12, 1989. Redesignated by Amdt. 178-
112, 61 FR 18934, Apr. 29, 1996]



Sec. 178.348  Specification DOT 412; cargo tank motor vehicle.



Sec. 178.348-1  General requirements.

    (a) Each specification DOT 412 cargo tank motor vehicle must conform 
to the general design and construction requirements in Sec. 178.345 in 
addition to the specific requirements of this section.
    (b) The MAWP of each cargo tank must be at least 5 psig.
    (c) The MAWP for each cargo tank designed to be loaded by vacuum 
must

[[Page 182]]

be at least 25 psig internal and 15 psig external.
    (d) Each cargo tank having a MAWP greater than 15 psig must be of 
circular cross-section.
    (e) Each cargo tank having a--
    (1) MAWP greater than 15 psig must be ``constructed and certified in 
conformance with Section VIII of the ASME Code'' (IBR, see Sec. 171.7 
of this subchapter); or
    (2) MAWP of 15 psig or less must be ``constructed in accordance with 
Section VIII of the ASME Code,'' except as modified herein:
    (i) The recordkeeping requirements contained in Section VIII of the 
ASME Code do not apply. Parts UG-90 through 94 in Section VIII do not 
apply. Inspection and certification must be made by an inspector 
registered in accordance with subpart F of part 107.
    (ii) Loadings must be as prescribed in Sec. 178.345-3.
    (iii) The knuckle radius of flanged heads must be at least three 
times the material thickness, and in no case less than 0.5 inch. Stuffed 
(inserted) heads may be attached to the shell by a fillet weld. The 
knuckle radius and dish radius versus diameter limitations of UG-32 do 
not apply for cargo tank motor vehicles with a MAWP of 15 psig or less. 
Shell sections of cargo tanks designed with a non-circular cross section 
need not be given a preliminary curvature, as prescribed in UG-79(b).
    (iv) Marking, certification, data reports, and nameplates must be as 
prescribed in Sec. Sec. 178.345-14 and 178.345-15.
    (v) Manhole closure assemblies must conform to Sec. Sec. 178.345-5.
    (vi) Pressure relief devices must be as prescribed in Sec. 178.348-
4.
    (vii) The hydrostatic or pneumatic test must be as prescribed in 
Sec. 178.348-5.
    (viii) The following paragraphs in parts UG and UW in Section VIII 
of the ASME Code do not apply: UG-11, UG-12, UG-22(g), UG-32(e), UG-34, 
UG-35, UG-44, UG-76, UG-77, UG-80, UG-81, UG-96, UG-97, UW-13(b)(2), UW-
13.1(f), and the dimensional requirements found in Figure UW-13.1.

[Amdt. 178-89, 54 FR 25031, June 12, 1989, as amended at 55 FR 37065, 
Sept. 7, 1990; Amdt. 178-89, 56 FR 27877, June 17, 1991; 65 FR 58632, 
Sept. 29, 2000; 68 FR 19285, Apr. 18, 2003; 68 fR 75756, Dec. 31, 2003]



Sec. 178.348-2  Material and thickness of material.

    (a) The type and thickness of material for DOT 412 specification 
cargo tanks must conform to Sec. 178.345-2, but in no case may the 
thickness be less than that determined by the minimum thickness 
requirements in Sec. 178.320(a). The following Tables I and II identify 
the ``Specified Minimum Thickness'' values to be employed in that 
determination.

[[Page 183]]



 Table I--Specified Minimum Thickness of Heads (or Bulkheads and Baffles When Used as Tank Reinforcement) Using Mild Steel (MS), High Strength Low Alloy
                     Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL)--Expressed in Decimals of an Inch After Forming
--------------------------------------------------------------------------------------------------------------------------------------------------------
   Volume capacity (gallons per inch)               10 or less                     Over 10 to 14               Over 14 to 18            18 and over
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
--------------------------------------------------------------------------------------------------------------------------------------------------------
Lading density at 60 [deg]F in pounds     10 lbs    Over    Over    Over  10 lbs    Over    Over    Over  10 lbs    Over    Over  10 lbs    Over    Over
 per gallon.............................     and   10 to   13 to  16 lbs     and   10 to   13 to  16 lbs     and   10 to   13 to     and   10 to   13 to
                                            less  13 lbs  16 lbs            less  13 lbs  16 lbs            less  13 lbs  16 lbs    less  13 lbs  16 lbs
Thickness (inch), steel.................    .100    .129    .157    .187    .129    .157    .187    .250    .157    .250    .250    .157    .250    .312
Thickness (inch), aluminum..............    .144    .187    .227    .270    .187    .227    .270    .360    .227    .360    .360    .227    .360    .450
--------------------------------------------------------------------------------------------------------------------------------------------------------


Table II--Specified Minimum Thickness of Shell Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum
                                                  (AL)--Expressed in Decimals of an Inch After Forming
--------------------------------------------------------------------------------------------------------------------------------------------------------
   Volume capacity in gallons per inch              10 or less                     Over 10 to 14               Over 14 to 18            18 and over
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
--------------------------------------------------------------------------------------------------------------------------------------------------------
Lading density at 60 [deg]F in pounds     10 lbs    Over    Over    Over  10 lbs    Over    Over    Over  10 lbs    Over    Over  10 lbs    Over    Over
 per gallon.............................     and   10 to   13 to  16 lbs     and   10 to   13 to  16 lbs     and   10 to   13 to     and   10 to   13 to
                                            less  13 lbs  16 lbs            less  13 lbs  16 lbs            less  13 lbs  16 lbs    less  13 lbs  16 lbs
Thickness (steel):
    Distances between heads (and
     bulkheads baffles and ring
     stiffeners when used as tank
     reinforcement):
        36 in. or less..................    .100    .129    .157    .187    .100    .129    .157    .187    .100    .129    .157    .129    .157    .187
        Over 36 in. to 54 inches........    .100    .129    .157    .187    .100    .129    .157    .187    .129    .157    .187    .157    .250    .250
        Over 54 in. to 60 inches........    .100    .129    .157    .187    .129    .157    .187    .250    .157    .250    .250    .187    .250    .312
Thickness (aluminum):
    Distances between heads (and
     bulkheads baffles and ring
     stiffeners when used as tank
     reinforcement):
        36 in. or less..................    .144    .187    .227    .270    .144    .187    .227    .270    .144    .187    .227    .187    .227    .270
        Over 36 in. to 54 inches........    .144    .187    .227    .270    .144    .187    .227    .270    .187    .227    .270    .157    .360    .360
        Over 54 in. to 60 inches........    .144    .187    .227    .270    .187    .227    .270    .360    .227    .360    .360    .270    .360    .450
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 184]]

    (b) [Reserved]

[Amdt. 178-89, 54 FR 25031, June 12, 1989; 54 FR 28750, July 7, 1989, as 
amended at 55 FR 37065, Sept. 7, 1990; 68 FR 19285, Apr. 18, 2003]



Sec. 178.348-3  Pumps, piping, hoses and connections.

    Each pump and all piping, hoses and connections on each cargo tank 
motor vehicle must conform to Sec. 178.345-9, except that the use of 
nonmetallic pipes, valves, or connections are authorized on DOT 412 
cargo tanks.

[Amdt. 178-89, 55 FR 37065, Sept. 7, 1990. Redesignated by Amdt. 178-
112, 61 FR 18934, Apr. 29, 1996]



Sec. 178.348-4  Pressure relief.

    (a) Each cargo tank must be equipped with a pressure and vacuum 
relief system in accordance with Sec. 178.345-10 and this section.
    (b) Type and construction. Vacuum relief devices are not required 
for cargo tanks designed to be loaded by vacuum or built to withstand 
full vacuum.
    (c) Pressure settings of relief valves. The setting of the pressure 
relief devices must be in accordance with Sec. 178.345-10(d), except as 
provided in paragraph (d)(3) of this section.
    (d) Venting capacities. (1) The vacuum relief system must limit the 
vacuum to less than 80 percent of the design vacuum capability of the 
cargo tank.
    (2) If pressure loading or unloading devices are provided, the 
pressure relief system must have adequate vapor and liquid capacity to 
limit tank pressure to the cargo tank test pressure at the maximum 
loading or unloading rate. The maximum loading and unloading rates must 
be included on the metal specification plate.
    (3) Cargo tanks used in dedicated service for materials classed as 
corrosive material, with no secondary hazard, may have a total venting 
capacity which is less than required by Sec. 178.345-10(e). The minimum 
total venting capacity for these cargo tanks must be determined in 
accordance with the following formula (use of approximate values given 
for the formula is acceptable):

                       Formula in Nonmetric Units

Q = 37,980,000 A0.82 (ZT)0.5 / 
(LC)(M0.5)

Where:

Q = The total required venting capacity, in cubic meters of air per hour 
          at standard conditions of 15.6 [deg]C and 1 atm (cubic feet of 
          air per hour at standard conditions of 60 [deg]F and 14.7 
          psia);
T = The absolute temperature of the vapor at the venting conditions--
          degrees Kelvin ([deg]C+273) [degrees Rankine ([deg]F+460)];
A = The exposed surface area of tank shell--square meters (square feet);
L = The latent heat of vaporization of the lading--calories per gram 
          (BTU/lb);
Z = The compressibility factor for the vapor (if this factor is unknown, 
          let Z equal 1.0);
M = The molecular weight of vapor;
C = A constant derived from (K), the ratio of specific heats of the 
          vapor. If (K) is unknown, let C = 315.

C = 520[K(2/(K+1))[(K+1)/(K-1)]]\0.5\

Where:

K = Cp / Cv
Cp = The specific heat at constant pressure, in -calories per 
          gram degree centigrade (BTU/lb [deg]F.); and
Cv = The specific heat at constant volume, in -calories per 
          gram degree centigrade (BTU/lb [deg]F.).

[Amdt. 178-89, 54 FR 25032, June 12, 1989, as amended at 55 FR 37065, 
Sept. 7, 1990; Amdt. 178-104, 59 FR 49135, Sept. 26, 1994. Redesignated 
by Amdt. 178-112, 61 FR 18934, Apr. 29, 1996; 72 FR 55696, Oct. 1, 2007; 
72 FR 59146, Oct. 18, 2007]



Sec. 178.348-5  Pressure and leakage test.

    (a) Each cargo tank must be tested in accordance with Sec. 178.345-
13 and this section.
    (b) Pressure test. Test pressure must be as follows:
    (1) Using the hydrostatic test method, the test pressure must be at 
least 1.5 times MAWP.
    (2) Using the pneumatic test method, the test pressure must be at 
least 1.5 times tank MAWP, and the inspection pressure is tank MAWP.

[Amdt. 178-89, 54 FR 25032, June 12, 1989. Redesignated by Amdt. 178-
112, 61 FR 18934, Apr. 29, 1996]

[[Page 185]]



   Subpart K_Specifications for Packagings for Class 7 (Radioactive) 
                                Materials



Sec. 178.350  Specification 7A; general packaging, Type A.

    (a) Each packaging must meet all applicable requirements of subpart 
B of part 173 of this subchapter and be designed and constructed so that 
it meets the requirements of Sec. Sec. 173.403, 173.410, 173.412, 
173.415 and 173.465 of this subchapter for Type A packaging.
    (b) Each Specification 7A packaging must be marked on the outside 
``USA DOT 7A Type A.''
    (c) Each Specification 7A packaging must comply with the marking 
requirements of Sec. 178.3. In paragraph 178.3(a)(2), the term 
``packaging manufacturer'' means the person certifying that the package 
meets all requirements of this section.

[Amdt. 178-109, 60 FR 50336, Sept. 28, 1995; 60 FR 54409, Oct. 23, 1995, 
as amended at 69 FR 3696, Jan. 26, 2004; 70 FR 56099, Sept. 23, 2005]



Sec. 178.356  Specification 20PF phenolic-foam insulated, metal overpack.



Sec. 178.356-1  General requirements.

    (a) Each overpack must meet all of the applicable requirements of 
Sec. 173.24 of this subchapter.
    (b) The maximum gross weight of the package, including the inner 
cylinder and its contents, must not exceed the following:
    (1) Specification 20PF-1--138 kg (300 pounds).
    (2) Specification 20PF-2--320 kg (700 pounds).
    (3) Specification 20PF-3--455 kg (1000 pounds).
    (c) The general configuration of the overpack must be a right 
cylinder, consisting of an insulated base section, a steel liner lid, 
and an insulated top section. The inner liner and outer shell must be at 
least 16-gauge and 18-gauge steel, respectively, with the intervening 
cavity filled with a molded-in-place, fire-resistant, phenolic-foam 
insulation interspersed with wooden members for bracing and support Wood 
pieces must be securely attached to both the liner and shell. No hole is 
permitted in the liner. Each joint between sections must be stepped a 
minimum of 5 cm (2 inches) and gaps between mating surfaces must not 
exceed 5 mm (0.2 inch). Gaps between foam surface of top section and 
liner lid must not exceed 1 cm (0.4 inch) or 5 cm (2 inches) where taper 
is required for mold stripping. For the specification 20PF-1, the top 
section may consist of a plug of foam insulation and a steel cover. The 
liner and shell closures must each be gasketed against moisture 
penetration. The liner must have a bolted flange closure. Shell closure 
must conform to paragraph (d) of this section.
    (d) Drums over 5 gallons capacity must be closed by means of 12-
gauge bolted ring with drop forged lugs, one of which is threaded, and 
having \3/8\ inch bolt and nut for drums not over 30 gallons capacity 
and \5/8\ inch bolt and nut for drums over 30 gallons capacity. Five 
gallon drums must be of lug type closure with cover having at least 16 
lugs.
    (e) Drawings in DOE CAPE-1662, Rev. 1 and Supplement 1 (IBR, see 
Sec. 171.7 of this subchapter), which include bills of material, are a 
part of this specification.

[Amdt. 178-35, 39 FR 45247, Dec. 31, 1974. Redesignated by Amdt. 178-97, 
55 FR 52716, Dec. 21, 1990; 65 FR 58632, Sept. 29, 2000; 66 FR 45386, 
45389, Aug. 28, 2001; 68 FR 75757, Dec. 31, 2003]



Sec. 178.356-2  Materials of construction and other requirements.

    (a) Phenolic foam insulation must be fire-resistant and fabricated 
in accordance with USDOE Material and Equipment Specification SP-9, Rev. 
1 and Supplement (IBR, see Sec. 171.7 of this subchapter), which is a 
part of this specification. (Note: Packagings manufactured under USAEC 
Specification SP-9 and Rev. 1 thereto are authorized for continued 
manufacture and use.) A 13.7 cm (5.4-inch) minimum thickness of foam 
must be provided over the entire liner except:
    (1) Where wood spacers replace the foam; or
    (2) At protrusions of liner or shell, such as flanges, baffles, 
etc., where minimum insulation thickness is 9 cm (3.5 inches); or
    (3) Where alternate top section (specification 20PF-1) is used. Foam 
must not interfere with proper seating of

[[Page 186]]

screws in inner liner flange assembly. Average density of insulation 
must be 0.13 g/cc (8 pounds per cubic foot (pcf)) minimum for bottom 
section and 0.16 g/cc (10 pcf) minimum for top section, except 0.1 g/cc 
(6.5 pcf) for the specification 20PF-1 top section.
    (b) Gaskets must be as follows:
    (1) Inner liner flange--Neoprene rubber of 30 to 60 type A durometer 
hardness or other equivalent gasket material which is compatible with 
the specific contents.
    (2) Outer shell--Synthetic rubber conforming to MIL-R-6855 
(available from the Naval Publications Forms Center, 5801 Tabor Avenue, 
Philadelphia, Pennsylvania 19120) class 2, grade 60.
    (3) Support and pressure pads for inner liner top and bottom must be 
sponge rubber or equivalent.
    (c) Alternate top section (specification 20PF-1 only). Average 
insulation density must be 0.16 g/cc (10 pcf minimum). Thickness of plug 
must be 11 cm (4.3 inches) minimum, except thickness may be reduced to 
10 cm (4 inches) to clear bolt heads. A flush mounted top lifting device 
must be securely fastened to a wood block encapsulated by the foam.
    (d) Vent holes 5 mm (0.2-inch) diameter must be drilled in the outer 
shell to provide pressure relief during the insulation foaming and in 
the event of a fire. These holes, which must be drilled in all areas of 
the shell that mate with the foam insulation, must be spaced in 
accordance with DOE CAPE-1662, Rev. 1 and Supplement 1 (IBR, see Sec. 
171.7 of this subchapter).
    (e) Welding must be by a fusion welding process in accordance with 
American Welding Society Codes B-3.0 and D-1.0 (IBR, see Sec. 171.7 of 
this subchapter). Body seams and joints for the liner or shell must be 
continuous welds.
    (f) Waterproofing. Each screw hole in the outer shell must be sealed 
with appropriate resin-type sealing material, or equivalent, during 
installation of the screw. All exposed foam surfaces, including any vent 
hole, must be sealed with waterproofing material as prescribed in USDOE 
Material and Equipment Specification SP-9, Rev. 1 and Supplement, or 
equivalent.

[Amdt. 178-35, 39 FR 45247, Dec. 31, 1974, as amended by Amdt. 178-56, 
44 FR 49458, Aug. 23, 1979. Redesignated by Amdt. 178-97, 55 FR 52716, 
Dec. 21, 1990; 66 FR 45387, Aug. 28, 2001; 68 FR 75757, Dec. 31, 2003]



Sec. 178.356-3  Tests.

    (a) Leakage test--Each inner liner assembly must be tested for 
leakage prior to installation. Seam welds of the liner must be covered 
for a distance of at least 15 cm (6 inches) on either side of the seam 
with soapsuds, heavy oil, or equivalent material, and interior air 
pressure applied to at least 776 mm Hg (15 p.s.i.g.) above atmospheric 
pressure must be held for at least 30 seconds. Liners failing to pass 
this test may not be used until repairs are made, and retests 
successfully passed.
    (b) [Reserved]

[Amdt. 178-35, 39 FR 45247, Dec. 31, 1974. Redesignated by Amdt. 178-97, 
55 FR 52716, Dec. 21, 1990; 66 FR 45387, Aug. 28, 2001; 67 FR 61016, 
Sept. 27, 2002]



Sec. 178.356-4  Required markings.

    (a) Marking must be as prescribed in Sec. 178.3.
    (b) Marking on the outside of each overpack must be as follows:
    (1) ``USA-DOT-20PF-1'' or ``-2,'' as appropriate, and if the entire 
liner is made of stainless steel, additional marking such as ``3041-SS'' 
to indicate the type of stainless steel used.
    (2) ``TARE WT: xxx lbs.'' where xxx is the tare weight of the 
assembled overpack without the inner container.
    (3) Year of manufacture.

[Amdt. 178-35, 39 FR 45247, Dec. 31, 1974. Redesignated by Amdt. 178-97, 
55 FR 52716, Dec. 21, 1990, as amended at 63 FR 37462, July 10, 1998]



Sec. 178.356-5  Typical assembly detail.

    (a) Specifications 20PF-1.

[[Page 187]]

[GRAPHIC] [TIFF OMITTED] TC02MR91.077

    (b) Specification 20PF-2.

[[Page 188]]

[GRAPHIC] [TIFF OMITTED] TC02MR91.078

    (c) Specification 20PF-3.

[[Page 189]]

[GRAPHIC] [TIFF OMITTED] TC02MR91.079


[Amdt. 178-35, 39 FR 45247, Dec. 31, 1974. Redesignated by Amdt. 178-97, 
55 FR 52716, Dec. 21, 1990]

[[Page 190]]



Sec. 178.358  Specification 21PF fire and shock resistant, phenolic-
foam insulated, metal overpack.



Sec. 178.358-1  General requirements.

    (a) Each overpack must meet all of the applicable requirements of 
Sec. Sec. 173.24, 173.411, and 173.412 of this subchapter.
    (1) Specification 21PF-1 overpacks includes the series of 21PF-1, 
21PF-1A, and 21PF-1B models. Details of the three models are included in 
DOE CAPE-1662, Rev. 1 and Supplement 1 (IBR, see Sec. 171.7 of this 
subchapter).
    (2) Drawings in CAPE-1662, Rev. 1 and Supplement 1, that include 
bills of materials, and KSS-471 (IBR, see Sec. 171.7 of this 
subchapter), are a part of this specification.
    (b) Each overpack is authorized for use in applications where the 
maximum gross weight of the package, including the inner container and 
contents does not exceed 3725 kg (8200 pounds), (horizontally-loaded 
specification 21 PF-1 unit), or 3900 kg (8600 pounds), (end-loaded 
specification 21 PF-2 unit).
    (c) The general configuration of the overpack must be a right 
cylinder, consisting of a steel inner liner (at least 16-gauge) and 
steel outer shell (at least 14-gauge) with the intervening cavity filled 
with a molded-in-place, fire-resistant, phenolic foam insulation and 
interspersed wooden members for bracing and support. Two specific 
configurations are authorized; a horizontal loading unit (specification 
21PF-1) consisting of insulated base and top sections jointed in a 
longitudinal peripheral closure joint; or an end-loading unit 
(specification 21PF-2), consisting of an insulated main section, a steel 
plate liner lid, and an insulated end cap. For either type each joint 
between sections must be stepped at least 1.8 cm (0.75-inch) and gaps 
between mating surfaces may not exceed 5 mm (0.2-inch). Bolted closures, 
which must each be gasketed against moisture penetration, must be in 
accordance with CAPE-1662. Each bolt must be equipped with a locking 
device to prevent loosening from vibration. Outer steel bracing and 
support framework must be attached to the shell to facilitate normal 
handling.
    (d) Specification 21PF-1 overpacks in use or under construction 
before April 1, 1989, must be modified to Specification 21PF-1A before 
April 1, 1991. All new construction to Specification 21PF-1 beginning 
after March 31, 1989, must meet Specification 21PF-1B. Use of unmodified 
21PF-1 overpacks after March 31, 1991, is prohibited.

[Amdt. 178-35, 39 FR 45250, Dec. 31, 1974; 40 FR 2435, Jan. 13, 1975, as 
amended by Amdt. 178-90, 53 FR 36551, Sept. 20, 1988. Redesigntated by 
Amdt. 178-97, 55 FR 52716, Dec. 21, 1990; 66 FR 45387, Aug. 28, 2001; 68 
FR 75757, Dec. 31, 2003]



Sec. 178.358-2  Materials of construction and other requirements.

    (a) Phenolic foam insulation must be fire resistant and fabricated 
in accordance with USDOE Material and Equipment Specification SP-9, Rev. 
1 and Supplement (IBR, see Sec. 171.7 of this subchapter), which is a 
part of this specification. (Note: Packagings manufactured under USAEC 
Specification SP-9, and Rev. 1 thereto are authorized for continued 
manufacture and use.) A 14 cm (5.5-inch) minimum thickness of foam must 
be provided over the entire liner except where:
    (1) Wood spacers replace the foam material; or
    (2) At protrusions of liner or shell, such as flanges, baffles, 
etc., where the minimum thickness of foam, wood, or a combination of 
these is 10 cm (4 inches).
    (3) Solid wood or laminated wood solidly glued may be used to 
replace the foam between liner and shell (i.e., in ends of overpack). In 
this case, minimum wood thickness is 10 cm (4 inches). Average density 
of insulation must be 0.1g/cc (6.75 pounds per cubic foot (pcf)) 
minimum, except that 0.13 g/cc (8 pcf) is required in the removable end 
cap of the specification 21PF-2, which must have a minimum foam 
thickness of 12.7 cm (5 inches).
    (b) Gaskets for inner liner, outer shell, or where otherwise 
specified in DOE CAPE-1662, Rev. 1 (IBR, see Sec. 171.7 of this 
subchapter), must be as specified in DOE CAPE-1662, Rev. 1.
    (c) Support and pressure pads for the inner liner must be of 
neoprene, sponge rubber, or equivalent.

[[Page 191]]

    (d) Fire-retardant (intumescent) paint must be applied to any wood 
blocking which is located at any joint in the shell.
    (e) Vent holes 5 mm (0.2-inch) diameter must be drilled in the outer 
shell to provide pressure relief during the insulation foaming and in 
the event of a fire. These holes, which must be drilled in all areas of 
the shell which made with the foam insulation, must be spaced in 
accordance with CAPE-1662.
    (f) Welding must be by a fusion process in accordance with the 
American Welding Society Codes B-3.0 and D-1.0 (IBR, see Sec. 171.7 of 
this subchapter). Body seams and joints for the liner and shell must be 
continuous welds.
    (g) Waterproofing. Each screw hole in the outer shell must be sealed 
with appropriate resin-type sealing material, or equivalent, during 
installation of the screw. All exposed foam surfaces, including any vent 
hole, must be sealed with either:
    (1) Waterproofing material as prescribed in USDOE Material and 
Equipment Specification SP-9, Rev. 1 and Supplement, or
    (2) As specified in CAPE-1662, Revision 1.

[Amdt. 178-35, 39 FR 45250, Dec. 31, 1974, as amended by Amdt. 178-56, 
44 FR 49459, Aug. 23, 1979; Amdt. 178-90, 53 FR 36551, Sept. 20, 1988. 
Redesigntated by Amdt. 178-97, 55 FR 52716, Dec. 21, 1990; 66 FR 45387, 
Aug. 28, 2001; 68 FR 75757, Dec. 31, 2003]



Sec. 178.358-3  Modification of Specification 21PF-1 overpacks.

    (a) Each Specification 21PF-1 overpack for which construction began 
or was completed before April 1, 1989, in conformance with drawing E-S-
31536-J, Rev. 1 of DOE CAPE-1662 (IBR, see Sec. 171.7 of this 
subchapter), must be modified in conformance with drawing S1E-31536-J1-D 
of DOE CAPE-1662, Rev. 1, Supplement 1, before April 1, 1991.
    (b) Each such existing Specification 21PF-1 overpack must be dried 
and weighed in accordance with the following procedures:
    (1) Drill out or otherwise clean the plug material from the vent 
holes originally provided for foam expansion. See drawing S1E-31536-J1-D 
of CAPE-1662, Revision 1, Supplement 1, for locations.
    (2) Weigh each packaging element (top and bottom halves) separately 
to an accuracy of 2.3 kg (5 
pounds) and record the weights. If this measured weight exceeds the 
initially measured weight at the time of fabrication by 11.3 kg (25 
pounds) (indicating a significant retained water content), the packaging 
element must be dried.
    (3) Place overpack element in drying oven; maintain temperature 
between 87.8-98.9 [deg]C (190[deg] and 210 [deg]F) for a minimum of 72 
hours. The oven should have a provision for air exchange or other means 
of removing moisture driven from the foam structure.
    (4) Drying may be discontinued after 72 hours if the weight of the 
packaging element does not exceed the initially measured tare weight of 
that element at the time of fabrication by more than 11.3 kg (25 
pounds). If the weight of the packaging element exceeds the initial 
fabricated weight (indicating a significant remaining water content) by 
more than 11.3 kg (25 pounds), drying must be continued until the weight 
differential is not higher than 11.3 kg (25 pounds), or until the rate 
of weight loss is less than 1.1 kg (2.5 pounds) per day.
    (5) As an alternate moisture measurement, a calibrated moisture 
meter reading for 20 percent maximum water content may be used to 
indicate an end point in the drying cycle, which is detailed in report 
``Renovation of DOT Specification 21PF-1 Protective Shipping Packages,'' 
Report No. K-2057, Revision 1, November 21, 1986, available from the 
USDOE and part of USDOE Report No. KSS-471 (IBR, see Sec. 171.7 of this 
subchapter).
    (6) Following drying, each overpack element (top and bottom halves) 
must be weighed and the weight in both pounds and kilograms must be 
engraved on the identification plate required by Sec. 178.358-5(c).
    (c) After modification as provided for herein, each Specification 
21PF-1 overpack must be marked ``USA-DOT-21PF-

[[Page 192]]

1A''. See the marking requirements of Sec. 178.358-5.

[Amdt. 178-90, 53 FR 36551, Sept. 20, 1988. Redesigntated by Amdt. 178-
97, 55 FR 52716, Dec. 21, 1990; Amdt. 178-110, 60 FR 49111, Sept. 21, 
1995; 63 FR 37462, July 10, 1998; 66 FR 45389, Aug. 28, 2001; 68 FR 
75757, Dec. 31, 2003]



Sec. 178.358-4  Construction of Specification 21PF-1B overpacks.

    (a) Each Specification 21PF-1 overpack for which construction began 
after March 31, 1989, must meet the requirements of Specification 21PF-
1B, in conformance with drawings E-S-31536-J-P, and S1E-31536-J2-B of 
DOE CAPE-1662, Rev. 1, Supplement 1 (IBR, see Sec. 171.7 of this 
subchapter).
    (b) With the exception of the closure nuts and bolts, all metal 
parts of the Specification 21PF-1B must be of stainless steel as shown 
on the drawings referred to in paragraph (a) of this section.

[Amdt. 178-90, 53 FR 36551, Sept. 20, 1988. Redesigntated by Amdt. 178-
97, 55 FR 52716, Dec. 21, 1990; 68 FR 75757, Dec. 31, 2003]



Sec. 178.358-5  Required markings.

    (a) Markings must be as prescribed in Sec. 178.3.
    (b) Specification marking on the outside of each overpack must be as 
follows: ``USA-DOT-21PF-1'', ``1A'', ``1B'', or ``2'', as appropriate.
    (1) For Specifications 21PF-1 and 21PF-2 only, if the inner shell is 
constructed of stainless steel, additional marking such as ``304L-SS'' 
are to be marked on the outside of the overpack to indicate the type of 
stainless steel used.
    (2) For Specification 21PF-1 and 21PF-2 only, ``TARE WT: * * * lbs. 
(* * * kg)'' where * * * is the tare weight in pounds and kilograms, 
respectively, of the assembled overpack without the inner product 
container.
    (3) For Specification 21PF-1A and 21PF-1B only: ``TARE WT. of Cover: 
* * * lbs (* * * kg) TARE WT. of BOTTOM: * * * lbs (* * * kg)'' where * 
* * is the tare weight in pounds and kilograms, respectively, of the 
separate halves of the overpack without the inner product container. For 
Specification 21PF-1A overpacks, the previous tare weight must be 
changed to reflect the modified tare weight value or must be covered or 
removed.
    (4) Year of manufacture followed by the year of modification, if 
applicable.
    (5) The name or symbol of maker or party certifying compliance with 
specification requirements. A symbol, if used, must be registered with 
the Associate Administrator.
    (c) For Specification 21PF-1A and -1B only, the markings required by 
this section must be affixed to each overpack by inscription upon a 
metal identification plate 11 inches wide x 15 inches long (28 cm x 38 
cm), fabricated of 16 to 20 gauge stainless steel sheet, ASTM A-240/A 
240M (IBR, see Sec. 171.7 of this subchapter), Type 304L.

[Amdt. 178-90, 53 FR 36552, Sept. 20, 1988. Redesigntated by Amdt. 178-
97, 55 FR 52716, Dec. 21, 1990, and amended at Amdt. 178-97, 56 FR 
66287, Dec. 20, 1991; 63 FR 37462, July 10, 1998; 66 FR 45386, Aug. 28, 
2001; 67 FR 51660, Aug. 8, 2002; 68 FR 75748, Dec. 31, 2003; 69 FR 
54046, Sept. 7, 2004]



Sec. 178.358-6  Typical assembly detail.

    (a) Specification 21PF-1 (horizontal loading overpack).

[[Page 193]]

[GRAPHIC] [TIFF OMITTED] TC02MR91.080

    (b) Specification 21PF-1A and 21PF-1B (horizontal loading overpack).

[[Page 194]]

[GRAPHIC] [TIFF OMITTED] TC02MR91.081

    (c) Specification 21PF-2 (end loading overpack).

[[Page 195]]

[GRAPHIC] [TIFF OMITTED] TC02MR91.082


[Amdt. 178-90, 53 FR 36552, Sept. 20, 1988. Redesignated by Amdt. 178-
97, 55 FR 52716, Dec. 21, 1990]

[[Page 196]]



Sec. 178.360  Specification 2R; inside containment vessel.



Sec. 178.360-1  General requirements.

    (a) Each vessel must be made of stainless steel, malleable iron, or 
brass, or other material having equivalent physical strength and fire 
resistance.
    (b) Each vessel must meet all of the applicable requirements of 
Sec. 173.24 (c) and (d) of this subchapter. Letters and numerals at 
least 6 mm (\1/4\-inch) in height are authorized for the marking of a 
vessel not exceeding 5 cm (2 inches) inside diameter.

[Amdt. 178-35, 39 FR 45245, Dec. 31, 1974. Redesignated by Amdt. 178-97, 
55 FR 52716, Dec. 21, 1990; 66 FR 45387, Aug. 28, 2001]



Sec. 178.360-2  Manufacture.

    The ends of the vessel must be fitted with screw-type closures or 
flanges (see Sec. 178.360-4), except that one or both ends of the 
vessel may be permanently closed by a welded or brazed plate. Welded or 
brazed side seams are authorized.

[Amdt. 178-35, 39 FR 45245, Dec. 31, 1974. Redesignated by Amdt. 178-97, 
55 FR 52716, Dec. 21, 1990, as amended at 63 FR 37462, July 10, 1998]



Sec. 178.360-3  Dimensions.

    (a) The inside diameter of the vessel may not exceed 30 cm (12 
inches) exclusive of flanges for handling or fastening devices and must 
have wall thickness and length in accordance with the following:

----------------------------------------------------------------------------------------------------------------
  Inside diameter    Threaded closure                                                           Length maximum
      maximum      --------------------                                                      -------------------
-------------------                            Wall thickness minimum--Flanged closure
 Inches      Cm      Inches      Mm                                                            Inches      Cm
----------------------------------------------------------------------------------------------------------------
       2         5    \3/32\       2.5  Not less than that prescribed for schedule 40 pipe..        16        41
       6        15     \1/8\       3.2  ....................................................        72       183
      12        30     \1/4\       6.5  ....................................................        72       183
----------------------------------------------------------------------------------------------------------------

    (b) [Reserved]

[Amdt. 178-35, 39 FR 45245, Dec. 31, 1974. Redesignated by Amdt. 178-97, 
55 FR 52716, Dec. 21, 1990; 66 FR 45387, Aug. 28, 2001]



Sec. 178.360-4  Closure devices.

    (a) Each closure device must be as follows:
    (1) Screw-type cap or plug; number of threads per inch must not be 
less than United States standard pipe threads and must have sufficient 
length of thread to engage at least 5 threads when securely tightened. 
Pipe threads must be luted with an appropriate non-hardening compound 
which must be capable of withstanding up to 149 [deg]C (300 [deg]F) 
without loss of efficiency. Tightening torque must be adequate to 
maintain leak tightness with the specific luting compound.
    (2) An opening may be closed by a securely bolted flange and leak-
tight gasket. Each flange must be welded or brazed to the body of the 2R 
vessel per (ANSI) Standard B16.5 or (AWWA) Standard C207-55, section 10 
(IBR, see Sec. 171.7 of this subchapter). A torque wrench must be used 
in securing the flange with a corresponding torque of no more than twice 
the force necessary to seal the selected gasket. Gasket material must be 
capable of withstanding up to 149 [deg]C (300 [deg]F) without loss of 
efficiency. The flange, whether of ferrous or nonferrous metal, must be 
constructed from the same metal as the vessel and must meet the 
dimensional and fabrication specifications for welded construction as 
follows:
    (i) Pipe flanges described in Tables 13, 14, 16, 17, 19, 20, 22, 23, 
25 and 26 of ANSI B16.5 (IBR, see Sec. 171.7 of this subchapter).
    (ii) For nominal pipe sizes, 6, 8, 10, and 12 inches, AWWA Standard 
C207-55, Table 1, class B, may be used in place of the tables prescribed 
by paragraph (a)(2)(i) of this section.

[[Page 197]]

    (iii) Sizes under 6 inches, nominal pipe size, the following table 
with the same configuration as illustrated in AWWA C207-55, Table 1, 
class B, may be used in place of paragraph (a)(2)(i) of this section.

----------------------------------------------------------------------------------------------------------------
  Nominal pipe size        Flange O.D.                    Bolt circle      Diameter of bolts   Flange thickness
-------------------------------------------  Number        diameter      ---------------------------------------
                                            of bolts --------------------
  Inches       Cm       Inches       Cm                Inches      Cm      Inches      Cm      Inches      Cm
----------------------------------------------------------------------------------------------------------------
       2          5          6         15          4    4\3/4\      11.8     \1/2\       1.2     \5/8\       1.6
  2\1/2\        6.2          7       17.5          4    5\1/2\      13.8     \1/2\  ........     \5/8\  ........
       3        7.5     7\1/2\       18.8          4         6        15     \1/2\  ........     \5/8\  ........
  3\1/2\        8.8     8\1/2\       21.3          8         7      17.5     \1/2\  ........     \5/8\  ........
       4         10          9       22.5          8    7\1/2\      18.8     \1/2\  ........     \5/8\  ........
       5       12.6         10       25.4          8    8\1/2\      21.3     \1/2\  ........     \5/8\  ........
----------------------------------------------------------------------------------------------------------------

    (iv) Cast iron flanges prohibited.
    (b) [Reserved]

[Amdt. 178-35, 39 FR 45245, Dec. 31, 1974; 40 FR 2435, Jan. 13, 1975, as 
amended at 40 FR 44327, Sept. 26, 1975. Redesignated by Amdt. 178-97, 56 
FR 66284, Dec. 20, 1991; 68 FR 75757, Dec. 31, 2003]



       Subpart L_Non-bulk Performance-Oriented Packaging Standards

    Source: Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, unless otherwise 
noted.



Sec. 178.500  Purpose, scope and definitions.

    (a) This subpart prescribes certain requirements for non-bulk 
packagings for hazardous materials. Standards for these packagings are 
based on the UN Recommendations.
    (b) Terms used in this subpart are defined in Sec. 171.8 of this 
subchapter.



Sec. 178.502  Identification codes for packagings.

    (a) Identification codes for designating kinds of packagings consist 
of the following:
    (1) A numeral indicating the kind of packaging, as follows:
    (i) ``1'' means a drum.
    (ii) ``2'' means a wooden barrel.
    (iii) ``3'' means a jerrican.
    (iv) ``4'' means a box.
    (v) ``5'' means a bag.
    (vi) ``6'' means a composite packaging.
    (vii) ``7'' means a pressure receptacle.
    (2) A capital letter indicating the material of construction, as 
follows:
    (i) ``A'' means steel (all types and surface treatments).
    (ii) ``B'' means aluminum.
    (iii) ``C'' means natural wood.
    (iv) ``D'' means plywood.
    (v) ``F'' means reconstituted wood.
    (vi) ``G'' means fiberboard.
    (vii) ``H'' means plastic.
    (viii) ``L'' means textile.
    (ix) ``M'' means paper, multi-wall.
    (x) ``N'' means metal (other than steel or aluminum).
    (xi) ``P'' means glass, porcelain or stoneware.
    (3) A numeral indicating the category of packaging within the kind 
to which the packaging belongs. For example, for steel drums (``1A''), 
``1'' indicates a non-removable head drum (i.e., ``1A1'') and ``2'' 
indicates a removable head drum (i.e., ``1A2'').
    (b) For composite packagings, two capital letters are used in 
sequence in the second position of the code, the first indicating the 
material of the inner receptacle and the second, that of the outer 
packaging. For example, a plastic receptacle in a steel drum is 
designated ``6HA1''.
    (c) For combination packagings, only the code number for the outer 
packaging is used.
    (d) Identification codes are set forth in the standards for 
packagings in Sec. Sec. 178.504 through 178.523 of this subpart.

    Note to Sec. 178.502: Plastics materials include other polymeric 
materials such as rubber.

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-106, 
59 FR 67519, Dec. 29, 1994; 74 FR 2269, Jan. 14, 2009]



Sec. 178.503  Marking of packagings.

    (a) A manufacturer must mark every packaging that is represented as 
manufactured to meet a UN standard with the marks specified in this 
section. The

[[Page 198]]

markings must be durable, legible and placed in a location and of such a 
size relative to the packaging as to be readily visible, as specified in 
Sec. 178.3(a). Except as otherwise provided in this section, every 
reusable packaging liable to undergo a reconditioning process which 
might obliterate the packaging marks must bear the marks specified in 
paragraphs (a)(1) through (a)(6) and (a)(9) of this section in a 
permanent form (e.g. embossed) able to withstand the reconditioning 
process. A marking may be applied in a single line or in multiple lines 
provided the correct sequence is used. As illustrated by the examples in 
paragraph (e) of this section, the following information must be 
presented in the correct sequence. Slash marks should be used to 
separate this information. A packaging conforming to a UN standard must 
be marked as follows:
    (1) Except as provided in paragraph (e)(1)(ii) of this section, the 
United Nations symbol as illustrated in paragraph (e)(1)(i) of this 
section (for embossed metal receptacles, the letters ``UN'') may be 
applied in place of the symbol;;
    (2) A packaging identification code designating the type of 
packaging, the material of construction and, when appropriate, the 
category of packaging under Sec. Sec. 178.504 through 178.523 of this 
subpart within the type to which the packaging belongs. The letter ``V'' 
must follow the packaging identification code on packagings tested in 
accordance with Sec. 178.601(g)(2); for example, ``4GV''. The letter 
``W'' must follow the packaging identification code on packagings when 
required by an approval under the provisions of Sec. 178.601(h) of this 
part;
    (3) A letter identifying the performance standard under which the 
packaging design type has been successfully tested, as follows:
    (i) X--for packagings meeting Packing Group I, II and III tests;
    (ii) Y--for packagings meeting Packing Group II and III tests; or
    (iii) Z--for packagings only meeting Packing Group III tests;
    (4) A designation of the specific gravity or mass for which the 
packaging design type has been tested, as follows:
    (i) For packagings without inner packagings intended to contain 
liquids, the designation shall be the specific gravity rounded down to 
the first decimal but may be omitted when the specific gravity does not 
exceed 1.2; and
    (ii) For packagings intended to contain solids or inner packagings, 
the designation shall be the maximum gross mass in kilograms;
    (5)(i) For single and composite packagings intended to contain 
liquids, the test pressure in kilopascals rounded down to the nearest 10 
kPa of the hydrostatic pressure test that the packaging design type has 
successfully passed;
    (ii) For packagings intended to contain solids or inner packagings, 
the letter ``S'';
    (6) The last two digits of the year of manufacture. Packagings of 
types 1H and 3H shall also be marked with the month of manufacture in 
any appropriate manner; this may be marked on the packaging in a 
different place from the remainder of the markings;
    (7) The state authorizing allocation of the mark. The letters `USA' 
indicate that the packaging is manufactured and marked in the United 
States in compliance with the provisions of this subchapter;
    (8) The name and address or symbol of the manufacturer or the 
approval agency certifying compliance with subpart L and subpart M of 
this part. Symbols, if used, must be registered with the Associate 
Administrator;
    (9) For metal or plastic drums or jerricans intended for reuse or 
reconditioning as single packagings or the outer packagings of a 
composite packaging, the thickness of the packaging material, expressed 
in mm (rounded to the nearest 0.1 mm), as follows:
    (i) Metal drums or jerricans must be marked with the nominal 
thickness of the metal used in the body. The marked nominal thickness 
must not exceed the minimum thickness of the steel used by more than the 
thickness tolerance stated in ISO 3574 (IBR, see Sec. 171.7 of this 
subchapter). (See appendix C of this part.) The unit of measure is not 
required to be marked. When the nominal thickness of either head of a 
metal drum is thinner than that of the body, the nominal thickness of 
the top

[[Page 199]]

head, body, and bottom head must be marked (e.g., ``1.0-1.2-1.0'' or 
``0.9-1.0-1.0'').
    (ii) Plastic drums or jerricans must be marked with the minimum 
thickness of the packaging material. Minimum thicknesses of plastic must 
be as determined in accordance with Sec. 173.28(b)(4). The unit of 
measure is not required to be marked;
    (10) In addition to the markings prescribed in paragraphs (a)(1) 
through (a)(9) of this section, every new metal drum having a capacity 
greater than 100 L must bear the marks described in paragraphs (a)(1) 
through (a)(6), and (a)(9)(i) of this section, in a permanent form, on 
the bottom. The markings on the top head or side of these packagings 
need not be permanent, and need not include the thickness mark described 
in paragraph (a)(9) of this section. This marking indicates a drum's 
characteristics at the time it was manufactured, and the information in 
paragraphs (a)(1) through (a)(6) of this section that is marked on the 
top head or side must be the same as the information in paragraphs 
(a)(1) through (a)(6) of this section permanently marked by the original 
manufacturer on the bottom of the drum; and
    (11) Rated capacity of the packaging expressed in liters may be 
marked.
    (b) For a packaging with a removable head, the markings may not be 
applied only to the removable head.
    (c) Marking of reconditioned packagings. (1) If a packaging is 
reconditioned, it shall be marked by the reconditioner near the marks 
required in paragraphs (a)(1) through (6) of this section with the 
following additional information:
    (i) The name of the country in which the reconditioning was 
performed (in the United States, use the letters ``USA'');
    (ii) The name and address or symbol of the reconditioner. Symbols, 
if used, must be registered with the Associate Administrator;
    (iii) The last two digits of the year of reconditioning;
    (iv) The letter ``R''; and
    (v) For every packaging successfully passing a leakproofness test, 
the additional letter ``L''.
    (2) When, after reconditioning, the markings required by paragraph 
(a)(1) through (a)(5) of this section no longer appear on the top head 
or the side of the metal drum, the reconditioner must apply them in a 
durable form followed by the markings in paragraph (c)(1) of this 
section. These markings may identify a different performance capability 
than that for which the original design type had been tested and marked, 
but may not identify a greater performance capability. The markings 
applied in accordance with this paragraph may be different from those 
which are permanently marked on the bottom of a drum in accordance with 
paragraph (a)(10) of this section.
    (d) Marking of remanufactured packagings. For remanufactured metal 
drums, if there is no change to the packaging type and no replacement or 
removal of integral structural components, the required markings need 
not be permanent (e.g., embossed). Every other remanufactured drum must 
bear the marks required in paragraphs (a)(1) through (a)(6) of this 
section in a permanent form (e.g., embossed) on the top head or side. If 
the metal thickness marking required in paragraph (a)(9)(i) of this 
section does not appear on the bottom of the drum, or if it is no longer 
valid, the remanufacturer also must mark this information in permanent 
form.
    (1)(i) The United Nations symbol is:

[[Page 200]]

[GRAPHIC] [TIFF OMITTED] TR02FE10.002

    (ii) The circle that surrounds the letters ``u'' and ``n'' may have 
small breaks provided the following provisions are met:
    (A) The total gap space does not exceed 15 percent of the 
circumference of the circle;
    (B) There are no more than four gaps in the circle;
    (C) The spacing between gaps is separated by no less than 20 percent 
of the circumference of the circle (72 degrees); and
    (D) The letters ``u'' and ``n'' appear exactly as depicted in Sec. 
178.503(e)(1)(i) with no gaps.
    (2) Examples of markings for a new packaging are as follows:
    (i) For a fiberboard box designed to contain an inner packaging:
    [GRAPHIC] [TIFF OMITTED] TC02MR91.087
    

(as in Sec. 178.503 (a)(1) through (a)(9) of this subpart).
    (ii) For a steel drum designed to contain liquids:
    [GRAPHIC] [TIFF OMITTED] TC02MR91.088
    

(as in Sec. 178.503 (a)(1) through (a)(10) of this subpart).
    (iii) For a steel drum to transport solids or inner packagings:
    [GRAPHIC] [TIFF OMITTED] TC02MR91.089
    

(as in Sec. 178.503 (a)(1) through (a)(8) of this subpart).
    (3) Examples of markings for reconditioned packagings are as 
follows:
[GRAPHIC] [TIFF OMITTED] TC02MR91.090


(as in Sec. 178.503(c)(1)).
    (f) A manufacturer must mark every UN specification package 
represented as manufactured to meet the requirements of Sec. 178.609 
for packaging of infectious substances with the marks specified in this 
section. The markings

[[Page 201]]

must be durable, legible, and must be readily visible, as specified in 
Sec. 178.3(a). An infectious substance packaging that successfully 
passes the tests conforming to the UN standard must be marked as 
follows:
    (1) The United Nations symbol as illustrated in paragraph (e) of 
this section.
    (2) The code designating the type of packaging and material of 
construction according to the identification codes for packagings 
specified in Sec. 178.502.
    (3) The text ``CLASS 6.2''.
    (4) The last two digits of the year of manufacture of the packaging.
    (5) The country authorizing the allocation of the mark. The letters 
``USA'' indicate the packaging is manufactured and marked in the United 
States in compliance with the provisions of this subchapter.
    (6) The name and address or symbol of the manufacturer or the 
approval agency certifying compliance with subparts L and M of this 
part. Symbols, if used, must be registered with the Associate 
Administrator for Hazardous Materials Safety.
    (7) For packagings meeting the requirements of Sec. 178.609(i)(3), 
the letter ``U'' must be inserted immediately following the marking 
designating the type of packaging and material required in paragraph 
(f)(2) of this section.

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended at 56 FR 66284, 
Dec. 20, 1991; Amdt. 178-102, 59 FR 28493, June 2, 1994; Amdt. 178-106, 
59 FR 67520, 67521, Dec. 29, 1994; Amdt. 178-107, 60 FR 26806, May 18, 
1995; 62 FR 51561, Oct. 1, 1997; 66 FR 45386, Aug. 28, 2001; 67 FR 
61016, Sept. 27, 2002; 67 FR 53143, Aug. 14, 2002; 68 FR 75757, Dec. 31, 
2003; 75 FR 5395, Feb 2, 2010; 75 FR 60339, Sept. 30, 2010]



Sec. 178.504  Standards for steel drums.

    (a) The following are identification codes for steel drums:
    (1) 1A1 for a non-removable head steel drum; and
    (2) 1A2 for a removable head steel drum.
    (b) Construction requirements for steel drums are as follows:
    (1) Body and heads must be constructed of steel sheet of suitable 
type and adequate thickness in relation to the capacity and intended use 
of the drum. Minimum thickness and marking requirements in Sec. Sec. 
173.28(b)(4) and 178.503(a)(9) of this subchapter apply to drums 
intended for reuse.
    (2) Body seams must be welded on drums designed to contain more than 
40 L (11 gallons) of liquids. Body seams must be mechanically seamed or 
welded on drums intended to contain only solids or 40 L (11 gallons) or 
less of liquids.
    (3) Chimes must be mechanically seamed or welded. Separate 
reinforcing rings may be applied.
    (4) The body of a drum of a capacity greater than 60 L (16 gallons) 
may have at least two expanded rolling hoops or two separate rolling 
hoops. If there are separate rolling hoops, they must be fitted tightly 
on the body and so secured that they cannot shift. Rolling hoops may not 
be spot-welded.
    (5) Openings for filling, emptying and venting in the bodies or 
heads of non-removable head (1A1) drums may not exceed 7.0 cm (3 inches) 
in diameter. Drums with larger openings are considered to be of the 
removable head type (1A2). Closures for openings in the bodies and heads 
of drums must be so designed and applied that they will remain secure 
and leakproof under normal conditions of transport. Closure flanges may 
be mechanically seamed or welded in place. Gaskets or other sealing 
elements must be used with closures unless the closure is inherently 
leakproof.
    (6) Closure devices for removable head drums must be so designed and 
applied that they will remain secure and drums will remain leakproof 
under normal conditions of transport. Gaskets or other sealing elements 
must be used with all removable heads.
    (7) If materials used for body, heads, closures, and fittings are 
not in themselves compatible with the contents to be transported, 
suitable internal protective coatings or treatments must be applied. 
These coatings or treatments must retain their protective properties 
under normal conditions of transport.
    (8) Maximum capacity of drum: 450 L (119 gallons).

[[Page 202]]

    (9) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended at 56 FR 66284, 
Dec. 20, 1991; Amdt. 178-110, 60 FR 49111, Sept. 21, 1995]



Sec. 178.505  Standards for aluminum drums.

    (a) The following are the identification codes for aluminum drums:
    (1) 1B1 for a non-removable head aluminum drum; and
    (2) 1B2 for a removable head aluminum drum.
    (b) Construction requirements for aluminum drums are as follows:
    (1) Body and heads must be constructed of aluminum at least 99 
percent pure or an aluminum base alloy. Material must be of suitable 
type and adequate thickness in relation to the capacity and the intended 
use of the drum. Minimum thickness and marking requirements in 
Sec. Sec. 173.28(b)(4) and 178.503(a)(9) of this subchapter apply to 
drums intended for reuse.
    (2) All seams must be welded. Chime seams, if any, must be 
reinforced by the application of separate reinforcing rings.
    (3) The body of a drum of a capacity greater than 60 L (16 gallons) 
may have at least two expanded rolling hoops or two separate rolling 
hoops. If there are separate rolling hoops, the hoops must be fitted 
tightly on the body and so secured that they cannot shift. Rolling hoops 
may not be spot-welded.
    (4) Openings for filling, emptying, or venting in the bodies or 
heads of non-removable head (1B1) drums may not exceed 7.0 cm (3 inches) 
in diameter. Drums with larger openings are considered to be of the 
removable head type (1B2). Closures for openings in the bodies and heads 
of drums must be so designed and applied that they will remain secure 
and leakproof under normal conditions of transport. Closure flanges may 
be welded in place so that the weld provides a leakproof seam. Gaskets 
or other sealing elements must be used with closures unless the closure 
is inherently leakproof.
    (5) Closure devices for removable head drums must be so designed and 
applied that they remain secure and drums remain leakproof under normal 
conditions of transport. Gaskets or other sealing elements must be used 
with all removable heads.
    (6) Maximum capacity of drum: 450 L (119 gallons).
    (7) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended at 56 FR 66284, 
Dec. 20, 1991; Amdt. 178-102, 59 FR 28494, June 2, 1994]



Sec. 178.506  Standards for metal drums other than steel or aluminum.

    (a) The following are the identification codes for metal drums other 
than steel or aluminum:
    (1) 1N1 for a non-removable head metal drum; and
    (2) 1N2 for a removable head metal drum.
    (b) Construction requirements for metal drums other than steel or 
aluminum are as follows:
    (1) Body and heads must be constructed of metal (other than steel or 
aluminum) of suitable type and adequate thickness in relation to the 
capacity and the intended use of the drum. Minimum thickness and marking 
requirements in Sec. Sec. 173.28(b)(4) and 178.503(a)(9) of this 
subchapter apply to drums intended for reuse.
    (2) All seams must be welded. Chime seams, if any, must be 
reinforced by the application of separate reinforcing rings.
    (3) The body of a drum of a capacity greater than 60 L (16 gallons) 
may have at least two expanded rolling hoops or two separate rolling 
hoops. If there are separate rolling hoops, the hoops must be fitted 
tightly on the body and so secured that they cannot shift. Rolling hoops 
may not be spot-welded.
    (4) Openings for filling, emptying, or venting in the bodies or 
heads of non-removable head (1N1) drums may not exceed 7.0 cm (3 inches) 
in diameter. Drums with larger openings are considered to be of the 
removable head type (1N2). Closures for openings in the bodies and heads 
of drums must be so designed and applied that they will remain secure 
and leakproof under normal conditions of transport. Closure flanges may 
be welded in place so that the weld provides a leakproof seam. Gaskets 
or other sealing elements must be used with closures unless the closure 
is inherently leakproof.

[[Page 203]]

    (5) Closure devices for removable head drums must be so designed and 
applied that they remain secure and drums remain leakproof under normal 
conditions of transport. Gaskets or other sealing elements must be used 
with all removable heads.
    (6) Maximum capacity of drum: 450 L (119 gallons).
    (7) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended at 56 FR 66285, 
Dec. 20, 1991; Amdt. 178-102, 59 FR 28494, June 2, 1994]



Sec. 178.507  Standards for plywood drums.

    (a) The identification code for a plywood drum is 1D.
    (b) Construction requirements for plywood drums are as follows:
    (1) The wood used must be well-seasoned, commercially dry and free 
from any defect likely to lessen the effectiveness of the drum for the 
purpose intended. A material other than plywood, of at least equivalent 
strength and durability, may be used for the manufacture of the heads.
    (2) At least two-ply plywood must be used for the body and at least 
three-ply plywood for the heads; the plies must be firmly glued 
together, with their grains crosswise.
    (3) The body and heads of the drum and their joints must be of a 
design appropriate to the capacity of the drum and its intended use.
    (4) In order to prevent sifting of the contents, lids must be lined 
with kraft paper or some other equivalent material which must be 
securely fastened to the lid and extend to the outside along its full 
circumference.
    (5) Maximum capacity of drum: 250 L (66 gallons).
    (6) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended at 57 FR 45465, 
Oct. 1, 1992]



Sec. 178.508  Standards for fiber drums.

    (a) The identification code for a fiber drum is 1G.
    (b) Construction requirements for fiber drums are as follows:
    (1) The body of the drum must be constructed of multiple plies of 
heavy paper or fiberboard (without corrugations) firmly glued or 
laminated together and may include one or more protective layers of 
bitumen, waxed kraft paper, metal foil, plastic material, or similar 
materials.
    (2) Heads must be of natural wood, fiberboard, metal, plywood, 
plastics, or other suitable material and may include one or more 
protective layers of bitumen, waxed kraft paper, metal foil, plastic 
material, or similar material.
    (3) The body and heads of the drum and their joints must be of a 
design appropriate to the capacity and intended use of the drum.
    (4) The assembled packaging must be sufficiently water-resistant so 
as not to delaminate under normal conditions of transport.
    (5) Maximum capacity of drum: 450 L (119 gallons).
    (6) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-106, 
59 FR 67521, Dec. 29, 1994]



Sec. 178.509  Standards for plastic drums and jerricans.

    (a) The following are identification codes for plastic drums and 
jerricans:
    (1) 1H1 for a non-removable head plastic drum;
    (2) 1H2 for a removable head plastic drum;
    (3) 3H1 for a non-removable head jerrican; and
    (4) 3H2 for a removable head jerrican.
    (b) Construction requirements for plastic drums and jerricans are as 
follows:
    (1) The packaging must be manufactured from suitable plastic 
material and be of adequate strength in relation to its capacity and 
intended use. No used material other than production residues or regrind 
from the same manufacturing process may be used unless approved by the 
Associate Administrator. The packaging must be adequately resistant to 
aging and to degradation caused either by the substance contained or by 
ultra-violet radiation. Any permeation of the substance contained may 
not constitute a danger under normal conditions of transport.

[[Page 204]]

    (2) If protection against ultra-violet radiation is required, it 
must be provided by the addition of carbon black or other suitable 
pigments or inhibitors. These additives must be compatible with the 
contents and remain effective throughout the life of the packaging. 
Where use is made of carbon black, pigments or inhibitors other than 
those used in the manufacture of the design type, retesting may be 
omitted if the carbon black content does not exceed 2 percent by mass or 
if the pigment content does not exceed 3 percent by mass; the content of 
inhibitors of ultra-violet radiation is not limited.
    (3) Additives serving purposes other than protection against ultra-
violet radiation may be included in the composition of the plastic 
material provided they do not adversely affect the chemical and physical 
properties of the packaging material.
    (4) The wall thickness at every point of the packaging must be 
appropriate to its capacity and its intended use, taking into account 
the stresses to which each point is liable to be exposed. Minimum 
thickness and marking requirements in Sec. Sec. 173.28(b)(4) and 
178.503(a)(9) of this subchapter apply to drums intended for reuse.
    (5) Openings for filling, emptying and venting in the bodies or 
heads of non-removable head (1H1) drums and jerricans (3H1) may not 
exceed 7.0 cm (3 inches) in diameter. Drums and jerricans with larger 
openings are considered to be of the removable head type (1H2 and 3H2). 
Closures for openings in the bodies or heads of drums and jerricans must 
be so designed and applied that they remain secure and leakproof under 
normal conditions of transport. Gaskets or other sealing elements must 
be used with closures unless the closure is inherently leakproof.
    (6) Closure devices for removable head drums and jerricans must be 
so designed and applied that they remain secure and leakproof under 
normal conditions of transport. Gaskets must be used with all removable 
heads unless the drum or jerrican design is such that when the removable 
head is properly secured, the drum or jerrican is inherently leakproof.
    (7) Maximum capacity of drums and jerricans: 1H1, 1H2: 450 L (119 
gallons); 3H1, 3H2: 60 L (16 gallons).
    (8) Maximum net mass: 1H1, 1H2: 400 kg (882 pounds); 3H1, 3H2: 120 
kg (265 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-102, 
59 FR 28494, June 2, 1994; 64 FR 10782, Mar. 5, 1999; 66 FR 45386, Aug. 
28, 2001]



Sec. 178.510  Standards for wooden barrels.

    (a) The following are identification codes for wooden barrels:
    (1) 2C1 for a bung type wooden barrel; and
    (2) 2C2 for a slack type (removable head) wooden barrel.
    (b) Construction requirements for wooden barrels are as follows:
    (1) The wood used must be of good quality, straight-grained, well-
seasoned and free from knots, bark, rotten wood, sapwood or other 
defects likely to lessen the effectiveness of the barrel for the purpose 
intended.
    (2) The body and heads must be of a design appropriate to the 
capacity and intended use of the barrel.
    (3) Staves and heads must be sawn or cleft with the grain so that no 
annual ring extends over more than half the thickness of a stave or 
head.
    (4) Barrel hoops must be of steel or iron of good quality. The hoops 
of 2C2 barrels may be of a suitable hardwood.
    (5) For wooden barrels 2C1, the diameter of the bung-hole may not 
exceed half the width of the stave in which it is placed.
    (6) For wooden barrels 2C2, heads must fit tightly into crozes.
    (7) Maximum capacity of barrel: 250 L (66 gallons).
    (8) Maximum net mass: 400 kg (882 pounds).



Sec. 178.511  Standards for aluminum and steel jerricans.

    (a) The following are identification codes for aluminum and steel 
jerricans:
    (1) 3A1 for a non-removable head steel jerrican;
    (2) 3A2 for a removable head steel jerrican;
    (3) 3B1 for a non-removable head aluminum jerrican; and

[[Page 205]]

    (4) 3B2 for a removable head aluminum jerrican.
    (b) Construction requirements for aluminum and steel jerricans are 
as follows:
    (1) For steel jerricans the body and heads must be constructed of 
steel sheet of suitable type and adequate thickness in relation to the 
capacity of the jerrican and its intended use. Minimum thickness and 
marking requirements in Sec. Sec. 173.28(b)(4) and 178.503(a)(9) of 
this subchapter apply to jerricans intended for reuse.
    (2) For aluminum jerricans the body and heads must be constructed of 
aluminum at least 99% pure or of an aluminum base alloy. Material must 
be of a type and of adequate thickness in relation to the capacity of 
the jerrican and to its intended use.
    (3) Chimes of all jerricans must be mechanically seamed or welded. 
Body seams of jerricans intended to carry more than 40 L (11 gallons) of 
liquid must be welded. Body seams of jerricans intended to carry 40 L 
(11 gallons) or less must be mechanically seamed or welded.
    (4) Openings in jerricans (3A1) may not exceed 7.0 cm (3 inches) in 
diameter. Jerricans with larger openings are considered to be of the 
removable head type. Closures must be so designed that they remain 
secure and leakproof under normal conditions of transport. Gaskets or 
other sealing elements must be used with closures, unless the closure is 
inherently leakproof.
    (5) If materials used for body, heads, closures and fittings are not 
in themselves compatible with the contents to be transported, suitable 
internal protective coatings or treatments must be applied. These 
coatings or treatments must retain their protective properties under 
normal conditions of transport.
    (6) Maximum capacity of jerrican: 60 L (16 gallons).
    (7) Maximum net mass: 120 kg (265 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-102, 
59 FR 28494, June 2, 1994; Amdt. 178-119, 62 FR 24742, May 6, 1997]



Sec. 178.512  Standards for steel or aluminum boxes.

    (a) The following are identification codes for steel or aluminum 
boxes:
    (1) 4A for a steel box; and
    (2) 4B for an aluminum box.
    (b) Construction requirements for steel or aluminum boxes are as 
follows:
    (1) The strength of the metal and the construction of the box must 
be appropriate to the capacity and intended use of the box.
    (2) Boxes must be lined with fiberboard or felt packing pieces or 
must have an inner liner or coating of suitable material in accordance 
with subpart C of part 173 of this subchapter. If a double seamed metal 
liner is used, steps must be taken to prevent the ingress of materials, 
particularly explosives, into the recesses of the seams.
    (3) Closures may be of any suitable type, and must remain secure 
under normal conditions of transport.
    (4) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-106, 
59 FR 67521, Dec. 29, 1994]



Sec. 178.513  Standards for boxes of natural wood.

    (a) The following are the identification codes for boxes of natural 
wood:
    (1) 4C1 for an ordinary box; and
    (2) 4C2 for a box with sift-proof walls.
    (b) Construction requirements for boxes of natural wood are as 
follows:
    (1) The wood used must be well-seasoned, commercially dry and free 
from defects that would materially lessen the strength of any part of 
the box. The strength of the material used and the method of 
construction must be appropriate to the capacity and intended use of the 
box. The tops and bottoms may be made of water-resistant reconstituted 
wood such as hard board, particle board or other suitable type.
    (2) Fastenings must be resistant to vibration experienced under 
normal conditions of transportation. End grain nailing must be avoided 
whenever practicable. Joints which are likely to be highly stressed must 
be made using clenched or annular ring nails or equivalent fastenings.

[[Page 206]]

    (3) Each part of the 4C2 box must be one piece or equivalent. Parts 
are considered equivalent to one piece when one of the following methods 
of glued assembly is used: Linderman joint, tongue and groove joint, 
ship lap or rabbet joint, or butt joint with at least two corrugated 
metal fasteners at each joint.
    (4) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-106, 
59 FR 67521, Dec. 29, 1994]



Sec. 178.514  Standards for plywood boxes.

    (a) The identification code for a plywood box is 4D.
    (b) Construction requirements for plywood boxes are as follows:
    (1) Plywood used must be at least 3 ply. It shall be made from well-
seasoned rotary cut, sliced or sawn veneer, commercially dry and free 
from defects that would materially lessen the strength of the box. The 
strength of the material used and the method of construction must be 
appropriate to the capacity and intended use of the box. All adjacent 
plies must be glued with water-resistant adhesive. Other suitable 
materials may be used together with plywood in the construction of 
boxes. Boxes must be nailed or secured to corner posts or ends or 
assembled with other equally suitable devices.
    (2) Maximum net mass: 400 kg (882 pounds).



Sec. 178.515  Standards for reconstituted wood boxes.

    (a) The identification code for a reconstituted wood box is 4F.
    (b) Construction requirements for reconstituted wood boxes are as 
follows:
    (1) The walls of boxes must be made of water-resistant, 
reconstituted wood such as hardboard, particle board, or other suitable 
type. The strength of the material used and the method of construction 
must be appropriate to the capacity of the boxes and their intended use.
    (2) Other parts of the box may be made of other suitable materials.
    (3) Boxes must be securely assembled by means of suitable devices.
    (4) Maximum net mass: 400 kg (882 pounds).



Sec. 178.516  Standards for fiberboard boxes.

    (a) The identification code for a fiberboard box is 4G.
    (b) Construction requirements for fiberboard boxes are as follows:
    (1) Strong, solid or double-faced corrugated fiberboard (single or 
multi-wall) must be used, appropriate to the capacity and intended use 
of the box. The water resistance of the outer surface must be such that 
the increase in mass, as determined in a test carried out over a period 
of 30 minutes by the Cobb method of determining water absorption, is not 
greater than 155 g per square meter (0.0316 pounds per square foot)--see 
ISO 535 (IBR, see Sec. 171.7 of this subchapter). Fiberboard must have 
proper bending qualities. Fiberboard must be cut, creased without 
cutting through any thickness of fiberboard, and slotted so as to permit 
assembly without cracking, surface breaks, or undue bending. The fluting 
of corrugated fiberboard must be firmly glued to the facings.
    (2) The ends of boxes may have a wooden frame or be entirely of wood 
or other suitable material. Reinforcements of wooden battens or other 
suitable material may be used.
    (3) Manufacturing joints. (i) Manufacturing joints in the bodies of 
boxes must be--
    (A) Taped;
    (B) Lapped and glued; or
    (C) Lapped and stitched with metal staples.
    (ii) Lapped joints must have an appropriate overlap.
    (4) Where closing is effected by gluing or taping, a water resistant 
adhesive must be used.
    (5) Boxes must be designed so as to provide a snug fit to the 
contents.
    (6) Maximum net mass: 400 kg (882 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, and amended by Amdt. 178-99, 
58 FR 51534, Oct. 1, 1993; Amdt. 178-106, 59 FR 67521, Dec. 29, 1994; 68 
FR 75758, Dec. 31, 2003]



Sec. 178.517  Standards for plastic boxes.

    (a) The following are identification codes for plastic boxes:
    (1) 4H1 for an expanded plastic box; and
    (2) 4H2 for a solid plastic box.

[[Page 207]]

    (b) Construction requirements for plastic boxes are as follows:
    (1) The box must be manufactured from suitable plastic material and 
be of adequate strength in relation to its capacity and intended use. 
The box must be adequately resistant to aging and to degradation caused 
either by the substance contained or by ultra-violet radiation.
    (2) An expanded plastic box must consist of two parts made of a 
molded expanded plastic material: a bottom section containing cavities 
for the inner receptacles, and a top section covering and interlocking 
with the bottom section. The top and bottom sections must be so designed 
that the inner receptacles fit snugly. The closure cap for any inner 
receptacle may not be in contact with the inside of the top section of 
the box.
    (3) For transportation, an expanded plastic box must be closed with 
a self-adhesive tape having sufficient tensile strength to prevent the 
box from opening. The adhesive tape must be weather-resistant and its 
adhesive compatible with the expanded plastic material of the box. Other 
closing devices at least equally effective may be used.
    (4) For solid plastic boxes, protection against ultra-violet 
radiation, if required, must be provided by the addition of carbon black 
or other suitable pigments or inhibitors. These additives must be 
compatible with the contents and remain effective throughout the life of 
the box. Where use is made of carbon black pigment or inhibitors other 
than those used in the manufacture of the tested design type, retesting 
may be waived if the carbon black content does not exceed 2 percent by 
mass or if the pigment content does not exceed 3 percent by mass; the 
content of inhibitors of ultra-violet radiation is not limited.
    (5) Additives serving purposes other than protection against ultra-
violet radiation may be included in the composition of the plastic 
material if they do not adversely affect the material of the box. 
Addition of these additives does not change the design type.
    (6) Solid plastic boxes must have closure devices made of a suitable 
material of adequate strength and so designed as to prevent the box from 
unintentionally opening.
    (7) Maximum net mass 4H1: 60 kg (132 pounds); 4H2: 400 kg (882 
pounds).



Sec. 178.518  Standards for woven plastic bags.

    (a) The following are identification codes for woven plastic bags:
    (1) 5H1 for an unlined or non-coated woven plastic bag;
    (2) 5H2 for a sift-proof woven plastic bag; and
    (3) 5H3 for a water-resistant woven plastic bag.
    (b) Construction requirements for woven plastic fabric bags are as 
follows:
    (1) Bags must be made from stretched tapes or monofilaments of a 
suitable plastic material. The strength of the material used and the 
construction of the bag must be appropriate to the capacity and intended 
use of the bag.
    (2) If the fabric is woven flat, the bags must be made by sewing or 
some other method ensuring closure of the bottom and one side. If the 
fabric is tubular, the bag must be closed by sewing, weaving, or some 
other equally strong method of closure.
    (3) Bags, sift-proof, 5H2 must be made sift-proof by appropriate 
means such as use of paper or a plastic film bonded to the inner surface 
of the bag or one or more separate inner liners made of paper or plastic 
material.
    (4) Bags, water-resistant, 5H3: To prevent the entry of moisture, 
the bag must be made waterproof by appropriate means, such as separate 
inner liners of water-resistant paper (e.g., waxed kraft paper, double-
tarred kraft paper or plastic-coated kraft paper), or plastic film 
bonded to the inner or outer surface of the bag, or one or more inner 
plastic liners.
    (5) Maximum net mass: 50 kg (110 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, and amended by Amdt. 178-99, 
58 FR 51534, Oct. 1, 1993]



Sec. 178.519  Standards for plastic film bags.

    (a) The identification code for a plastic film bag is 5H4.
    (b) Construction requirements for plastic film bags are as follows:

[[Page 208]]

    (1) Bags must be made of a suitable plastic material. The strength 
of the material used and the construction of the bag must be appropriate 
to the capacity and the intended use of the bag. Joints and closures 
must be capable of withstanding pressures and impacts liable to occur 
under normal conditions of transportation.
    (2) Maximum net mass: 50 kg (110 pounds).



Sec. 178.520  Standards for textile bags.

    (a) The following are identification codes for textile bags:
    (1) 5L1 for an unlined or non-coated textile bag;
    (2) 5L2 for a sift-proof textile bag; and
    (3) 5L3 for a water-resistant textile bag.
    (b) Construction requirements for textile bags are as follows:
    (1) The textiles used must be of good quality. The strength of the 
fabric and the construction of the bag must be appropriate to the 
capacity and intended use of the bag.
    (2) Bags, sift-proof, 5L2: The bag must be made sift-proof, by 
appropriate means, such as by the use of paper bonded to the inner 
surface of the bag by a water-resistant adhesive such as bitumen, 
plastic film bonded to the inner surface of the bag, or one or more 
inner liners made of paper or plastic material.
    (3) Bags, water-resistant, 5L3: To prevent entry of moisture, the 
bag must be made waterproof by appropriate means, such as by the use of 
separate inner liners of water-resistant paper (e.g., waxed kraft paper, 
tarred paper, or plastic-coated kraft paper), or plastic film bonded to 
the inner surface of the bag, or one or more inner liners made of 
plastic material or metalized film or foil.
    (4) Maximum net mass: 50 kg (110 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended at 56 FR 66285, 
Dec. 20, 1991]



Sec. 178.521  Standards for paper bags.

    (a) The following are identification codes for paper bags:
    (1) 5M1 for a multi-wall paper bag; and
    (2) 5M2 for a multi-wall water-resistant paper bag.
    (b) Construction requirements for paper bags are as follows:
    (1) Bags must be made of a suitable kraft paper, or of an equivalent 
paper with at least three plies. The strength of the paper and the 
construction of the bag must be appropriate to the capacity and intended 
use of the bag. Seams and closures must be sift-proof.
    (2) Paper bags 5M2: To prevent the entry of moisture, a bag of four 
plies or more must be made waterproof by the use of either a water-
resistant ply as one of the two outermost plies or a water-resistant 
barrier made of a suitable protective material between the two outermost 
plies. A 5M2 bag of three plies must be made waterproof by the use of a 
water-resistant ply as the outermost ply. When there is danger of the 
lading reacting with moisture, or when it is packed damp, a waterproof 
ply or barrier, such as double-tarred kraft paper, plastics-coated kraft 
paper, plastics film bonded to the inner surface of the bag, or one or 
more inner plastics liners, must also be placed next to the substance. 
Seams and closures must be waterproof.
    (3) Maximum net mass: 50 kg (110 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended at 56 FR 66285, 
Dec. 20, 1991; Amdt. 178-106, 59 FR 67521, Dec. 29, 1994]



Sec. 178.522  Standards for composite packagings with inner plastic
receptacles.

    (a) The following are the identification codes for composite 
packagings with inner plastic receptacles:
    (1) 6HA1 for a plastic receptacle within a protective steel drum;
    (2) 6HA2 for a plastic receptacle within a protective steel crate or 
box;
    (3) 6HB1 for a plastic receptacle within a protective aluminum drum.
    (4) 6HB2 for a plastic receptacle within a protective aluminum crate 
or box.
    (5) 6HC for a plastic receptacle within a protective wooden box.
    (6) 6HD1 for a plastic receptacle within a protective plywood drum;
    (7) 6HD2 for a plastic receptacle within a protective plywood box;
    (8) 6HG1 for a plastic receptacle within a protective fiber drum;

[[Page 209]]

    (9) 6HG2 for a plastic receptacle within a protective fiberboard 
box;
    (10) 6HH1 for a plastic receptacle within a protective plastic drum; 
and
    (11) 6HH2 for a plastic receptacle within a protective plastic box.
    (b) Construction requirements for composite packagings with inner 
receptacles of plastic are as follows:
    (1) Inner receptacles must be constructed under the applicable 
construction requirements prescribed in Sec. 178.509(b) (1) through (7) 
of this subpart.
    (2) The inner plastic receptacle must fit snugly inside the outer 
packaging, which must be free of any projections which may abrade the 
plastic material.
    (3) Outer packagings must be constructed as follows:
    (i) 6HA1 or 6HB1: Protective packaging must conform to the 
requirements for steel drums in Sec. 178.504(b) of this subpart, or 
aluminum drums in Sec. 178.505(b) of this subpart.
    (ii) 6HA2 or 6HB2: Protective packagings with steel or aluminum 
crate must conform to the requirements for steel or aluminum boxes found 
in Sec. 178.512(b) of this subpart.
    (iii) 6HC protective packaging must conform to the requirements for 
wooden boxes in Sec. 178.513(b) of this subpart.
    (iv) 6HD1: Protective packaging must conform to the requirements for 
plywood drums, in Sec. 178.507(b) of this subpart.
    (v) 6HD2: Protective packaging must conform to the requirements of 
plywood boxes, in Sec. 178.514(b) of this subpart.
    (vi) 6HG1: Protective packaging must conform to the requirements for 
fiber drums, in Sec. 178.508(b) of this subpart.
    (vii) 6HG2: protective packaging must conform to the requirements 
for fiberboard boxes, in Sec. 178.516(b) of this subpart.
    (viii) 6HH1: Protective packaging must conform to the requirements 
for plastic drums, in Sec. 178.509(b).
    (ix) 6HH2: Protective packaging must conform to the requirements for 
plastic boxes, in Sec. 178.517(b).
    (4) Maximum capacity of inner receptacles is as follows: 6HA1, 6HB1, 
6HD1, 6HG1, 6HH1--250 L (66 gallons); 6HA2, 6HB2, 6HC, 6HD2, 6HG2, 
6HH2--60 L (16 gallons).
    (5) Maximum net mass is as follows: 6HA1, 6HB1, 6HD1, 6HG1, 6HH1--
400kg (882 pounds); 6HB2, 6HC, 6HD2, 6HG2, 6HH2--75 kg (165 pounds).

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-106, 
59 FR 67521, Dec. 29, 1994]



Sec. 178.523  Standards for composite packagings with inner glass, 
porcelain, or stoneware receptacles.

    (a) The following are identification codes for composite packagings 
with inner receptacles of glass, porcelain, or stoneware:
    (1) 6PA1 for glass, porcelain, or stoneware receptacles within a 
protective steel drum;
    (2) 6PA2 for glass, porcelain, or stoneware receptacles within a 
protective steel crate or box;
    (3) 6PB1 for glass, porcelain, or stoneware receptacles within a 
protective aluminum drum;
    (4) 6PB2 for glass, porcelain, or stoneware receptacles within a 
protective aluminum crate or box;
    (5) 6PC for glass, porcelain, or stoneware receptacles within a 
protective wooden box;
    (6) 6PD1 for glass, porcelain, or stoneware receptacles within a 
protective plywood drum;
    (7) 6PD2 for glass, porcelain, or stoneware receptacles within a 
protective wickerwork hamper;
    (8) 6PG1 for glass, porcelain, or stoneware receptacles within a 
protective fiber drum;
    (9) 6PG2 for glass, porcelain, or stoneware receptacles within a 
protective fiberboard box;
    (10) 6PH1 for glass, porcelain, or stoneware receptacles within a 
protective expanded plastic packaging; and
    (11) 6PH2 for glass, porcelain, or stoneware receptacles within a 
protective solid plastic packaging.
    (b) Construction requirements for composite packagings with inner 
receptacles of glass, porcelain, or stoneware are as follows:
    (1) Inner receptacles must conform to the following requirements:
    (i) Receptacles must be of suitable form (cylindrical or pear-
shaped), be made of good quality materials free from any defect that 
could impair their

[[Page 210]]

strength, and be firmly secured in the outer packaging.
    (ii) Any part of a closure likely to come into contact with the 
contents of the receptacle must be resistant to those contents. Closures 
must be fitted so as to be leakproof and secured to prevent any 
loosening during transportation. Vented closures must conform to Sec. 
173.24(f) of this subchapter.
    (2) Protective packagings must conform to the following 
requirements:
    (i) For receptacles with protective steel drum 6PAl, the drum must 
comply with Sec. 178.504(b) of this subpart. However, the removable lid 
required for this type of packaging may be in the form of a cap.
    (ii) For receptacles with protective packaging of steel crate or 
steel box 6PA2, the protective packaging must conform to the following:
    (A) Section 178.512(b) of this subpart.
    (B) In the case of cylindrical receptacles, the protective packaging 
must, when upright, rise above the receptacle and its closure; and
    (C) If the protective crate surrounds a pear-shaped receptacle and 
is of matching shape, the protective packaging must be fitted with a 
protective cover (cap).
    (iii) For receptacles with protective aluminum drum 6PB1, the 
requirements of Sec. 178.505(b) of this subpart apply to the protective 
packaging.
    (iv) For receptacles with protective aluminum box or crate 6PB2, the 
requirements of Sec. 178.512(b) of this subpart apply to the protective 
packaging.
    (v) For receptacles with protective wooden box 6PC, the requirements 
of Sec. 178.513(b) of this subpart apply to the protective packaging.
    (vi) For receptacles with protective plywood drum 6PD1, the 
requirements of Sec. 178.507(b) of this subpart apply to the protective 
packaging.
    (vii) For receptacles with protective wickerwork hamper 6PD2, the 
wickerwork hamper must be properly made with material of good quality. 
The hamper must be fitted with a protective cover (cap) so as to prevent 
damage to the receptacle.
    (viii) For receptacles with protective fiber drum 6PG1, the drum 
must conform to the requirements of Sec. 178.508(b) of this subpart.
    (ix) For receptacles with protective fiberboard box 6PG2, the 
requirements of Sec. 178.516(b) of this subpart apply to the protective 
packaging.
    (x) For receptacles with protective solid plastic or expanded 
plastic packaging 6PH1 or 6PH2, the requirements of Sec. 178.517(b) of 
this subpart apply to the protective packaging. Solid protective plastic 
packaging must be manufactured from high-density polyethylene from some 
other comparable plastic material. The removable lid required for this 
type of packaging may be a cap.
    (3) Quantity limitations are as follows:
    (i) Maximum net capacity for packaging for liquids: 60 L (16 
gallons).
    (ii) Maximum net mass for packagings for solids: 75 kg (165 pounds).



          Subpart M_Testing of Non-bulk Packagings and Packages

    Source: Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, unless otherwise 
noted.



Sec. 178.600  Purpose and scope.

    This subpart prescribes certain testing requirements for 
performance-oriented packagings identified in subpart L of this part.

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, and amended by Amdt. 178-99, 
58 FR 51534, Oct. 1, 1993]



Sec. 178.601  General requirements.

    (a) General. The test procedures prescribed in this subpart are 
intended to ensure that packages containing hazardous materials can 
withstand normal conditions of transportation and are considered minimum 
requirements. Each packaging must be manufactured and assembled so as to 
be capable of successfully passing the prescribed tests and of 
conforming to the requirements of Sec. 173.24 of this subchapter at all 
times while in transportation.
    (b) Responsibility. It is the responsibility of the packaging 
manufacturer to assure that each package is capable of passing the 
prescribed tests. To the extent that a package assembly function, 
including final closure, is performed by the person who offers a 
hazardous material for transportation,

[[Page 211]]

that person is responsible for performing the function in accordance 
with Sec. Sec. 173.22 and 178.2 of this subchapter.
    (c) Definitions. For the purpose of this subpart:
    (1) Design qualification testing is the performance of the tests 
prescribed in Sec. 178.603, Sec. 178.604, Sec. 178.605, Sec. 
178.606, Sec. 178.607, Sec. 178.608, or Sec. 178.609, as applicable, 
for each new or different packaging, at the start of production of that 
packaging.
    (2) Periodic retesting is the performance of the drop, 
leakproofness, hydrostatic pressure, and stacking tests, as applicable, 
as prescribed in Sec. 178.603, Sec. 178.604, Sec. 178.605, or Sec. 
178.606, respectively, at the frequency specified in paragraph (e) of 
this section. For infectious substances packagings required to meet the 
requirements of Sec. 178.609, periodic retesting is the performance of 
the tests specified in Sec. 178.609 at the frequency specified in 
paragraph (e) of this section.
    (3) Production testing is the performance of the leakproofness test 
prescribed in Sec. 178.604 of this subpart on each single or composite 
packaging intended to contain a liquid.
    (4) A different packaging is one that differs (i.e. is not 
identical) from a previously produced packaging in structural design, 
size, material of construction, wall thickness or manner of construction 
but does not include:
    (i) A packaging which differs only in surface treatment;
    (ii) A combination packaging which differs only in that the outer 
packaging has been successfully tested with different inner packagings. 
A variety of such inner packagings may be assembled in this outer 
packaging without further testing;
    (iii) A plastic packaging which differs only with regard to 
additives which conform to Sec. 178.509(b)(3) or Sec. 178.517(b) (4) 
or (5) of this part;
    (iv) A combination packaging with inner packagings conforming to the 
provisions of paragraph (g) of this section;
    (v) Packagings which differ from the design type only in their 
lesser design height; or
    (vi) For a steel drum, variations in design elements which do not 
constitute a different design type under the provisions of paragraph 
(g)(8) of this section.
    (d) Design qualification testing. The packaging manufacturer shall 
achieve successful test results for the design qualification testing at 
the start of production of each new or different packaging.
    (e) Periodic retesting. The packaging manufacturer must achieve 
successful test results for the periodic retesting at intervals 
established by the manufacturer of sufficient frequency to ensure that 
each packaging produced by the manufacturer is capable of passing the 
design qualification tests. Changes in retest frequency are subject to 
the approval of the Associate Administrator for Hazardous Materials 
Safety. For single or composite packagings, the periodic retests must be 
conducted at least once every 12 months. For combination packagings, the 
periodic retests must be conducted at least once every 24 months. For 
infectious substances packagings, the periodic retests must be conducted 
at least once every 24 months.
    (f) Test samples. The manufacturer shall conduct the design 
qualification and periodic tests prescribed in this subpart using random 
samples of packagings, in the numbers specified in the appropriate test 
section. In addition, the leakproofness test, when required, shall be 
performed on each packaging produced by the manufacturer, and each 
packaging prior to reuse under Sec. 173.28 of this subchapter, by the 
reconditioner.
    (g) Selective testing. The selective testing of packagings that 
differ only in minor respects from a tested type is permitted as 
described in this section. For air transport, packagings must comply 
with Sec. 173.27(c)(1) and (c)(2) of this subchapter.
    (1) Selective testing of combination packagings. Variation 1. 
Variations are permitted in inner packagings of a tested combination 
package, without further testing of the package, provided an equivalent 
level of performance is maintained and, when a package is altered under 
Variation 1 after October 1, 2010, the methodology used to determine 
that the inner packaging,

[[Page 212]]

including closure, maintains an equivalent level of performance is 
documented in writing by the person certifying compliance with this 
paragraph and retained in accordance with paragraph (l) of this section. 
Permitted variations are as follows:
    (i) Inner packagings of equivalent or smaller size may be used 
provided--
    (A) The inner packagings are of similar design to the tested inner 
packagings (i.e. shape--round, rectangular, etc.);
    (B) The material of construction of the inner packagings (glass, 
plastic, metal, etc.) offers resistance to impact and stacking forces 
equal to or greater than that of the originally tested inner packaging;
    (C) The inner packagings have the same or smaller openings and the 
closure is of similar design (e.g., screw cap, friction lid, etc.);
    (D) Sufficient additional cushioning material is used to take up 
void spaces and to prevent significant moving of the inner packagings;
    (E) Inner packagings are oriented within the outer packaging in the 
same manner as in the tested package; and,
    (F) The gross mass of the package does not exceed that originally 
tested.
    (ii) A lesser number of the tested inner packagings, or of the 
alternative types of inner packagings identified in paragraph (g)(1)(i) 
of this section, may be used provided sufficient cushioning is added to 
fill void space(s) and to prevent significant moving of the inner 
packagings.
    (2) Selective testing of combination packagings. Variation 2. 
Articles or inner packagings of any type, for solids or liquids, may be 
assembled and transported without testing in an outer packaging under 
the following conditions:
    (i) The outer packaging must have been successfully tested in 
accordance with Sec. 178.603 with fragile (e.g. glass) inner packagings 
containing liquids at the Packing Group I drop height;
    (ii) The total combined gross mass of inner packagings may not 
exceed one-half the gross mass of inner packagings used for the drop 
test;
    (iii) The thickness of cushioning material between inner packagings 
and between inner packagings and the outside of the packaging may not be 
reduced below the corresponding thickness in the originally tested 
packaging; and when a single inner packaging was used in the original 
test, the thickness of cushioning between inner packagings may not be 
less than the thickness of cushioning between the outside of the 
packaging and the inner packaging in the original test. When either 
fewer or smaller inner packagings are used (as compared to the inner 
packagings used in the drop test), sufficient additional cushioning 
material must be used to take up void spaces.
    (iv) The outer packaging must have successfully passed the stacking 
test set forth in Sec. 178.606 of this subpart when empty, i.e., 
without either inner packagings or cushioning materials. The total mass 
of identical packages must be based on the combined mass of inner 
packagings used for the drop test;
    (v) Inner packagings containing liquids must be completely 
surrounded with a sufficient quantity of absorbent material to absorb 
the entire liquid contents of the inner packagings;
    (vi) When the outer packaging is intended to contain inner 
packagings for liquids and is not leakproof, or is intended to contain 
inner packagings for solids and is not siftproof, a means of containing 
any liquid or solid contents in the event of leakage must be provided in 
the form of a leakproof liner, plastic bag, or other equally efficient 
means of containment. For packagings containing liquids, the absorbent 
material required in paragraph (g)(2)(v) of this section must be placed 
inside the means of containing liquid contents; and
    (vii) Packagings must be marked in accordance with Sec. 178.503 of 
this part as having been tested to Packing Group I performance for 
combination packagings. The marked maximum gross mass may not exceed the 
sum of the mass of the outer packaging plus one half the mass of the 
filled inner packagings of the tested combination packaging. In 
addition, the marking required by Sec. 178.503(a)(2) of this part must 
include the letter ``V''.

[[Page 213]]

    (3) Variation 3. Packagings other than combination packagings which 
are produced with reductions in external dimensions (i.e., length, width 
or diameter) of up to 25 percent of the dimensions of a tested packaging 
may be used without further testing provided an equivalent level of 
performance is maintained. The packagings must, in all other respects 
(including wall thicknesses), be identical to the tested design-type. 
The marked gross mass (when required) must be reduced in proportion to 
the reduction in volume.
    (4) Variation 4. Variations are permitted in outer packagings of a 
tested design-type combination packaging, without further testing, 
provided an equivalent level of performance is maintained, as follows:
    (i) Each external dimension (length, width and height) is less than 
or equal to the corresponding dimension of the tested design-type;
    (ii) The structural design of the tested outer packaging (i.e. 
methods of construction, materials of construction, strength 
characteristics of materials of construction, method of closure and 
material thicknesses) is maintained;
    (iii) The inner packagings are identical to the inner packagings 
used in the tested design type except that their size and mass may be 
less; and they are oriented within the outer packaging in the same 
manner as in the tested packaging;
    (iv) The same type or design of absorbent materials, cushioning 
materials and any other components necessary to contain and protect 
inner packagings, as used in the tested design type, are maintained. The 
thickness of cushioning material between inner packagings and between 
inner packagings and the outside of the packaging may not be less than 
the thicknesses in the tested design type packaging; and
    (v) Sufficient additional cushioning material is used to take up 
void spaces and to prevent significant moving of the inner packagings.

An outer packaging qualifying for use in transport in accordance with 
all of the above conditions may also be used without testing to 
transport inner packagings substituted for the originally tested inner 
packagings in accordance with the conditions set out in Variation 1 in 
paragraph (g)(1) of this section.
    (5) Variation 5. Single packagings (i.e., non-bulk packagings other 
than combination packagings), that differ from a tested design type only 
to the extent that the closure device or gasketing differs from that 
used in the originally tested design type, may be used without further 
testing, provided an equivalent level of performance is maintained, 
subject to the following conditions (the qualifying tests):
    (i) A packaging with the replacement closure devices or gasketing 
must successfully pass the drop test specified in Sec. 178.603 in the 
orientation which most severely tests the integrity of the closure or 
gasket;
    (ii) When intended to contain liquids, a packaging with the 
replacement closure devices or gasketing must successfully pass the 
leakproofness test specified in Sec. 178.604, the hydrostatic pressure 
test specified in Sec. 178.605, and the stacking test specified in 
Sec. 178.606.

Replacement closures and gasketings qualified under the above test 
requirements are authorized without additional testing for packagings 
described in paragraph (g)(3) of this section. Replacement closures and 
gasketings qualified under the above test requirements also are 
authorized without additional testing for different tested design types 
packagings of the same type as the originally tested packaging, provided 
the original design type tests are more severe or comparable to tests 
which would otherwise be conducted on the packaging with the replacement 
closures or gasketings. (For example: The packaging used in the 
qualifying tests has a lesser packaging wall thickness than the 
packaging with replacement closure devices or gasketing; the gross mass 
of the packaging used in the qualifying drop test equals or exceeds the 
mass for which the packaging with replacement closure devices or 
gasketing was tested; the packaging used in the qualifying drop test was 
dropped from the same or greater height than the height from which the 
packaging with replacement closure devices or gasketing was dropped in 
design type tests; and the specific gravity

[[Page 214]]

of the substance used in the qualifying drop test was the same or 
greater than the specific gravity of the liquid used in the design type 
tests of the packaging with replacement closure devices or gasketing.)
    (6) The provisions in Variations 1, 2, and 4 in paragraphs (g)(1), 
(2) and (4) of this section for combination packagings may be applied to 
packagings containing articles, where the provisions for inner 
packagings are applied analogously to the articles. In this case, inner 
packagings need not comply with Sec. 173.27(c)(1) and (c)(2) of this 
subchapter.
    (7) Approval of selective testing. In addition to the provisions of 
Sec. 178.601(g)(1) through (g)(6) of this subpart, the Associate 
Administrator may approve the selective testing of packagings that 
differ only in minor respects from a tested type.
    (8) For a steel drum with a capacity greater than 12 L (3 gallons) 
manufactured from low carbon, cold-rolled sheet steel meeting ASTM 
designations A 366/A 366M or A 568/A 568M, variations in elements other 
than the following design elements are considered minor and do not 
constitute a different drum design type, or ``different packaging'' as 
defined in paragraph (c) of this section for which design qualification 
testing and periodic retesting are required. Minor variations authorized 
without further testing include changes in the identity of the supplier 
of component material made to the same specifications, or the original 
manufacturer of a DOT specification or UN standard drum to be 
remanufactured. A change in any one or more of the following design 
elements constitutes a different drum design type:
    (i) The packaging type and category of the original drum and the 
remanufactured drum, i.e., 1A1 or 1A2;
    (ii) The style, (i.e., straight-sided or tapered);
    (iii) Except as provided in paragraph (g)(3) of this section, the 
rated (marked) capacity and outside dimensions;
    (iv) The physical state for which the packaging was originally 
approved (e.g., tested for solids or liquids);
    (v) An increase in the marked level of performance of the original 
drum (i.e., to a higher packing group, hydrostatic test pressure, or 
specific gravity to which the packaging has been tested);
    (vi) Type of side seam welding;
    (vii) Type of steel;
    (viii) An increase greater than 10% or any decrease in the steel 
thickness of the head, body, or bottom;
    (ix) End seam type, (e.g., triple or double seam);
    (x) A reduction in the number of rolling hoops (beads) which equal 
or exceed the diameter over the chimes;
    (xi) The location, type or size, and material of closures (other 
than the cover of UN 1A2 drums);
    (xii) The location (e.g., from the head to the body), type (e.g., 
mechanically seamed or welded flange), and materials of closure (other 
than the cover of UN 1A2 drums); and
    (xiii) For UN 1A2 drums:
    (A) Gasket material (e.g., plastic), or properties affecting the 
performance of the gasket;
    (B) Configuration or dimensions of the gasket;
    (C) Closure ring style including bolt size (e.g., square or round 
back, 0.625 inches bolt); and
    (D) Closure ring thickness,
    (E) Width of lugs or extensions in crimp/lug cover.
    (h) Approval of equivalent packagings. A packaging having 
specifications different from those in Sec. Sec. 178.504-178.523 of 
this part, or which is tested using methods or test intervals, other 
than those specified in subpart M of this part, may be used if approved 
by the Associate Administrator. Such packagings must be shown to be 
equally effective, and testing methods used must be equivalent.
    (i) Proof of compliance. Notwithstanding the periodic retest 
intervals specified in paragraph (e) of this section, the Associate 
Administrator may at any time require demonstration of compliance by a 
manufacturer, through testing in accordance with this subpart, that 
packagings meet the requirements of this subpart. As required by the 
Associate Administrator, the manufacturer shall either--
    (1) Conduct performance tests, or have tests conducted by an 
independent testing facility, in accordance with this subpart; or

[[Page 215]]

    (2) Supply packagings, in quantities sufficient to conduct tests in 
accordance with this subpart, to the Associate Administrator or a 
designated representative of the Associate Administrator.
    (j) Coatings. If an inner treatment or coating of a packaging is 
required for safety reasons, the manufacturer shall design the packaging 
so that the treatment or coating retains its protective properties even 
after withstanding the tests prescribed by this subpart.
    (k) Number of test samples. Except as provided in this section, one 
test sample must be used for each test performed under this subpart.
    (1) Stainless steel drums. Provided the validity of the test results 
is not affected, a person may perform the design qualification testing 
of stainless steel drums using three (3) samples rather than the 
specified eighteen (18) samples under the following provisions:
    (i) The packaging must be tested in accordance with this subpart by 
subjecting each of the three containers to the following sequence of 
tests:
    (A) The stacking test in Sec. 178.606,
    (B) The leakproofness test in Sec. 178.604,
    (C) The hydrostatic pressure test in Sec. 178.608, and
    (D) Diagonal top chime and flat on the side drop tests in Sec. 
178.603. Both drop tests may be conducted on the same sample.
    (ii) For periodic retesting of stainless steel drums, a reduced 
sample size of one container is authorized.
    (2) Packagings other than stainless steel drums. Provided the 
validity of the test results is not affected, several tests may be 
performed on one sample with the approval of the Associate 
Administrator.
    (l) Record retention. Following each design qualification test and 
each periodic retest on a packaging, a test report must be prepared. The 
test report must be maintained at each location where the packaging is 
manufactured and each location where the design qualification tests are 
conducted, for as long as the packaging is produced and for at least two 
years thereafter, and at each location where the periodic retests are 
conducted until such tests are successfully performed again and a new 
test report produced. In addition, a copy of the test report must be 
maintained by a person certifying compliance with this part. The test 
report must be made available to a user of a packaging or a 
representative of the Department upon request. The test report, at a 
minimum, must contain the following information:
    (1) Name and address of test facility;
    (2) Name and address of applicant (where appropriate);
    (3) A unique test report identification;
    (4) Date of the test report;
    (5) Manufacturer of the packaging;
    (6) Description of the packaging design type (e.g. dimensions, 
materials, closures, thickness, etc.), including methods of manufacture 
(e.g. blow molding) and which may include drawing(s) and/or 
photograph(s);
    (7) Maximum capacity;
    (8) Characteristics of test contents, e.g. viscosity and relative 
density for liquids and particle size for solids;
    (9) Test descriptions and results; and
    (10) Signed with the name and title of signatory.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended at 56 FR 66285, 
Dec. 20, 1991; 57 FR 45465, Oct. 1, 1992; Amdt. 178-102, 59 FR 28494, 
June 2, 1994; Amdt. 178-106, 59 FR 67521, 67522, Dec. 29, 1994; Amdt. 
178-117, 61 FR 50628, Sept. 26, 1996; 66 FR 45386, Aug. 28, 2001; 67 FR 
53143, Aug. 14, 2002; 68 FR 75758, Dec. 31, 2003; 68 FR 61942, Oct. 30, 
2003; 75 FR 5396, Feb 2, 2010; 75 FR 60339, Sept. 30, 2010]



Sec. 178.602  Preparation of packagings and packages for testing.

    (a) Except as otherwise provided in this subchapter, each packaging 
and package must be closed in preparation for testing and tests must be 
carried out in the same manner as if prepared for transportation, 
including inner packagings in the case of combination packagings.
    (b) For the drop and stacking test, inner and single-unit 
receptacles other than bags must be filled to not less than 95% of 
maximum capacity (see Sec. 171.8 of this subchapter) in the case of 
solids and not less than 98% of maximum in the case of liquids. Bags 
containing solids shall be filled to the maximum mass at which they may 
be used. The material to be transported in the packagings may be 
replaced by a non-hazardous material, except for

[[Page 216]]

chemical compatibility testing or where this would invalidate the 
results of the tests.
    (c) If the material to be transported is replaced for test purposes 
by a non-hazardous material, the material used must be of the same or 
higher specific gravity as the material to be carried, and its other 
physical properties (grain, size, viscosity) which might influence the 
results of the required tests must correspond as closely as possible to 
those of the hazardous material to be transported. Water may also be 
used for the liquid drop test under the conditions specified in Sec. 
178.603(e) of this subpart. It is permissible to use additives, such as 
bags of lead shot, to achieve the requisite total package mass, so long 
as they are placed so that the test results are not affected.
    (d) Paper or fiberboard packagings must be conditioned for at least 
24 hours immediately prior to testing in an atmosphere maintained--
    (1) At 50 percent 2 percent relative humidity, 
and at a temperature of 23 [deg]C2 [deg]C (73 
[deg]F4 [deg]F). Average values should fall within 
these limits. Short-term fluctuations and measurement limitations may 
cause individual measurements to vary by up to 5 
percent relative humidity without significant impairment of test 
reproducibility;
    (2) At 65 percent 2 percent relative humidity, 
and at a temperature of 20 [deg]C2 [deg]C (68 
[deg]F4 [deg]F), or 27 [deg]C2 [deg]C (81 [deg]F4 [deg]F). 
Average values should fall within these limits. Short-term fluctuations 
and measurement limitations may cause individual measurements to vary by 
up to 5 percent relative humidity without 
significant impairment of test reproducibility; or
    (3) For testing at periodic intervals only (i.e., other than initial 
design qualification testing), at ambient conditions.
    (e) Except as otherwise provided, each packaging must be closed in 
preparation for testing in the same manner as if prepared for actual 
shipment. All closures must be installed using proper techniques and 
torques.
    (f) Bung-type barrels made of natural wood must be left filled with 
water for at least 24 hours before the tests.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended at 56 FR 66286, 
Dec. 20, 1991; Amdt. 178-106, 59 FR 67522, Dec. 29, 1994; 69 FR 76186, 
Dec. 20, 2004; 71 FR 78635, Dec. 29, 2006]



Sec. 178.603  Drop test.

    (a) General. The drop test must be conducted for the qualification 
of all packaging design types and performed periodically as specified in 
Sec. 178.601(e). For other than flat drops, the center of gravity of 
the test packaging must be vertically over the point of impact. Where 
more than one orientation is possible for a given drop test, the 
orientation most likely to result in failure of the packaging must be 
used. The number of drops required and the packages' orientations are as 
follows:

------------------------------------------------------------------------
                                 No. of tests      Drop orientation of
          Packaging               (samples)              samples
------------------------------------------------------------------------
Steel drums, Aluminum drums,   Six--(three for  First drop (using three
 Metal drums (other than        each drop).      samples): The package
 steel or aluminum), Steel                       must strike the target
 Jerricans, Plywood drums,                       diagonally on the chime
 Wooden barrels, Fiber drums,                    or, if the packaging
 Plastic drums and Jerricans,                    has no chime, on a
 Composite packagings which                      circumferential seam or
 are in the shape of a drum.                     an edge. Second drop
                                                 (using the other three
                                                 samples): The package
                                                 must strike the target
                                                 on the weakest part not
                                                 tested by the first
                                                 drop, for example a
                                                 closure or, for some 7
                                                 cylindrical drums, the
                                                 welded longitudinal
                                                 seam of the drum body.
Boxes of natural wood,         Five--(one for   First drop: Flat on the
 Plywood boxes, Reconstituted   each drop).      bottom (using the first
 wood boxes, Fiberboard                          sample). Second drop:
 boxes, Plastic boxes, Steel                     Flat on the top (using
 or aluminum boxes, Composite                    the second sample).
 packagings which are in the                     Third drop: Flat on the
 shape of a box.                                 long side (using the
                                                 third sample). Fourth
                                                 drop: Flat on the short
                                                 side (using the fourth
                                                 sample). Fifth drop: On
                                                 a corner (using the
                                                 fifth sample).
Bags--single-ply with a side   Three--(three    First drop: Flat on a
 seam.                          drops per bag).  wide face (using all
                                                 three samples). Second
                                                 drop: Flat on a narrow
                                                 face (using all three
                                                 samples). Third drop:
                                                 On an end of the bag
                                                 (using all three
                                                 samples).
Bags--single-ply without a     Three--(two      First drop: Flat on a
 side seam, or multi-ply.       drops per bag).  wide face (using all
                                                 three samples). Second
                                                 drop: On an end of the
                                                 bag (using all three
                                                 samples).
------------------------------------------------------------------------

    (b) Exceptions. For testing of single or composite packagings 
constructed of stainless steel, nickel, or monel at periodic intervals 
only (i.e., other than

[[Page 217]]

design qualification testing), the drop test may be conducted with two 
samples, one sample each for the two drop orientations. These samples 
may have been previously used for the hydrostatic pressure or stacking 
test. Exceptions for the number of steel and aluminum packaging samples 
used for conducting the drop test are subject to the approval of the 
Associate Administrator.
    (c) Special preparation of test samples for the drop test. (1) 
Testing of plastic drums, plastic jerricans, plastic boxes other than 
expanded polystyrene boxes, composite packagings (plastic material), and 
combination packagings with plastic inner packagings other than plastic 
bags intended to contain solids or articles must be carried out when the 
temperature of the test sample and its contents has been reduced to -18 
[deg]C (0 [deg]F) or lower. Test liquids must be kept in the liquid 
state, if necessary, by the addition of anti-freeze. Water/anti-freeze 
solutions with a minimum specific gravity of 0.95 for testing at -18 
[deg]C (0 [deg]F) or lower are considered acceptable test liquids. Test 
samples prepared in this way are not required to be conditioned in 
accordance with Sec. 178.602(d).
    (d) Target. The target must be a rigid, non-resilient, flat and 
horizontal surface.
    (e) Drop height. Drop heights, measured as the vertical distance 
from the target to the lowest point on the package, must be equal to or 
greater than the drop height determined as follows:
    (1) For solids and liquids, if the test is performed with the solid 
or liquid to be transported or with a non-hazardous material having 
essentially the same physical characteristic, the drop height must be 
determined according to packing group, as follows:
    (i) Packing Group I: 1.8 m (5.9 feet).
    (ii) Packing Group II: 1.2 m (3.9 feet).
    (iii) Packing Group III: 0.8 m (2.6 feet).
    (2) For liquids in single packagings and for inner packagings of 
combination packagings, if the test is performed with water:
    (i) Where the materials to be carried have a specific gravity not 
exceeding 1.2, drop height must be determined according to packing 
group, as follows:
    (A) Packing Group I: 1.8 m (5.9 feet).
    (B) Packing Group II: 1.2 m (3.9 feet).
    (C) Packing Group III: 0.8 m (2.6 feet).
    (ii) Where the materials to be transported have a specific gravity 
exceeding 1.2, the drop height must be calculated on the basis of the 
specific gravity (SG) of the material to be carried, rounded up to the 
first decimal, as follows:
    (A) Packing Group I: SG x 1.5 m (4.9 feet).
    (B) Packing Group II: SG x 1.0 m (3.3 feet).
    (C) Packing Group III: SG x 0.67 m (2.2 feet).
    (f) Criteria for passing the test. A package is considered to 
successfully pass the drop tests if for each sample tested--
    (1) For packagings containing liquid, each packaging does not leak 
when equilibrium has been reached between the internal and external 
pressures, except for inner packagings of combination packagings when it 
is not necessary that the pressures be equalized;
    (2) For removable head drums for solids, the entire contents are 
retained by an inner packaging (e.g., a plastic bag) even if the closure 
on the top head of the drum is no longer sift-proof;
    (3) For a bag, neither the outermost ply nor an outer packaging 
exhibits any damage likely to adversely affect safety during transport;
    (4) The packaging or outer packaging of a composite or combination 
packaging must not exhibit any damage likely to affect safety during 
transport. Inner receptacles, inner packagings, or articles must remain 
completely within the outer packaging and there must be no leakage of 
the filling substance from the inner receptacles or inner packagings;
    (5) Any discharge from a closure is slight and ceases immediately 
after impact with no further leakage; and
    (6) No rupture is permitted in packagings for materials in Class 1 
which

[[Page 218]]

would permit spillage of loose explosive substances or articles from the 
outer packaging.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended at 56 FR 66286, 
Dec. 20, 1991; 57 FR 45465, Oct. 1, 1992; Amdt. 178-99, 58 FR 51534, 
Oct. 1, 1993; Amdt. 178-106, 59 FR 67522, Dec. 29, 1994; 65 FR 50462, 
Aug. 18, 2000; 66 FR 45386, Aug. 28, 2001; 67 FR 61016, Sept. 27, 2002; 
69 FR 76186, Dec. 20, 2004; 76 FR 3389, Jan. 19, 2011]



Sec. 178.604  Leakproofness test.

    (a) General. The leakproofness test must be performed with 
compressed air or other suitable gases on all packagings intended to 
contain liquids, except that:
    (1) The inner receptacle of a composite packaging may be tested 
without the outer packaging provided the test results are not affected; 
and
    (2) This test is not required for inner packagings of combination 
packagings.
    (b) Number of packagings to be tested--(1) Production testing. All 
packagings subject to the provisions of this section must be tested and 
must pass the leakproofness test:
    (i) Before they are first used in transportation; and
    (ii) Prior to reuse, when authorized for reuse by Sec. 173.28 of 
this subchapter.
    (2) Design qualification and periodic testing. Three samples of each 
different packaging must be tested and must pass the leakproofness test. 
Exceptions for the number of samples used in conducting the 
leakproofness test are subject to the approval of the Associate 
Administrator.
    (c) Special preparation--(1) For design qualification and periodic 
testing, packagings must be tested with closures in place. For 
production testing, packagings need not have their closures in place. 
Removable heads need not be installed during production testing.
    (2) For testing with closures in place, vented closures must either 
be replaced by similar non-vented closures or the vent must be sealed.
    (d) Test method. The packaging must be restrained under water while 
an internal air pressure is applied; the method of restraint must not 
affect the results of the test. The test must be conducted, for other 
than production testing, for a minimum time of five minutes. Other 
methods, at least equally effective, may be used in accordance with 
appendix B of this part.
    (e) Pressure applied. An internal air pressure (gauge) must be 
applied to the packaging as indicated for the following packing groups:
    (1) Packing Group I: Not less than 30 kPa (4 psi).
    (2) Packing Group II: Not less than 20 kPa (3 psi).
    (3) Packing Group III: Not less than 20 kPa (3 psi).
    (f) Criteria for passing the test. A packaging passes the test if 
there is no leakage of air from the packaging.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended at 56 FR 66286, 
Dec. 20, 1991; Amdt. 178-106, 59 FR 67522, Dec. 29, 1994; 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.605  Hydrostatic pressure test.

    (a) General. The hydrostatic pressure test must be conducted for the 
qualification of all metal, plastic, and composite packaging design 
types intended to contain liquids and be performed periodically as 
specified in Sec. 178.601(e). This test is not required for inner 
packagings of combination packagings. For internal pressure requirements 
for inner packagings of combination packagings intended for 
transportation by aircraft, see Sec. 173.27(c) of this subchapter.
    (b) Number of test samples. Three test samples are required for each 
different packaging. For packagings constructed of stainless steel, 
monel, or nickel, only one sample is required for periodic retesting of 
packagings. Exceptions for the number of aluminum and steel sample 
packagings used in conducting the hydrostatic pressure test are subject 
to the approval of the Associate Administrator.
    (c) Special preparation of receptacles for testings. Vented closures 
must either be replaced by similar non-vented closures or the vent must 
be sealed.
    (d) Test method and pressure to be applied. Metal packagings and 
composite packagings other than plastic (e.g., glass, porcelain or 
stoneware), including their closures, must be subjected to the test 
pressure for 5 minutes. Plastic packagings and composite packagings 
(plastic material), including their closures, must be subjected to the 
test

[[Page 219]]

pressure for 30 minutes. This pressure is the one to be marked as 
required in Sec. 178.503(a)(5). The receptacles must be supported in a 
manner that does not invalidate the test. The test pressure must be 
applied continuously and evenly, and it must be kept constant throughout 
the test period. In addition, packagings intended to contain hazardous 
materials of Packing Group I must be tested to a minimum test pressure 
of 250 kPa (36 psig). The hydraulic pressure (gauge) applied, taken at 
the top of the receptacle, and determined by any one of the following 
methods must be:
    (1) Not less than the total gauge pressure measured in the packaging 
(i.e., the vapor pressure of the filling material and the partial 
pressure of the air or other inert gas minus 100 kPa (15 psi)) at 55 
[deg]C (131 [deg]F), multiplied by a safety factor of 1.5. This total 
gauge pressure must be determined on the basis of a maximum degree of 
filling in accordance with Sec. 173.24a(d) of this subchapter and a 
filling temperature of 15 [deg]C (59 [deg]F);
    (2) Not less than 1.75 times the vapor pressure at 50 [deg]C (122 
[deg]F) of the material to be transported minus 100 kPa (15 psi) but 
with a minimum test pressure of 100 kPa (15 psig); or
    (3) Not less than 1.5 times the vapor pressure at 55 [deg]C (131 
[deg]F) of the material to be transported minus 100 kPa (15 psi), but 
with a minimum test pressure of 100 kPa (15 psig).

Packagings intended to contain hazardous materials of Packing Group I 
must be tested to a minimum test pressure of 250 kPa (36 psig).
    (e) Criteria for passing the test. A package passes the hydrostatic 
test if, for each test sample, there is no leakage of liquid from the 
package.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended at 56 FR 66286, 
Dec. 20, 1991; Amdt. 178-99, 58 FR 51534, Oct. 1, 1993; Amdt. 178-102, 
59 FR 28494, June 2, 1994; 65 FR 50462, Aug. 18, 2000; 66 FR 45386, 
45390, Aug. 28, 2001; 73 FR 57007, Oct. 1, 2008]



Sec. 178.606  Stacking test.

    (a) General. All packaging design types other than bags must be 
subjected to a stacking test.
    (b) Number of test samples. Three test samples are required for each 
different packaging. For periodic retesting of packagings constructed of 
stainless steel, monel, or nickel, only one test sample is required. 
Exceptions for the number of aluminum and steel sample packagings used 
in conducting the stacking test are subject to the approval of the 
Associate Administrator. Notwithstanding the provisions of Sec. 
178.602(a) of this subpart, combination packagings may be subjected to 
the stacking test without their inner packagings, except where this 
would invalidate the results of the test.
    (c) Test method--(1) Design qualification testing. The test sample 
must be subjected to a force applied to the top surface of the test 
sample equivalent to the total weight of identical packages which might 
be stacked on it during transport; where the contents of the test sample 
are non-hazardous liquids with specific gravities different from that of 
the liquid to be transported, the force must be calculated based on the 
specific gravity that will be marked on the packaging. The minimum 
height of the stack, including the test sample, must be 3.0 m (10 feet). 
The duration of the test must be 24 hours, except that plastic drums, 
jerricans, and composite packagings 6HH intended for liquids shall be 
subjected to the stacking test for a period of 28 days at a temperature 
of not less than 40 [deg]C (104 [deg]F). Alternative test methods which 
yield equivalent results may be used if approved by the Associate 
Administrator. In guided load tests, stacking stability must be assessed 
after completion of the test by placing two filled packagings of the 
same type on the test sample. The stacked packages must maintain their 
position for one hour. Plastic packagings must be cooled to ambient 
temperature before this stacking stability assessment.
    (2) Periodic retesting. The test sample must be tested in accordance 
with:
    (i) Section 178.606(c)(1) of this subpart; or
    (ii) The packaging may be tested using a dynamic compression testing 
machine. The test must be conducted at room temperature on an empty, 
unsealed packaging. The test sample must be centered on the bottom 
platen of the testing machine. The top platen

[[Page 220]]

must be lowered until it comes in contact with the test sample. 
Compression must be applied end to end. The speed of the compression 
tester must be one-half inch plus or minus one-fourth inch per minute. 
An initial preload of 50 pounds must be applied to ensure a definite 
contact between the test sample and the platens. The distance between 
the platens at this time must be recorded as zero deformation. The force 
A to then be applied must be calculated using the formula:

Liquids: A = (n-1) [w + (s x v x 8.3 x .98)] x 1.5;
Solids: A = (n-1) (m x 2.2 x 1.5)

Where:

A = applied load in pounds
m = the certified maximum gross mass for the container in kilograms.
n = minimum number of containers that, when stacked, reach a height of 3 
          meters.
s = specific gravity of lading.
w = maximum weight of one empty container in pounds.
v = actual capacity of container (rated capacity + outage) in gallons.

And:

8.3 corresponds to the weight in pounds of 1.0 gallon of water.
.98 corresponds to the minimum filling percentage of the maximum 
          capacity for liquids.
1.5 is a compensation factor that converts the static load of the 
          stacking test into a load suitable for dynamic compression 
          testing.
2.2 is the conversion factor for kilograms to pounds.
    (d) Criteria for passing the test. No test sample may leak. In 
composite packagings or combination packagings, there must be no leakage 
of the filling substance from the inner receptacle, or inner packaging. 
No test sample may show any deterioration which could adversely affect 
transportation safety or any distortion likely to reduce its strength, 
cause instability in stacks of packages, or cause damage to inner 
packagings likely to reduce safety in transportation. For the dynamic 
compression test, a container passes the test if, after application of 
the required load, there is no buckling of the sidewalls sufficient to 
cause damage to its expected contents; in no case may the maximum 
deflection exceed one inch.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended at 56 FR 66286, 
Dec. 20, 1991; 57 FR 45465, Oct. 1, 1992; Amdt. 178-102, 59 FR 28494, 
June 2, 1994; Amdt. 178-106, 59 FR 67522, Dec. 29, 1994; 65 FR 58632, 
Sept. 29, 2000; 66 FR 45386, Aug. 28, 2001; 70 FR 34076, June 13, 2005; 
72 FR 55696, Oct. 1, 2007]



Sec. 178.607  Cooperage test for bung-type wooden barrels.

    (a) Number of samples. One barrel is required for each different 
packaging.
    (b) Method of testing. Remove all hoops above the bilge of an empty 
barrel at least two days old.
    (c) Criteria for passing the test. A packaging passes the cooperage 
test only if the diameter of the cross-section of the upper part of the 
barrel does not increase by more than 10 percent.



Sec. 178.608  Vibration standard.

    (a) Each packaging must be capable of withstanding, without rupture 
or leakage, the vibration test procedure outlined in this section.
    (b) Test method. (1) Three sample packagings, selected at random, 
must be filled and closed as for shipment.
    (2) The three samples must be placed on a vibrating platform that 
has a vertical or rotary double-amplitude (peak-to-peak displacement) of 
one inch. The packages should be constrained horizontally to prevent 
them from falling off the platform, but must be left free to move 
vertically, bounce and rotate.
    (3) The test must be performed for one hour at a frequency that 
causes the package to be raised from the vibrating platform to such a 
degree that a piece of material of approximately 1.6 mm (0.063 inch) 
thickness (such as steel strapping or paperboard) can be passed between 
the bottom of any package and the platform.
    (4) Immediately following the period of vibration, each package must 
be removed from the platform, turned on its side and observed for any 
evidence of leakage.
    (5) Other methods, at least equally effective, may be used, if 
approved by the Associate Administrator.
    (c) Criteria for passing the test. A packaging passes the vibration 
test if there

[[Page 221]]

is no rupture or leakage from any of the packages. No test sample should 
show any deterioration which could adversely affect transportation 
safety or any distortion liable to reduce packaging strength.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended at 56 FR 66286, 
Dec. 20, 1991; 66 FR 45386, Aug. 28, 2001]



Sec. 178.609  Test requirements for packagings for infectious 
substances.

    (a) Samples of each packaging must be prepared for testing as 
described in paragraph (b) of this section and then subjected to the 
tests in paragraphs (d) through (i) of this section.
    (b) Samples of each packaging must be prepared as for transport 
except that a liquid or solid infectious substance should be replaced by 
water or, where conditioning at -18 [deg]C (0 [deg]F) is specified, by 
water/antifreeze. Each primary receptacle must be filled to 98 percent 
capacity. Packagings for live animals should be tested with the live 
animal being replaced by an appropriate dummy of similar mass.
    (c) Packagings prepared as for transport must be subjected to the 
tests in Table I of this paragraph (c), which, for test purposes, 
categorizes packagings according to their material characteristics. For 
outer packagings, the headings in Table I relate to fiberboard or 
similar materials whose performance may be rapidly affected by moisture; 
plastics that may embrittle at low temperature; and other materials, 
such as metal, for which performance is not significantly affected by 
moisture or temperature. Where a primary receptacle and a secondary 
packaging of an inner packaging are made of different materials, the 
material of the primary receptacle determines the appropriate test. In 
instances where a primary receptacle is made of more than one material, 
the material most likely to be damaged determines the appropriate test.

                                             Table I--Tests Required
----------------------------------------------------------------------------------------------------------------
                             Material of                                            Tests required
----------------------------------------------------------------------------------------------------------------
             Outer packaging                    Inner packaging             Refer to para. (d)
----------------------------------------------------------------------------------------------------   Refer to
 Fiberboard     Plastics        Other       Plastics        Other      (d)   (e)   (f)      (g)       para. (h)
----------------------------------------------------------------------------------------------------------------
X             ............  ............  X             ............  ....  X     X     When dry     X
                                                                                         ice is
                                                                                         used
X             ............  ............  ............  X             ....  X     ....  ...........  X
              X             ............  X             ............  ....  ....  X     ...........  X
              X             ............  ............  X             ....  ....  X     ...........  X
              ............  X             X             ............  ....  ....  X     ...........  X
              ............  X             ............  X             X     ....  ....  ...........  X
----------------------------------------------------------------------------------------------------------------

    (d) Samples must be subjected to free-fall drops onto a rigid, 
nonresilient, flat, horizontal surface from a height of 9 m (30 feet).
    The drops must be performed as follows:
    (1) Where the samples are in the shape of a box, five samples must 
be dropped, one in each of the following orientation:
    (i) Flat on the base;
    (ii) Flat on the top;
    (iii) Flat on the longest side;
    (iv) Flat on the shortest side; and
    (v) On a corner.
    (2) Where the samples are in the shape of a drum, three samples must 
be dropped, one in each of the following orientations:
    (i) Diagonally on the top chime, with the center of gravity directly 
above the point of impact;
    (ii) Diagonally on the base chime; and
    (iii) Flat on the side.
    (3) While the sample should be released in the required orientation, 
it is accepted that for aerodynamic reasons the impact may not take 
place in that orientation.
    (4) Following the appropriate drop sequence, there must be no 
leakage from the primary receptacle(s) which should remain protected by 
absorbent material in the secondary packaging.

[[Page 222]]

    (e) The samples must be subjected to a water spray to simulate 
exposure to rainfall of approximately 50 mm (2 inches) per hour for at 
least one hour. They must then be subjected to the test described in 
paragraph (d) of this section.
    (f) The sample must be conditioned in an atmosphere of -18 [deg]C (0 
[deg]F) or less for a period of at least 24 hours and within 15 minutes 
of removal from that atmosphere be subjected to the test described in 
paragraph (d) of this section. Where the sample contains dry ice, the 
conditioning period may be reduced to 4 hours.
    (g) Where packaging is intended to contain dry ice, a test 
additional to that specified in paragraph (d) or (e) or (f) of this 
section must be carried out. One sample must be stored so that all the 
dry ice dissipates and then be subjected to the test described in 
paragraph (d) of this section.
    (h) Packagings with a gross mass of 7 kg (15 pounds) or less should 
be subjected to the tests described in paragraph (h)(1) of this section 
and packagings with a gross mass exceeding 7 kg (15 pounds) to the tests 
in paragraph (h)(2) of this section.
    (1) Samples must be placed on a level, hard surface. A cylindrical 
steel rod with a mass of at least 7 kg (15 pounds), a diameter not 
exceeding 38 mm (1.5 inches), and, at the impact end edges, a radius not 
exceeding 6 mm (0.2 inches), must be dropped in a vertical free fall 
from a height of 1 m (3 feet), measured from the impact end of the 
sample's impact surface. One sample must be placed on its base. A second 
sample must be placed in an orientation perpendicular to that used for 
the first. In each instance, the steel rod must be aimed to impact the 
primary receptacle(s). For a successful test, there must be no leakage 
from the primary receptacle(s) following each impact.
    (2) Samples must be dropped onto the end of a cylindrical steel rod. 
The rod must be set vertically in a level, hard surface. It must have a 
diameter of 38 mm (1.5 inches) and a radius not exceeding 6 mm (0.2 
inches) at the edges of the upper end. The rod must protrude from the 
surface a distance at least equal to that between the primary 
receptacle(s) and the outer surface of the outer packaging with a 
minimum of 200 mm (7.9 inches). One sample must be dropped in a vertical 
free fall from a height of 1 m (3 feet), measured from the top of the 
steel rod. A second sample must be dropped from the same height in an 
orientation perpendicular to that used for the first. In each instance, 
the packaging must be oriented so the steel rod will impact the primary 
receptacle(s). For a successful test, there must be no leakage from the 
primary receptacle(s) following each impact.
    (i) Variations. The following variations in the primary receptacles 
placed within the secondary packaging are allowed without additional 
testing of the completed package. An equivalent level of performance 
must be maintained.
    (1) Variation 1. Primary receptacles of equivalent or smaller size 
as compared to the tested primary receptacles may be used provided they 
meet all of the following conditions:
    (i) The primary receptacles are of similar design to the tested 
primary receptacle (e.g., shape: round, rectangular, etc.).
    (ii) The material of construction of the primary receptacle (glass, 
plastics, metal, etc.) offers resistance to impact and a stacking force 
equal to or greater than that of the originally tested primary 
receptacle.
    (iii) The primary receptacles have the same or smaller openings and 
the closure is of similar design (e.g., screw cap, friction lid, etc.).
    (iv) Sufficient additional cushioning material is used to fill void 
spaces and to prevent significant movement of the primary receptacles.
    (v) Primary receptacles are oriented within the intermediate 
packaging in the same manner as in the tested package.
    (2) Variation 2. A lesser number of the tested primary receptacles, 
or of the alternative types of primary receptacles identified in 
paragraph (i)(1) of this section, may be used provided sufficient 
cushioning is added to fill the void space(s) and to prevent significant 
movement of the primary receptacles.

[[Page 223]]

    (3) Variation 3. Primary receptacles of any type may be placed 
within a secondary packaging and shipped without testing in the outer 
packaging provided all of the following conditions are met:
    (i) The secondary and outer packaging combination must be 
successfully tested in accordance with paragraphs (a) through (h) of 
this section with fragile (e.g., glass) inner receptacles.
    (ii) The total combined gross weight of inner receptacles may not 
exceed one-half the gross weight of inner receptacles used for the drop 
test in paragraph (d) of this section.
    (iii) The thickness of cushioning material between inner receptacles 
and between inner receptacles and the outside of the secondary packaging 
may not be reduced below the corresponding thicknesses in the originally 
tested packaging. If a single inner receptacle was used in the original 
test, the thickness of cushioning between the inner receptacles must be 
no less than the thickness of cushioning between the outside of the 
secondary packaging and the inner receptacle in the original test. When 
either fewer or smaller inner receptacles are used (as compared to the 
inner receptacles used in the drop test), sufficient additional 
cushioning material must be used to fill the void.
    (iv) The outer packaging must pass the stacking test in Sec. 
178.606 while empty. The total weight of identical packages must be 
based on the combined mass of inner receptacles used in the drop test in 
paragraph (d) of this section.
    (v) For inner receptacles containing liquids, an adequate quantity 
of absorbent material must be present to absorb the entire liquid 
contents of the inner receptacles.
    (vi) If the outer packaging is intended to contain inner receptacles 
for liquids and is not leakproof, or is intended to contain inner 
receptacles for solids and is not sift proof, a means of containing any 
liquid or solid contents in the event of leakage must be provided. This 
can be a leakproof liner, plastic bag, or other equally effective means 
of containment.
    (vii) In addition, the marking required in Sec. 178.503(f) of this 
subchapter must be followed by the letter ``U''.

[Amdt. 178-97, 55 FR 52723, Dec. 21, 1990, as amended by Amdt. 178-111, 
60 FR 48787, Sept. 20, 1995; 67 FR 53143, Aug. 14, 2002; 69 FR 54046, 
Sept. 7, 2004]



              Subpart N_IBC Performance-Oriented Standards



Sec. 178.700  Purpose, scope and definitions.

    (a) This subpart prescribes requirements applying to IBCs intended 
for the transportation of hazardous materials. Standards for these 
packagings are based on the UN Recommendations.
    (b) Terms used in this subpart are defined in Sec. 171.8 of this 
subchapter and in paragraph (c) of this section.
    (c) The following definitions pertain to the IBC standards in this 
subpart.
    (1) Body means the receptacle proper (including openings and their 
closures, but not including service equipment) that has a volumetric 
capacity of not more than 3 cubic meters (3,000 L, 793 gallons, or 106 
cubic feet).
    (2) Service equipment means filling and discharge, pressure relief, 
safety, heating and heat-insulating devices and measuring instruments.
    (3) Structural equipment means the reinforcing, fastening, handling, 
protective or stabilizing members of the body or stacking load bearing 
structural members (such as metal cages).
    (4) Maximum permissible gross mass means the mass of the body, its 
service equipment, structural equipment and the maximum net mass (see 
Sec. 171.8 of this subchapter).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended by Amdt. 178-108, 
60 FR 40038, Aug. 4, 1995; 66 FR 45386, 45387, Aug. 28, 2001; 73 FR 
57008, Oct. 1, 2008; 75 FR 5396, Feb. 2, 2010]



Sec. 178.702  IBC codes.

    (a) Intermediate bulk container code designations consist of: two 
numerals specified in paragraph (a)(1) of this section; followed by the 
capital letter(s) specified in paragraph (a)(2) of this section; 
followed, when specified in an individual section, by a numeral 
indicating the category of intermediate bulk container.

[[Page 224]]

    (1) IBC code number designations are as follows:

------------------------------------------------------------------------
                                    For solids, discharged
                                  --------------------------
                                                   Under
               Type                             pressure of  For liquids
                                    by gravity   more than
                                                   10 kPa
                                                (1.45 psig)
------------------------------------------------------------------------
Rigid............................           11           21           31
Flexible.........................           13
------------------------------------------------------------------------

    (2) Intermediate bulk container code letter designations are as 
follows:

``A'' means steel (all types and surface treatments).
``B'' means aluminum.
``C'' means natural wood.
``D'' means plywood.
``F'' means reconstituted wood.
``G'' means fiberboard.
``H'' means plastic.
``L'' means textile.
``M'' means paper, multiwall.
``N'' means metal (other than steel or aluminum).

    (b) For composite IBCs, two capital letters are used in sequence 
following the numeral indicating IBC design type. The first letter 
indicates the material of the IBC inner receptacle. The second letter 
indicates the material of the outer IBC. For example, 31HA1 is a 
composite IBC with a plastic inner receptacle and a steel outer 
packaging.

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.703  Marking of IBCs.

    (a) The manufacturer shall:
    (1) Mark every IBC in a durable and clearly visible manner. The 
marking may be applied in a single line or in multiple lines provided 
the correct sequence is followed with the information required by this 
section in letters, numerals and symbols of at least 12 mm in height. 
This minimum marking size applies only to IBCs manufactured after 
October 1, 2001). The following information is required in the sequence 
presented:
    (i) Except as provided in Sec. 178.503(e)(1)(ii), the United 
Nations symbol as illustrated in Sec. 178.503(e)(1)(i). For metal IBCs 
on which the marking is stamped or embossed, the capital letters ``UN'' 
may be applied instead of the symbol.
    (ii) The code number designating IBC design type according to Sec. 
178.702(a). The letter ``W'' must follow the IBC design type 
identification code on an IBC when the IBC differs from the requirements 
in subpart N of this part, or is tested using methods other than those 
specified in this subpart, and is approved by the Associate 
Administrator in accordance with the provisions in Sec. 178.801(i).
    (iii) A capital letter identifying the performance standard under 
which the design type has been successfully tested, as follows:
    (A) X--for IBCs meeting Packing Group I, II and III tests;
    (B) Y--for IBCs meeting Packing Group II and III tests; and
    (C) Z--for IBCs meeting only Packing Group III tests.
    (iv) The month (designated numerically) and year (last two digits) 
of manufacture.
    (v) The country authorizing the allocation of the mark. The letters 
`USA' indicate that the IBC is manufactured and marked in the United 
States in compliance with the provisions of this subchapter.
    (vi) The name and address or symbol of the manufacturer or the 
approval agency certifying compliance with subparts N and O of this 
part. Symbols, if used, must be registered with the Associate 
Administrator.
    (vii) The stacking test load in kilograms (kg). For IBCs not 
designed for stacking, the figure ``0'' must be shown.
    (viii) The maximum permissible gross mass in kg.
    (2) The following are examples of symbols and required markings:
    (i) For a metal IBC containing solids discharged by gravity made 
from steel:

[[Page 225]]

[GRAPHIC] [TIFF OMITTED] TR26JY94.000

    (ii) For a flexible IBC containing solids discharged by gravity and 
made from woven plastic with a liner:
[GRAPHIC] [TIFF OMITTED] TR26JY94.001

    (iii) For a rigid plastic IBC containing liquids, made from plastic 
with structural equipment withstanding the stack load and with a 
manufacturer's symbol in place of the manufacturer's name and address:
[GRAPHIC] [TIFF OMITTED] TR26JY94.002

    (iv) For a composite IBC containing liquids, with a rigid plastic 
inner receptacle and an outer steel body and with the symbol of a DOT 
approved third-party test laboratory:
[GRAPHIC] [TIFF OMITTED] TR26JY94.003

    (b) Additional marking. In addition to markings required in 
paragraph (a) of this section, each IBC must be marked as follows in a 
place near the markings required in paragraph (a) of this section that 
is readily accessible for inspection. Where units of measure are used, 
the metric unit indicated (e.g., 450 L) must also appear.
    (1) For each rigid plastic and composite IBC, the following markings 
must be included:
    (i) Rated capacity in L of water at 20 [deg]C (68 [deg]F);
    (ii) Tare mass in kilograms;

[[Page 226]]

    (iii) Gauge test pressure in kPa;
    (iv) Date of last leakproofness test, if applicable (month and 
year); and
    (v) Date of last inspection (month and year).
    (2) For each metal IBC, the following markings must be included on a 
metal corrosion-resistant plate:
    (i) Rated capacity in L of water at 20 [deg]C (68 [deg]F);
    (ii) Tare mass in kilograms;
    (iii) Date of last leakproofness test, if applicable (month and 
year);
    (iv) Date of last inspection (month and year);
    (v) Maximum loading/discharge pressure, in kPa, if applicable;
    (vi) Body material and its minimum thickness in mm; and
    (vii) Serial number assigned by the manufacturer.
    (3) Markings required by paragraph (b)(1) or (b)(2) of this section 
may be preceded by the narrative description of the marking, e.g. ``Tare 
Mass: * * *'' where the ``* * *'' are replaced with the tare mass in 
kilograms of the IBC.
    (4) For each fiberboard and wooden IBC, the tare mass in kg must be 
shown.
    (5) Each flexible IBC may be marked with a pictogram displaying 
recommended lifting methods.
    (6) For each composite IBC, the inner receptacle must be marked with 
at least the following information:
    (i) The code number designating the IBC design type, the name and 
address or symbol of the manufacturer, the date of manufacture and the 
country authorizing the allocation of the mark as specified in paragraph 
(a) of this section;
    (ii) When a composite IBC is designed in such a manner that the 
outer casing is intended to be dismantled for transport when empty (such 
as, for the return of the IBC for reuse to the original consignor), each 
of the parts intended to be detached when so dismantled must be marked 
with the month and year of manufacture and the name or symbol of the 
manufacturer.
    (7) The symbol applicable to an IBC designed for stacking or not 
designed for stacking, as appropriate, must be marked on all IBCs 
manufactured, repaired or remanufactured after January 1, 2011 as 
follows:
    (i)
    [GRAPHIC] [TIFF OMITTED] TR04JA10.097
    
    (ii) Display the symbol in a durable and visible manner.
    (iii) The symbol must not be less than 100 mm (3.9 inches) by 100 mm 
(3.9 inches).
    (iv) For IBCs designed for stacking, the maximum permitted stacking 
load applicable when the IBC is in use must be displayed with the 
symbol. The mass in kilograms (kg) marked above the symbol must not 
exceed the load imposed during the design test, as indicated by the 
marking in paragraph (a)(1)(vii) of this section, divided by 1.8. The 
letters and numbers indicating the mass must be at least 12 mm (0.48 
inches).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended by Amdt. 178-119, 
62 FR 24743, May 6, 1997; 64 FR 10782, Mar. 5, 1999; 65 FR 50462, Aug. 
18, 2000; 65 FR 58632, Sept. 29, 2000; 66 FR 33451, June 21, 2001; 66 FR 
45387, Aug. 28, 2001; 74 FR 2269, Jan. 14, 2009; 75 FR 74, Jan. 4, 2010; 
75 FR 5396, Feb. 2, 2010; 76 FR 3389, Jan.19, 2011]



Sec. 178.704  General IBC standards.

    (a) Each IBC must be resistant to, or protected from, deterioration 
due to exposure to the external environment.

[[Page 227]]

IBCs intended for solid hazardous materials must be sift-proof and 
water-resistant.
    (b) All service equipment must be so positioned or protected as to 
minimize potential loss of contents resulting from damage during IBC 
handling and transportation.
    (c) Each IBC, including attachments, and service and structural 
equipment, must be designed to withstand, without loss of hazardous 
materials, the internal pressure of the contents and the stresses of 
normal handling and transport. An IBC intended for stacking must be 
designed for stacking. Any lifting or securing features of an IBC must 
be of sufficient strength to withstand the normal conditions of handling 
and transportation without gross distortion or failure and must be 
positioned so as to cause no undue stress in any part of the IBC.
    (d) An IBC consisting of a packaging within a framework must be so 
constructed that:
    (1) The body is not damaged by the framework;
    (2) The body is retained within the framework at all times; and
    (3) The service and structural equipment are fixed in such a way 
that they cannot be damaged if the connections between body and frame 
allow relative expansion or motion.
    (e) Bottom discharge valves must be secured in the closed position 
and the discharge system suitably protected from damage. Valves having 
lever closures must be secured against accidental opening. The open or 
closed position of each valve must be readily apparent. For each IBC 
containing a liquid, a secondary means of sealing the discharge aperture 
must also be provided, e.g., by a blank flange or equivalent device.
    (f) IBC design types must be constructed in such a way as to be 
bottom-lifted or top-lifted as specified in Sec. Sec. 178.811 and 
178.812.

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001; 68 FR 61942, Oct. 30, 2003]



Sec. 178.705  Standards for metal IBCs.

    (a) The provisions in this section apply to metal IBCs intended to 
contain liquids and solids. Metal IBC types are designated:
    (1) 11A, 11B, 11N for solids that are loaded or discharged by 
gravity.
    (2) 21A, 21B, 21N for solids that are loaded or discharged at a 
gauge pressure greater than 10 kPa (1.45 psig).
    (3) 31A, 31B, 31N for liquids or solids.
    (b) Definitions for metal IBCs:
    (1) Metal IBC means an IBC with a metal body, together with 
appropriate service and structural equipment.
    (2) Protected means providing the IBC body with additional external 
protection against impact and abrasion. For example, a multi-layer 
(sandwich) or double wall construction or a frame with a metal lattice-
work casing.
    (c) Construction requirements for metal IBCs are as follows:
    (1) Body. The body must be made of ductile metal materials. Welds 
must be made so as to maintain design type integrity of the receptacle 
under conditions normally incident to transportation.
    (i) The use of dissimilar metals must not result in deterioration 
that could affect the integrity of the body.
    (ii) Aluminum IBCs intended to contain flammable liquids must have 
no movable parts, such as covers and closures, made of unprotected steel 
liable to rust, which might cause a dangerous reaction from friction or 
percussive contact with the aluminum.
    (iii) Metals used in fabricating the body of a metal IBC must meet 
the following requirements:
    (A) For steel, the percentage elongation at fracture must not be 
less than 10,000/Rm with a minimum of 20 percent; where Rm = minimum 
tensile strength of the steel to be used, in N/mm\2\; if U.S. Standard 
units of psi are used for tensile strength then the ratio becomes 10,000 
x (145/Rm).
    (B) For aluminum, the percentage elongation at fracture must not be 
less than 10,000/(6Rm) with an absolute minimum of eight percent; if 
U.S. Standard units of psi are used for tensile strength then the ratio 
becomes 10,000 x 145 / (6Rm).
    (C) Specimens used to determine the elongation at fracture must be 
taken transversely to the direction of rolling and be so secured that:

Lo = 5d


[[Page 228]]



or

Lo = 5.65 [radic]A

where:

Lo = gauge length of the specimen before the test
d = diameter
A = cross-sectional area of test specimen.

    (iv) Minimum wall thickness:
    (A) For a reference steel having a product of Rm x Ao = 10,000, 
where Ao is the minimum elongation (as a percentage) of the reference 
steel to be used on fracture under tensile stress (Rm x Ao = 10,000 x 
145; if tensile strength is in U.S. Standard units of pounds per square 
inch), the wall thickness must not be less than:

----------------------------------------------------------------------------------------------------------------
                                                             Wall thickness (T) in mm
                                --------------------------------------------------------------------------------
   Capacity (C) in liters \1\              Types 11A, 11B, 11N              Types 21A, 21B, 21N, 31A, 31B, 31N
                                --------------------------------------------------------------------------------
                                     Unprotected           Protected          Unprotected          Protected
----------------------------------------------------------------------------------------------------------------
C<=1000........................  2.0................  1.5...............  2.5...............  2.0
10001 = required equivalent wall thickness of the metal to be 
used (in mm or if eo is in inches, use formula for U.S. 
Standard units).
eo = required minimum wall thickness for the reference steel 
(in mm or if eo is in inches, use formula for U.S. Standard 
units).
Rm1 = guaranteed minimum tensile strength of the metal to be 
used (in N/mm\2\ or for U.S. Standard units, use psi).
A1 = minimum elongation (as a percentage) of the metal to be 
used on fracture under tensile stress (see paragraph (c)(1) of this 
section).

    (C) For purposes of the calculation described in paragraph 
(c)(1)(iv)(B) of this section, the guaranteed minimum tensile strength 
of the metal to be used (Rm1) must be the minimum value 
according to material standards. However, for austenitic (stainless) 
steels, the specified minimum value for Rm, according to the material 
standards, may be increased by up to 15% when a greater value is 
provided in the material inspection certificate. When no material 
standard exists for the material in question, the value of Rm must be 
the minimum value indicated in the material inspection certificate.
    (2) Pressure relief. The following pressure relief requirements 
apply to IBCs intended for liquids:
    (i) IBCs must be capable of releasing a sufficient amount of vapor 
in the event of fire engulfment to ensure that no rupture of the body 
will occur due to pressure build-up. This can be achieved by spring-
loaded or non-reclosing pressure relief devices or by other means of 
construction.
    (ii) The start-to-discharge pressure may not be higher than 65 kPa 
(9 psig) and no lower than the vapor pressure of the hazardous material 
plus the partial pressure of the air or other inert gases, measured in 
the IBC at 55 [deg]C (131 [deg]F), determined on the basis of a maximum 
degree of filling as specified in Sec. 173.35(d) of this subchapter. 
This does not apply to fusible devices unless such devices are the only 
source of pressure relief for the IBC. Pressure relief devices must be 
fitted in the vapor space.
    (d) Metal IBCs may not have a volumetric capacity greater than 3,000 
L

[[Page 229]]

(793 gallons) or less than 450 L (119 gallons).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended by Amdt. 178-108, 
60 FR 40038, Aug. 4, 1995; Amdt. 178-117, 61 FR 50629, Sept. 26, 1996; 
66 FR 33452, June 21, 2001; 66 FR 45386, 45387, Aug. 28, 2001; 68 FR 
45041, July 31, 2003; 75 FR 5396, Feb. 2, 2010]



Sec. 178.706  Standards for rigid plastic IBCs.

    (a) The provisions in this section apply to rigid plastic IBCs 
intended to contain solids or liquids. Rigid plastic IBC types are 
designated:
    (1) 11H1 fitted with structural equipment designed to withstand the 
whole load when IBCs are stacked, for solids which are loaded or 
discharged by gravity.
    (2) 11H2 freestanding, for solids which are loaded or discharged by 
gravity.
    (3) 21H1 fitted with structural equipment designed to withstand the 
whole load when IBCs are stacked, for solids which are loaded or 
discharged under pressure.
    (4) 21H2 freestanding, for solids which are loaded or discharged 
under pressure.
    (5) 31H1 fitted with structural equipment designed to withstand the 
whole load when IBCs are stacked, for liquids.
    (6) 31H2 freestanding, for liquids.
    (b) Rigid plastic IBCs consist of a rigid plastic body, which may 
have structural equipment, together with appropriate service equipment.
    (c) Rigid plastic IBCs must be manufactured from plastic material of 
known specifications and be of a strength relative to its capacity and 
to the service it is required to perform. In addition to conformance to 
Sec. 173.24 of this subchapter, plastic materials must be resistant to 
aging and to degradation caused by ultraviolet radiation.
    (1) If protection against ultraviolet radiation is necessary, it 
must be provided by the addition of a pigment or inhibiter such as 
carbon black. These additives must be compatible with the contents and 
remain effective throughout the life of the IBC body. Where use is made 
of carbon black, pigments or inhibitors, other than those used in the 
manufacture of the tested design type, retesting may be omitted if 
changes in the carbon black content, the pigment content or the 
inhibitor content do not adversely affect the physical properties of the 
material of construction.
    (2) Additives may be included in the composition of the plastic 
material to improve the resistance to aging or to serve other purposes, 
provided they do not adversely affect the physical or chemical 
properties of the material of construction.
    (3) No used material other than production residues or regrind from 
the same manufacturing process may be used in the manufacture of rigid 
plastic IBCs.
    (4) Rigid plastic IBCs intended for the transportation of liquids 
must be capable of releasing a sufficient amount of vapor to prevent the 
body of the IBC from rupturing if it is subjected to an internal 
pressure in excess of that for which it was hydraulically tested. This 
may be achieved by spring-loaded or non-reclosing pressure relief 
devices or by other means of construction.
    (d) Rigid plastic IBCs may not have a volumetric capacity greater 
than 3,000 L (793 gallons) or less than 450 L (119 gallons).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended at 66 FR 45386, 
45387, Aug. 28, 2001; 75 FR 5396, Feb. 2, 2010]



Sec. 178.707  Standards for composite IBCs.

    (a) The provisions in this section apply to composite IBCs intended 
to contain solids and liquids. To complete the marking codes listed 
below, the letter ``Z'' must be replaced by a capital letter in 
accordance with Sec. 178.702(a)(2) to indicate the material used for 
the outer packaging. Composite IBC types are designated:
    (1) 11HZ1 Composite IBCs with a rigid plastic inner receptacle for 
solids loaded or discharged by gravity.
    (2) 11HZ2 Composite IBCs with a flexible plastic inner receptacle 
for solids loaded or discharged by gravity.
    (3) 21HZ1 Composite IBCs with a rigid plastic inner receptacle for 
solids loaded or discharged under pressure.
    (4) 21HZ2 Composite IBCs with a flexible plastic inner receptacle 
for solids loaded or discharged under pressure.
    (5) 31HZ1 Composite IBCs with a rigid plastic inner receptacle for 
liquids.

[[Page 230]]

    (6) 31HZ2 Composite IBCs with a flexible plastic inner receptacle 
for liquids.
    (b) Definitions for composite IBC types:
    (1) A composite IBC is an IBC which consists of a rigid outer 
packaging enclosing a plastic inner receptacle together with any service 
or other structural equipment. The outer packaging of a composite IBC is 
designed to bear the entire stacking load. The inner receptacle and 
outer packaging form an integral packaging and are filled, stored, 
transported, and emptied as a unit.
    (2) The term plastic means polymeric materials (i.e., plastic or 
rubber).
    (3) A ``rigid'' inner receptacle is an inner receptacle which 
retains its general shape when empty without closures in place and 
without benefit of the outer casing. Any inner receptacle that is not 
``rigid'' is considered to be ``flexible.''
    (c) Construction requirements for composite IBCs with plastic inner 
receptacles are as follows:
    (1) The outer packaging must consist of rigid material formed so as 
to protect the inner receptacle from physical damage during handling and 
transportation, but is not required to perform the secondary containment 
function. It includes the base pallet where appropriate. The inner 
receptacle is not intended to perform a containment function without the 
outer packaging.
    (2) A composite IBC with a fully enclosing outer packaging must be 
designed to permit assessment of the integrity of the inner container 
following the leakproofness and hydraulic tests. The outer packaging of 
31HZ2 composite IBCs must enclose the inner receptacles on all sides.
    (3) The inner receptacle must be manufactured from plastic material 
of known specifications and be of a strength relative to its capacity 
and to the service it is required to perform. In addition to conformance 
with the requirements of Sec. 173.24 of this subchapter, the material 
must be resistant to aging and to degradation caused by ultraviolet 
radiation. The inner receptacle of 31HZ2 composite IBCs must consist of 
at least three plies of film.
    (i) If necessary, protection against ultraviolet radiation must be 
provided by the addition of pigments or inhibitors such as carbon black. 
These additives must be compatible with the contents and remain 
effective throughout the life of the inner receptacle. Where use is made 
of carbon black, pigments, or inhibitors, other than those used in the 
manufacture of the tested design type, retesting may be omitted if the 
carbon black content, the pigment content, or the inhibitor content do 
not adversely affect the physical properties of the material of 
construction.
    (ii) Additives may be included in the composition of the plastic 
material of the inner receptacle to improve resistance to aging, 
provided they do not adversely affect the physical or chemical 
properties of the material.
    (iii) No used material other than production residues or regrind 
from the same manufacturing process may be used in the manufacture of 
inner receptacles.
    (iv) Composite IBCs intended for the transportation of liquids must 
be capable of releasing a sufficient amount of vapor to prevent the body 
of the IBC from rupturing if it is subjected to an internal pressure in 
excess of that for which it was hydraulically tested. This may be 
achieved by spring-loaded or non-reclosing pressure relief devices or by 
other means of construction.
    (4) The strength of the construction material comprising the outer 
packaging and the manner of construction must be appropriate to the 
capacity of the composite IBC and its intended use. The outer packaging 
must be free of any projection that might damage the inner receptacle.
    (i) Outer packagings of natural wood must be constructed of well 
seasoned wood that is commercially dry and free from defects that would 
materially lessen the strength of any part of the outer packaging. The 
tops and bottoms may be made of water-resistant reconstituted wood such 
as hardboard or particle board. Materials other than natural wood may be 
used for construction of structural equipment of the outer packaging.
    (ii) Outer packagings of plywood must be made of well-seasoned, 
rotary

[[Page 231]]

cut, sliced, or sawn veneer, commercially dry and free from defects that 
would materially lessen the strength of the casing. All adjacent plies 
must be glued with water-resistant adhesive. Materials other than 
plywood may be used for construction of structural equipment of the 
outer packaging. Outer packagings must be firmly nailed or secured to 
corner posts or ends or be assembled by equally suitable devices.
    (iii) Outer packagings of reconstituted wood must be constructed of 
water-resistant reconstituted wood such as hardboard or particle board. 
Materials other than reconstituted wood may be used for the construction 
of structural equipment of reconstituted wood outer packaging.
    (iv) Fiberboard outer packagings must be constructed of strong, 
solid, or double-faced corrugated fiberboard (single or multiwall).
    (A) Water resistance of the outer surface must be such that the 
increase in mass, as determined in a test carried out over a period of 
30 minutes by the Cobb method of determining water absorption, is not 
greater than 155 grams per square meter (0.0316 pounds per square 
foot)--see ISO 535 (E) (IBR, see Sec. 171.7 of this subchapter). 
Fiberboard must have proper bending qualities. Fiberboard must be cut, 
creased without cutting through any thickness of fiberboard, and slotted 
so as to permit assembly without cracking, surface breaks, or undue 
bending. The fluting of corrugated fiberboard must be firmly glued to 
the facings.
    (B) The ends of fiberboard outer packagings may have a wooden frame 
or be constructed entirely of wood. Wooden battens may be used for 
reinforcements.
    (C) Manufacturers' joints in the bodies of outer packagings must be 
taped, lapped and glued, or lapped and stitched with metal staples.
    (D) Lapped joints must have an appropriate overlap.
    (E) Where closing is effected by gluing or taping, a water-resistant 
adhesive must be used.
    (F) All closures must be sift-proof.
    (v) Outer packagings of plastic materials must be constructed in 
accordance with the relevant provisions of paragraph (c)(3) of this 
section.
    (5) Any integral pallet base forming part of an IBC, or any 
detachable pallet, must be suitable for the mechanical handling of an 
IBC filled to its maximum permissible gross mass.
    (i) The pallet or integral base must be designed to avoid 
protrusions that may cause damage to the IBC in handling.
    (ii) The outer packaging must be secured to any detachable pallet to 
ensure stability in handling and transportation. Where a detachable 
pallet is used, its top surface must be free from sharp protrusions that 
might damage the IBC.
    (iii) Strengthening devices, such as timber supports to increase 
stacking performance, may be used but must be external to the inner 
receptacle.
    (iv) The load-bearing surfaces of IBCs intended for stacking must be 
designed to distribute loads in a stable manner. An IBC intended for 
stacking must be designed so that loads are not supported by the inner 
receptacle.
    (6) Intermediate IBCs of type 31HZ2 must be limited to a capacity of 
not more than 1,250 L.
    (d) Composite IBCs may not have a volumetric capacity greater than 
3,000 L (793 gallons) or less than 450 L (119 gallons).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended by Amdt. 178-119, 
62 FR 24743, May 6, 1997; 66 FR 45387, Aug. 28, 2001; 67 FR 61016, Sept. 
27, 2002; 68 FR 75758, Dec. 31, 2003; 69 FR 54046, Sept. 7, 2004; 75 FR 
5396, Feb. 2, 2010]



Sec. 178.708  Standards for fiberboard IBCs.

    (a) The provisions of this section apply to fiberboard IBCs intended 
to contain solids that are loaded or discharged by gravity. Fiberboard 
IBCs are designated: 11G.
    (b) Definitions for fiberboard IBC types:
    (1) Fiberboard IBCs consist of a fiberboard body with or without 
separate top and bottom caps, appropriate service and structural 
equipment, and if necessary an inner liner (but no inner packaging).

[[Page 232]]

    (2) Liner means a separate tube or bag, including the closures of 
its openings, inserted in the body but not forming an integral part of 
it.
    (c) Construction requirements for fiberboard IBCs are as follows:
    (1) Top lifting devices are prohibited in fiberboard IBCs.
    (2) Fiberboard IBCs must be constructed of strong, solid or double-
faced corrugated fiberboard (single or multiwall) that is appropriate to 
the capacity of the outer packaging and its intended use. Water 
resistance of the outer surface must be such that the increase in mass, 
as determined in a test carried out over a period of 30 minutes by the 
Cobb method of determining water absorption, is not greater than 155 
grams per square meter (0.0316 pounds per square foot)--see ISO 535 (E) 
(IBR, see Sec. 171.7 of this subchapter). Fiberboard must have proper 
bending qualities. Fiberboard must be cut, creased without cutting 
through any thickness of fiberboard, and slotted so as to permit 
assembly without cracking, surface breaks, or undue bending. The fluting 
of corrugated fiberboard must be firmly glued to the facings.
    (i) The walls, including top and bottom, must have a minimum 
puncture resistance of 15 Joules (11 foot-pounds of energy) measured 
according to ISO 3036 (IBR, see Sec. 171.7 of this subchapter).
    (ii) Manufacturers' joints in the bodies of IBCs must be made with 
an appropriate overlap and be taped, glued, stitched with metal staples 
or fastened by other means at least equally effective. Where joints are 
made by gluing or taping, a water-resistant adhesive must be used. Metal 
staples must pass completely through all pieces to be fastened and be 
formed or protected so that any inner liner cannot be abraded or 
punctured by them.
    (3) The strength of the material used and the construction of the 
liner must be appropriate to the capacity of the IBC and the intended 
use. Joints and closures must be sift-proof and capable of withstanding 
pressures and impacts liable to occur under normal conditions of 
handling and transport.
    (4) Any integral pallet base forming part of an IBC, or any 
detachable pallet, must be suitable for the mechanical handling of an 
IBC filled to its maximum permissible gross mass.
    (i) The pallet or integral base must be designed to avoid 
protrusions that may cause damage to the IBC in handling.
    (ii) The outer packaging must be secured to any detachable pallet to 
ensure stability in handling and transport. Where a detachable pallet is 
used, its top surface must be free from sharp protrusions that might 
damage the IBC.
    (iii) Strengthening devices, such as timber supports to increase 
stacking performance, may be used but must be external to the inner 
liner.
    (iv) The load-bearing surfaces of IBCs intended for stacking must be 
designed to distribute loads in a stable manner.
    (d) Fiberboard IBCs may not have a volumetric capacity greater than 
3,000 L (793 gallons) or less than 450 L (119 gallons).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001; 68 FR 75758, Dec. 31, 2003; 75 FR 5396, Feb. 2, 2010]



Sec. 178.709  Standards for wooden IBCs.

    (a) The provisions in this section apply to wooden IBCs intended to 
contain solids that are loaded or discharged by gravity. Wooden IBC 
types are designated:
    (1) 11C Natural wood with inner liner.
    (2) 11D Plywood with inner liner.
    (3) 11F Reconstituted wood with inner liner.
    (b) Definitions for wooden IBCs:
    (1) Wooden IBCs consist of a rigid or collapsible wooden body 
together with an inner liner (but no inner packaging) and appropriate 
service and structural equipment.
    (2) Liner means a separate tube or bag, including the closures of 
its openings, inserted in the body but not forming an integral part of 
it.
    (c) Construction requirements for wooden IBCs are as follows:
    (1) Top lifting devices are prohibited in wooden IBCs.
    (2) The strength of the materials used and the method of 
construction must be appropriate to the capacity and intended use of the 
IBC.
    (i) Natural wood used in the construction of an IBC must be well-
seasoned, commercially dry, and free from

[[Page 233]]

defects that would materially lessen the strength of any part of the 
IBC. Each IBC part must consist of uncut wood or a piece equivalent in 
strength and integrity. IBC parts are equivalent to one piece when a 
suitable method of glued assembly is used (i.e., a Lindermann joint, 
tongue and groove joint, ship lap or rabbet joint, or butt joint with at 
least two corrugated metal fasteners at each joint, or when other 
methods at least equally effective are used). Materials other than 
natural wood may be used for the construction of structural equipment of 
the outer packaging.
    (ii) Plywood used in construction of bodies must be at least 3-ply. 
Plywood must be made of well-seasoned, rotary-cut, sliced or sawn 
veneer, commercially dry, and free from defects that would materially 
lessen the strength of the body. All adjacent plies must be glued with 
water-resistant adhesive. Materials other than plywood may be used for 
the construction of structural equipment of the outer packaging.
    (iii) Reconstituted wood used in construction of bodies must be 
water resistant reconstituted wood such as hardboard or particle board. 
Materials other than reconstituted wood may be used for the construction 
of structural equipment of the outer packaging.
    (iv) Wooden IBCs must be firmly nailed or secured to corner posts or 
ends or be assembled by similar devices.
    (3) The strength of the material used and the construction of the 
liner must be appropriate to the capacity of the IBC and its intended 
use. Joints and closures must be sift-proof and capable of withstanding 
pressures and impacts liable to occur under normal conditions of 
handling and transportation.
    (4) Any integral pallet base forming part of an IBC, or any 
detachable pallet, must be suitable for the mechanical handling of an 
IBC filled to its maximum permissible gross mass.
    (i) The pallet or integral base must be designed to avoid 
protrusions that may cause damage to the IBC in handling.
    (ii) The outer packaging must be secured to any detachable pallet to 
ensure stability in handling and transportation. Where a detachable 
pallet is used, its top surface must be free from sharp protrusions that 
might damage the IBC.
    (iii) Strengthening devices, such as timber supports to increase 
stacking performance, may be used but must be external to the inner 
liner.
    (iv) The load-bearing surfaces of IBCs intended for stacking must be 
designed to distribute loads in a stable manner.
    (d) Wooden IBCs may not have a volumetric capacity greater than 
3,000 L (793 gallons) or less than 450 L (119 gallons).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001; 75 FR 5397, Feb. 2, 2010]



Sec. 178.710  Standards for flexible IBCs.

    (a) The provisions of this section apply to flexible IBCs intended 
to contain solid hazardous materials. Flexible IBC types are designated:
    (1) 13H1 woven plastic without coating or liner.
    (2) 13H2 woven plastic, coated.
    (3) 13H3 woven plastic with liner.
    (4) 13H4 woven plastic, coated and with liner.
    (5) 13H5 plastic film.
    (6) 13L1 textile without coating or liner.
    (7) 13L2 textile, coated.
    (8) 13L3 textile with liner.
    (9) 13L4 textile, coated and with liner.
    (10) 13M1 paper, multiwall.
    (11) 13M2 paper, multiwall, water resistant.
    (b) Definitions for flexible IBCs:
    (1) Flexible IBCs consist of a body constructed of film, woven 
plastic, woven fabric, paper, or combination thereof, together with any 
appropriate service equipment and handling devices, and if necessary, an 
inner coating or liner.
    (2) Woven plastic means a material made from stretched tapes or 
monofilaments.
    (3) Handling device means any sling, loop, eye, or frame attached to 
the body of the IBC or formed from a continuation of the IBC body 
material.
    (c) Construction requirements for flexible IBCs are as follows:
    (1) The strength of the material and the construction of the 
flexible IBC must be appropriate to its capacity and its intended use.

[[Page 234]]

    (2) All materials used in the construction of flexible IBCs of types 
13M1 and 13M2 must, after complete immersion in water for not less than 
24 hours, retain at least 85 percent of the tensile strength as measured 
originally on the material conditioned to equilibrium at 67 percent 
relative humidity or less.
    (3) Seams must be stitched or formed by heat sealing, gluing or any 
equivalent method. All stitched seam-ends must be secured.
    (4) In addition to conformance with the requirements of Sec. 173.24 
of this subchapter, flexible IBCs must be resistant to aging and 
degradation caused by ultraviolet radiation.
    (5) For plastic flexible IBCs, if necessary, protection against 
ultraviolet radiation must be provided by the addition of pigments or 
inhibitors such as carbon black. These additives must be compatible with 
the contents and remain effective throughout the life of the container. 
Where use is made of carbon black, pigments, or inhibitors, other than 
those used in the manufacture of the tested design type, retesting may 
be omitted if the carbon black content, the pigment content or the 
inhibitor content does not adversely affect the physical properties of 
the material of construction. Additives may be included in the 
composition of the plastic material to improve resistance to aging, 
provided they do not adversely affect the physical or chemical 
properties of the material.
    (6) No used material other than production residues or regrind from 
the same manufacturing process may be used in the manufacture of plastic 
flexible IBCs. This does not preclude the re-use of component parts such 
as fittings and pallet bases, provided such components have not in any 
way been damaged in previous use.
    (7) When flexible IBCs are filled, the ratio of height to width may 
not be more than 2:1.
    (d) Flexible IBCs: (1) May not have a volumetric capacity greater 
than 3,000 L (793 gallons) or less than 56 L (15 gallons); and
    (2) Must be designed and tested to a capacity of no less than 50 kg 
(110 pounds).

[Amdt. 178-103, 59 FR 38068, July 26, 1994, as amended by Amdt. 178-108, 
60 FR 40038, Aug. 4, 1995; 66 FR 45386, Aug. 28, 2001; 75 FR 5397, Feb. 
2, 2010]



                        Subpart O_Testing of IBCs



Sec. 178.800  Purpose and scope.

    This subpart prescribes certain testing requirements for IBCs 
identified in subpart N of this part.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended by 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.801  General requirements.

    (a) General. The test procedures prescribed in this subpart are 
intended to ensure that IBCs containing hazardous materials can 
withstand normal conditions of transportation and are considered minimum 
requirements. Each packaging must be manufactured and assembled so as to 
be capable of successfully passing the prescribed tests and of 
conforming to the requirements of Sec. 173.24 of this subchapter at all 
times while in transportation.
    (b) Responsibility. It is the responsibility of the IBC manufacturer 
to assure that each IBC is capable of passing the prescribed tests. To 
the extent that an IBC assembly function, including final closure, is 
performed by the person who offers a hazardous material for 
transportation, that person is responsible for performing the function 
in accordance with Sec. Sec. 173.22 and 178.2 of this subchapter.
    (c) Definitions. For the purpose of this subpart:
    (1) IBC design type refers to an IBC that does not differ in 
structural design, size, material of construction, wall thickness, 
manner of construction and representative service equipment.
    (2) Design qualification testing is the performance of the drop, 
leakproofness, hydrostatic pressure, stacking, bottom-lift or top-lift, 
tear, topple, righting and vibration tests, as applicable, prescribed in 
this subpart, for each different IBC design type, at the start of 
production of that packaging.
    (3) Periodic design requalification test is the performance of the 
applicable tests

[[Page 235]]

specified in paragraph (c)(2) of this section on an IBC design type, in 
order to requalify the design for continued production at the frequency 
specified in paragraph (e) of this section.
    (4) Production inspection is the inspection that must initially be 
conducted on each newly manufactured IBC.
    (5) Production testing is the performance of the leakproofness test 
in accordance with paragraph (f) of this section on each IBC intended to 
contain solids discharged by pressure or intended to contain liquids.
    (6) Periodic retest and inspection is performance of the applicable 
test and inspections on each IBC at the frequency specified in Sec. 
180.352 of this subchapter.
    (7) Different IBC design type is one that differs from a previously 
qualified IBC design type in structural design, size, material of 
construction, wall thickness, or manner of construction, but does not 
include:
    (i) A packaging which differs in surface treatment;
    (ii) A rigid plastic IBC or composite IBC which differs with regard 
to additives used to comply with Sec. Sec. 178.706(c), 178.707(c) or 
178.710(c);
    (iii) A packaging which differs only in its lesser external 
dimensions (i.e., height, width, length) provided materials of 
construction and material thicknesses or fabric weight remain the same;
    (iv) A packaging which differs in service equipment.
    (d) Design qualification testing. The packaging manufacturer shall 
achieve successful test results for the design qualification testing at 
the start of production of each new or different IBC design type. The 
service equipment selected for this design qualification testing shall 
be representative of the type of service equipment that will be fitted 
to any finished IBC body under the design. Application of the 
certification mark by the manufacturer shall constitute certification 
that the IBC design type passed the prescribed tests in this subpart.
    (e) Periodic design requalification testing. (1) Periodic design 
requalification must be conducted on each qualified IBC design type if 
the manufacturer is to maintain authorization for continued production. 
The IBC manufacturer shall achieve successful test results for the 
periodic design requalification at sufficient frequency to ensure each 
packaging produced by the manufacturer is capable of passing the design 
qualification tests. Design requalification tests must be conducted at 
least once every 12 months.
    (2) Changes in the frequency of design requalification testing 
specified in paragraph (e)(1) of this section are authorized if approved 
by the Associate Administrator. These requests must be based on:
    (i) Detailed quality assurance programs that assure that proposed 
decreases in test frequency maintain the integrity of originally tested 
IBC design types; and
    (ii) Demonstrations that each IBC produced is capable of 
withstanding higher standards (e.g., increased drop height, hydrostatic 
pressure, wall thickness, fabric weight).
    (f) Production testing and inspection. (1) Production testing 
consists of the leakproofness test prescribed in Sec. 178.813 of this 
subpart and must be performed on each IBC intended to contain solids 
discharged by pressure or intended to contain liquids. For this test:
    (i) The IBC need not have its closures fitted, except that the IBC 
must be fitted with its primary bottom closure.
    (ii) The inner receptacle of a composite IBC may be tested without 
the outer IBC body, provided the test results are not affected.
    (2) Applicable inspection requirements in Sec. 180.352 of this 
subchapter must be performed on each IBC initially after production.
    (g) Test samples. The IBC manufacturer shall conduct the design 
qualification and periodic design requalification tests prescribed in 
this subpart using random samples of IBCs, according to the appropriate 
test section.
    (h) Selective testing of IBCs. Variation of a tested IBC design type 
is permitted without further testing, provided selective testing 
demonstrates an equivalent or greater level of safety than the design 
type tested and which has been approved by the Associate Administrator.
    (i) Approval of equivalent packagings. An IBC differing from the 
standards in

[[Page 236]]

subpart N of this part, or tested using methods other than those 
specified in this subpart, may be used if approved by the Associate 
Administrator. Such IBCs must be shown to be equally effective, and 
testing methods used must be equivalent.
    (j) Proof of compliance. Notwithstanding the periodic design 
requalification testing intervals specified in paragraph (e) of this 
section, the Associate Administrator, or a designated representative, 
may at any time require demonstration of compliance by a manufacturer, 
through testing in accordance with this subpart, that packagings meet 
the requirements of this subpart. As required by the Associate 
Administrator, or a designated representative, the manufacturer shall 
either:
    (1) Conduct performance tests or have tests conducted by an 
independent testing facility, in accordance with this subpart; or
    (2) Make a sample IBC available to the Associate Administrator, or a 
designated representative, for testing in accordance with this subpart.
    (k) Coatings. If an inner treatment or coating of an IBC is required 
for safety reasons, the manufacturer shall design the IBC so that the 
treatment or coating retains its protective properties even after 
withstanding the tests prescribed by this subpart.
    (l) Record retention. (1) The person who certifies an IBC design 
type shall keep records of design qualification tests for each IBC 
design type and for each periodic design requalification as specified in 
this part. These records must be maintained at each location where the 
IBC is manufactured and at each location where design qualification and 
periodic design requalification testing is performed. These records must 
be maintained for as long as IBCs are manufactured in accordance with 
each qualified design type and for at least 2.5 years thereafter. These 
records must include the following information: name and address of test 
facility; name and address of the person certifying the IBC; a unique 
test report identification; date of test report; manufacturer of the 
IBC; description of the IBC design type (e.g., dimensions, materials, 
closures, thickness, representative service equipment, etc.); maximum 
IBC capacity; characteristics of test contents; test descriptions and 
results (including drop heights, hydrostatic pressures, tear propagation 
length, etc.). Each test report must be signed with the name of the 
person conducting the test, and name of the person responsible for 
testing.
    (2) The person who certifies each IBC must make all records of 
design qualification tests and periodic design requalification tests 
available for inspection by a representative of the Department upon 
request.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended by Amdt. 178-108, 
60 FR 40038, Aug. 4, 1995; 66 FR 45386, Aug. 28, 2001; 66 FR 33452, June 
21, 2001; 68 FR 75758, Dec. 31, 2003; 73 FR 57008, Oct. 1, 2008; 74 FR 
2269, Jan. 14, 2009; 75 FR 5397, Feb. 2, 2010]



Sec. 178.802  Preparation of fiberboard IBCs for testing.

    (a) Fiberboard IBCs and composite IBCs with fiberboard outer 
packagings must be conditioned for at least 24 hours in an atmosphere 
maintained:
    (1) At 50 percent 2 percent relative humidity, 
and at a temperature of 23[deg] 2 [deg]C (73 
[deg]F 4 [deg]F); or
    (2) At 65 percent 2 percent relative humidity, 
and at a temperature of 20[deg] 2 [deg]C (68 
[deg]F 4 [deg]F), or 27 [deg]C 2 [deg]C (81 [deg]F 4 [deg]F).
    (b) Average values for temperature and humidity must fall within the 
limits in paragraph (a) of this section. Short-term fluctuations and 
measurement limitations may cause individual measurements to vary by up 
to 5 percent relative humidity without significant 
impairment of test reproducibility.
    (c) For purposes of periodic design requalification only, fiberboard 
IBCs or composite IBCs with fiberboard outer packagings may be at 
ambient conditions.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.803  Testing and certification of IBCs.

    Tests required for the certification of each IBC design type are 
specified in the following table. The letter X indicates that one IBC 
(except where

[[Page 237]]

noted) of each design type must be subjected to the tests in the order 
presented:

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                          IBC type
         Performance test         ----------------------------------------------------------------------------------------------------------------------
                                       Metal IBCs      Rigid plastic IBCs    Composite IBCs     Fiber-board IBCs       Wooden IBCs       Flexible IBCs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibration........................  \6\ X               \6\ X               \6\ X               \6\ X               \6\ X               \1.5\ X
Bottom lift......................  \2\ X               X                   X                   X                   X                   .................
Top lift.........................  \2\ X               \2\ X               \2\ X               ..................  ..................  \2,5\ X
Stacking.........................  \7\ X               \7\ X               \7\ X               \7\ X               \7\ X               \5\ X
Leakproofness....................  \3\ X               \3\ X               \3\ X               ..................  ..................  .................
Hydrostatic......................  \3\ X               \3\ X               \3\ X               ..................  ..................  .................
Drop.............................  \4\ X               \4\ X               \4\ X               \4\ X               \4\ X               \5\ X
Topple...........................  ..................  ..................  ..................  ..................  ..................  \5\ X
Righting.........................  ..................  ..................  ..................  ..................  ..................  \2,5\ X
Tear.............................  ..................  ..................  ..................  ..................  ..................  \5\ X
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Flexible IBCs must be capable of withstanding the vibration test.
\2\ This test must be performed only if IBCs are designed to be handled this way. For metal IBCs, at least one of the bottom lift or top lift tests must
  be performed.
\3\ The leakproofness and hydrostatic pressure tests are required only for IBCs intended to contain liquids or intended to contain solids loaded or
  discharged under pressure.
\4\ Another IBC of the same design type may be used for the drop test set forth in Sec. 178.810 of this subchapter.
\5\ Another different flexible IBC of the same design type may be used for each test.
\6\ The vibration test may be performed in another order for IBCs manufactured and tested under provisions of an exemption before October 1, 1994 and
  for non-DOT specification portable tanks tested before October 1, 1994, intended for export.
\7\ This test must be performed only if the IBC is designed to be stacked.


[Amdt. 178-108, 60 FR 40039, Aug. 4, 1995, as amended at 64 FR 51919, 
Sept. 27, 1999; 66 FR 45386, 45390, Aug. 28, 2001]



Sec. 178.810  Drop test.

    (a) General. The drop test must be conducted for the qualification 
of all IBC design types and performed periodically as specified in Sec. 
178.801(e) of this subpart.
    (b) Special preparation for the drop test. (1) Metal, rigid plastic, 
and composite IBCs intended to contain solids must be filled to not less 
than 95 percent of their maximum capacity, or if intended to contain 
liquids, to not less than 98 percent of their maximum capacity. Pressure 
relief devices must be removed and their apertures plugged or rendered 
inoperative.
    (2) Fiberboard and wooden IBCs must be filled with a solid material 
to not less than 95 percent of their maximum capacity; the contents must 
be evenly distributed.
    (3) Flexible IBCs must be filled to the maximum permissible gross 
mass; the contents must be evenly distributed.
    (4) Rigid plastic IBCs and composite IBCs with plastic inner 
receptacles must be conditioned for testing by reducing the temperature 
of the packaging and its contents to -18 [deg]C (0 [deg]F) or lower. 
Test liquids must be kept in the liquid state, if necessary, by the 
addition of anti-freeze. Water/anti-freeze solutions with a minimum 
specific gravity of 0.95 for testing at -18 [deg]C (0 [deg]F) or lower 
are considered acceptable test liquids, and may be considered equivalent 
to water for test purposes. IBCs conditioned in this way are not 
required to be conditioned in accordance with Sec. 178.802.
    (c) Test method. (1) Samples of all IBC design types must be dropped 
onto a rigid, non-resilient, smooth, flat and horizontal surface. The 
point of impact must be the most vulnerable part of the base of the IBC 
being tested. Following the drop, the IBC must be restored to the 
upright position for observation.
    (2) IBC design types with a capacity of 0.45 cubic meters (15.9 
cubic feet) or less must be subject to an additional drop test.
    (d) Drop height. (1) For all IBCs, drop heights are specified as 
follows:
    (i) Packing Group I: 1.8 m (5.9 feet).
    (ii) Packing Group II: 1.2 m (3.9 feet).
    (iii) Packing Group III: 0.8 m (2.6 feet).
    (2) Drop tests are to be performed with the solid or liquid to be 
transported or with a non-hazardous material having essentially the same 
physical characteristics.

[[Page 238]]

    (3) The specific gravity and viscosity of a substituted non-
hazardous material used in the drop test for liquids must be similar to 
the hazardous material intended for transportation. Water also may be 
used for the liquid drop test under the following conditions:
    (i) Where the substances to be carried have a specific gravity not 
exceeding 1.2, the drop heights must be those specified in paragraph 
(d)(1) of this section for each IBC design type; and
    (ii) Where the substances to be carried have a specific gravity 
exceeding 1.2, the drop heights must be as follows:
    (A) Packing Group I: SG x 1.5 m (4.9 feet).
    (B) Packing Group II: SG x 1.0 m (3.3 feet).
    (C) Packing Group III: SG x 0.67 m (2.2 feet).
    (e) Criteria for passing the test. For all IBC design types, there 
may be no damage which renders the IBC unsafe to be transported for 
salvage or for disposable, and no loss of contents. The IBC shall be 
capable of being lifted by an appropriate means until clear of the floor 
for five minutes. A slight discharge from a closure upon impact is not 
considered to be a failure of the IBC provided that no further leakage 
occurs. A slight discharge (e.g., from closures or stitch holes) upon 
impact is not considered a failure of the flexible IBC provided that no 
further leakage occurs after the IBC has been raised clear of the 
ground.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001; 69 FR 76186, Dec. 20, 2004; 71 FR 78635, Dec. 29, 2006; 
74 FR 2269, Jan. 14, 2009; 75 FR 5397, Feb. 2, 2010]



Sec. 178.811  Bottom lift test.

    (a) General. The bottom lift test must be conducted for the 
qualification of all IBC design types designed to be lifted from the 
base.
    (b) Special preparation for the bottom lift test. The IBC must be 
loaded to 1.25 times its maximum permissible gross mass, the load being 
evenly distributed.
    (c) Test method. All IBC design types must be raised and lowered 
twice by a lift truck with the forks centrally positioned and spaced at 
three quarters of the dimension of the side of entry (unless the points 
of entry are fixed). The forks must penetrate to three quarters of the 
direction of entry. The test must be repeated from each possible 
direction of entry.
    (d) Criteria for passing the test. For all IBC design types designed 
to be lifted from the base, there may be no permanent deformation which 
renders the IBC unsafe for transportation and no loss of contents.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.812  Top lift test.

    (a) General. The top lift test must be conducted for the 
qualification of all IBC design types designed to be lifted from the top 
or, for flexible IBCs, from the side.
    (b) Special preparation for the top lift test. (1) Metal, rigid 
plastic, and composite IBC design types must be loaded to twice the 
maximum permissible gross mass with the load being evenly distributed.
    (2) Flexible IBC design types must be filled to six times the 
maximum net mass, the load being evenly distributed.
    (c) Test method. (1) A metal or flexible IBC must be lifted in the 
manner for which it is designed until clear of the floor and maintained 
in that position for a period of five minutes.
    (2) Rigid plastic and composite IBC design types must be:
    (i) Lifted by each pair of diagonally opposite lifting devices, so 
that the hoisting forces are applied vertically, for a period of five 
minutes; and
    (ii) Lifted by each pair of diagonally opposite lifting devices, so 
that the hoisting forces are applied towards the center at 45[deg] to 
the vertical, for a period of five minutes.
    (3) If not tested as indicated in paragraph (c)(1) of this section, 
a flexible IBC design type must be tested as follows:
    (i) Fill the flexible IBC to 95% full with a material representative 
of the product to be shipped.
    (ii) Suspend the flexible IBC by its lifting devices.
    (iii) Apply a constant downward force through a specially designed 
platen. The platen will be a minimum of 60%

[[Page 239]]

and a maximum of 80% of the cross sectional surface area of the flexible 
IBC.
    (iv) The combination of the mass of the filled flexible IBC and the 
force applied through the platen must be a minimum of six times the 
maximum net mass of the flexible IBC. The test must be conducted for a 
period of five minutes.
    (v) Other equally effective methods of top lift testing and 
preparation may be used with approval of the Associate Administrator.
    (d) Criteria for passing the test. For all IBC design types designed 
to be lifted from the top, there may be no permanent deformation which 
renders the IBC, including the base pallets when applicable, unsafe for 
transportation, and no loss of contents.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 33452, 
June 21, 2001; 66 FR 45386, Aug. 28, 2001; 68 FR 45042, July 31, 2003]



Sec. 178.813  Leakproofness test.

    (a) General. The leakproofness test must be conducted for the 
qualification of all IBC design types and on all production units 
intended to contain solids that are loaded or discharged under pressure 
or intended to contain liquids.
    (b) Special preparation for the leakproofness test. Vented closures 
must either be replaced by similar non-vented closures or the vent must 
be sealed. For metal IBC design types, the initial test must be carried 
out before the fitting of any thermal insulation equipment. The inner 
receptacle of a composite IBC may be tested without the outer packaging 
provided the test results are not affected.
    (c) Test method and pressure applied. The leakproofness test must be 
carried out for a suitable length of time using air at a gauge pressure 
of not less than 20 kPa (2.9 psig). Leakproofness of IBC design types 
must be determined by coating the seams and joints with a heavy oil, a 
soap solution and water, or other methods suitable for the purpose of 
detecting leaks. Other methods, if at least equally effective, may be 
used in accordance with appendix B of this part, or if approved by the 
Associate Administrator, as provided in Sec. 178.801(i)).
    (d) Criterion for passing the test. For all IBC design types 
intended to contain solids that are loaded or discharged under pressure 
or intended to contain liquids, there may be no leakage of air from the 
IBC.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 64 FR 10782, 
Mar. 5, 1999; 66 FR 45185, 45386, Aug. 28, 2001]



Sec. 178.814  Hydrostatic pressure test.

    (a) General. The hydrostatic pressure test must be conducted for the 
qualification of all metal, rigid plastic, and composite IBC design 
types intended to contain solids that are loaded or discharged under 
pressure or intended to contain liquids.
    (b) Special preparation for the hydrostatic pressure test. For metal 
IBCs, the test must be carried out before the fitting of any thermal 
insulation equipment. For all IBCs, pressure relief devices and vented 
closures must be removed and their apertures plugged or rendered 
inoperative.
    (c) Test method. Hydrostatic gauge pressure must be measured at the 
top of the IBC. The test must be carried out for a period of at least 10 
minutes applying a hydrostatic gauge pressure not less than that 
indicated in paragraph (d) of this section. The IBCs may not be 
mechanically restrained during the test.
    (d) Hydrostatic gauge pressure applied. (1) For metal IBC design 
types, 31A, 31B, 31N: 65 kPa gauge pressure (9.4 psig).
    (2) For metal IBC design types 21A, 21B, 21N, 31A, 31B, 31N: 200 kPa 
(29 psig). For metal IBC design types 31A, 31B and 31N, the tests in 
paragraphs (d)(1) and (d)(2) of this section must be conducted 
consecutively.
    (3) For metal IBCs design types 21A, 21B, and 21N, for Packing Group 
I solids: 250 kPa (36 psig) gauge pressure.
    (4) For rigid plastic IBC design types 21H1 and 21H2 and composite 
IBC design types 21HZ1 and 21HZ2: 75 kPa (11 psig).
    (5) For rigid plastic IBC design types 31H1 and 31H2 and composite 
IBC design types 31HZ1 and 31HZ2: whichever is the greater of:
    (i) The pressure determined by any one of the following methods:
    (A) The gauge pressure (pressure in the IBC above ambient 
atmospheric pressure) measured in the IBC at 55 [deg]C

[[Page 240]]

(131 [deg]F) multiplied by a safety factor of 1.5. This pressure must be 
determined on the basis of the IBC being filled and closed to no more 
than 98 percent capacity at 15 [deg]C (60 [deg]F);
    (B) If absolute pressure (vapor pressure of the hazardous material 
plus atmospheric pressure) is used, 1.5 multiplied by the vapor pressure 
of the hazardous material at 55 [deg]C (131 [deg]F) minus 100 kPa (14.5 
psi). If this method is chosen, the hydrostatic test pressure applied 
must be at least 100 kPa gauge pressure (14.5 psig); or
    (C) If absolute pressure (vapor pressure of the hazardous material 
plus atmospheric pressure) is used, 1.75 multiplied by the vapor 
pressure of the hazardous material at 50 [deg]C (122 [deg]F) minus 100 
kPa (14.5 psi). If this method is chosen, the hydrostatic test pressure 
applied must be at least 100 kPa gauge pressure (14.5 psig); or
    (ii) Twice the greater of: (A) The static pressure of the hazardous 
material on the bottom of the IBC filled to 98 percent capacity; or
    (B) The static pressure of water on the bottom of the IBC filled to 
98 percent capacity.
    (e) Criteria for passing the test(s). (1) For metal IBCs, subjected 
to the 65 kPa (9.4 psig) test pressure specified in paragraph (d)(1) of 
this section, there may be no leakage or permanent deformation that 
would make the IBC unsafe for transportation.
    (2) For metal IBCs intended to contain liquids, when subjected to 
the 200 kPa (29 psig) and the 250 kPa (36 psig) test pressures specified 
in paragraphs (d)(2) and (d)(3) of this section, respectively, there may 
be no leakage.
    (3) For rigid plastic IBC types 21H1, 21H2, 31H1, and 31H2, and 
composite IBC types 21HZ1, 21HZ2, 31HZ1, and 31HZ2, there may be no 
leakage and no permanent deformation which renders the IBC unsafe for 
transportation.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 45185, 
45386, Aug. 28, 2001]



Sec. 178.815  Stacking test.

    (a) General. The stacking test must be conducted for the 
qualification of all IBC design types intended to be stacked.
    (b) Special preparation for the stacking test. (1) All IBCs except 
flexible IBC design types must be loaded to their maximum permissible 
gross mass.
    (2) The flexible IBC must be filled to not less than 95 percent of 
its capacity and to its maximum net mass, with the load being evenly 
distributed.
    (c) Test method. (1) Design Qualification Testing. All IBCs must be 
placed on their base on level, hard ground and subjected to a uniformly 
distributed superimposed test load for a period of at least five minutes 
(see paragraph (c)(5) of this section).
    (2) Fiberboard, wooden and composite IBCs with outer packagings 
constructed of other than plastic materials must be subject to the test 
for 24 hours.
    (3) Rigid plastic IBC types and composite IBC types with plastic 
outer packagings (11HH1, 11HH2, 21HH1, 21HH2, 31HH1 and 31HH2) which 
bear the stacking load must be subjected to the test for 28 days at 40 
[deg]C (104 [deg]F).
    (4) For all IBCs, the load must be applied by one of the following 
methods:
    (i) One or more IBCs of the same type loaded to their maximum 
permissible gross mass and stacked on the test IBC;
    (ii) The calculated superimposed test load weight loaded on either a 
flat plate or a reproduction of the base of the IBC, which is stacked on 
the test IBC.
    (5) Calculation of superimposed test load. For all IBCs, the load to 
be placed on the IBC must be 1.8 times the combined maximum permissible 
gross mass of the number of similar IBCs that may be stacked on top of 
the IBC during transportation.
    (d) Periodic Retest. (1) The package must be tested in accordance 
with paragraph (c) of this section; or
    (2) The packaging may be tested using a dynamic compression testing 
machine. The test must be conducted at room temperature on an empty, 
unsealed packaging. The test sample must be centered on the bottom 
platen of the testing machine. The top platen must be lowered until it 
comes in contact with the test sample. Compression must be applied end 
to end. The speed of the compression tester must be one-half inch plus 
or minus one-fourth inch per minute. An initial preload of 50 pounds 
must be applied to ensure a

[[Page 241]]

definite contact between the test sample and the platens. The distance 
between the platens at this time must be recorded as zero deformation. 
The force ``A'' then to be applied must be calculated using the 
applicable formula:

Liquids: A = (1.8)(n - 1) [w + (s x v x 8.3 x .98)] x 1.5;

or

Solids: A = (1.8)(n - 1) [w + (s x v x 8.3 x .95)] x 1.5

Where:

A = applied load in pounds.
n = maximum number of IBCs being stacked during transportation.
w = maximum weight of one empty container in pounds.
s = specific gravity (liquids) or density (solids) of the lading.
v = actual capacity of container (rated capacity + outage) in gallons.
and:
8.3 corresponds to the weight in pounds of 1.0 gallon of water.
1.5 is a compensation factor converting the static load of the stacking 
test into a load suitable for dynamic compression testing.

    (e) Criteria for passing the test. (1) For metal, rigid plastic, and 
composite IBCs, there may be no permanent deformation, which renders the 
IBC unsafe for transportation, and no loss of contents.
    (2) For fiberboard and wooden IBCs, there may be no loss of contents 
and no permanent deformation, which renders the whole IBC, including the 
base pallet, unsafe for transportation.
    (3) For flexible IBCs, there may be no deterioration, which renders 
the IBC unsafe for transportation, and no loss of contents.
    (4) For the dynamic compression test, a container passes the test 
if, after application of the required load, there is no permanent 
deformation to the IBC, which renders the whole IBC, including the base 
pallet, unsafe for transportation; in no case may the maximum deflection 
exceed one inch.

[75 FR 5397, Feb. 2, 2010]



Sec. 178.816  Topple test.

    (a) General. The topple test must be conducted for the qualification 
of all flexible IBC design types.
    (b) Special preparation for the topple test. The flexible IBC must 
be filled to not less than 95 percent of its capacity and to its maximum 
net mass, with the load being evenly distributed.
    (c) Test method. A flexible IBC must be toppled onto any part of its 
top upon a rigid, non-resilient, smooth, flat, and horizontal surface.
    (d) Topple height. For all flexible IBCs, the topple height is 
specified as follows:
    (1) Packing Group I: 1.8 m (5.9 feet).
    (2) Packing Group II: 1.2 m (3.9 feet).
    (3) Packing Group III: 0.8 m (2.6 feet).
    (e) Criteria for passing the test. For all flexible IBCs, there may 
be no loss of contents. A slight discharge (e.g., from closures or 
stitch holes) upon impact is not considered to be a failure, provided no 
further leakage occurs.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.817  Righting test.

    (a) General. The righting test must be conducted for the 
qualification of all flexible IBCs designed to be lifted from the top or 
side.
    (b) Special preparation for the righting test. The flexible IBC must 
be filled to not less than 95 percent of its capacity and to its maximum 
net mass, with the load being evenly distributed.
    (c) Test method. The flexible IBC, lying on its side, must be lifted 
at a speed of at least 0.1 m/second (0.33 ft/s) to an upright position, 
clear of the floor, by one lifting device, or by two lifting devices 
when four are provided.
    (d) Criterion for passing the test. For all flexible IBCs, there may 
be no damage to the IBC or its lifting devices which renders the IBC 
unsafe for transportation or handling.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.818  Tear test.

    (a) General. The tear test must be conducted for the qualification 
of all flexible IBC design types.
    (b) Special preparation for the tear test. The flexible IBC must be 
filled to not less than 95 percent of its capacity and to its maximum 
net mass, the load being evenly distributed.
    (c) Test method. Once the IBC is placed on the ground, a 100-mm (4-
inch) knife score, completely penetrating the

[[Page 242]]

wall of a wide face, is made at a 45[deg] angle to the principal axis of 
the IBC, halfway between the bottom surface and the top level of the 
contents. The IBC must then be subjected to a uniformly distributed 
superimposed load equivalent to twice the maximum net mass. The load 
must be applied for at least five minutes. An IBC which is designed to 
be lifted from the top or the side must, after removal of the 
superimposed load, be lifted clear of the floor and maintained in that 
position for a period of five minutes.
    (d) Criterion for passing the test. The IBC passes the tear test if 
the cut does not propagate more than 25 percent of its original length.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended at 66 FR 45386, 
Aug. 28, 2001]



Sec. 178.819  Vibration test.

    (a) General. The vibration test must be conducted for the 
qualification of all rigid IBC design types. Flexible IBC design types 
must be capable of withstanding the vibration test.
    (b) Test method. (1) A sample IBC, selected at random, must be 
filled and closed as for shipment. IBCs intended for liquids may be 
tested using water as the filling material for the vibration test.
    (2) The sample IBC must be placed on a vibrating platform with a 
vertical or rotary double-amplitude (peak-to-peak displacement) of one 
inch. The IBC must be constrained horizontally to prevent it from 
falling off the platform, but must be left free to move vertically and 
bounce.
    (3) The test must be performed for one hour at a frequency that 
causes the package to be raised from the vibrating platform to such a 
degree that a piece of material of approximately 1.6-mm (0.063-inch) 
thickness (such as steel strapping or paperboard) can be passed between 
the bottom of the IBC and the platform. Other methods at least equally 
effective may be used (see Sec. 178.801(i)).
    (c) Criteria for passing the test. An IBC passes the vibration test 
if there is no rupture or leakage.

[Amdt. 178-103, 59 FR 38074, July 26, 1994, as amended by Amdt. 178-108, 
60 FR 40038, Aug. 4, 1995; Amdt. 178-110, 60 FR 49111, Sept. 21, 1995; 
66 FR 45386, Aug. 28, 2001; 75 FR 5397, Feb. 2, 2010]



                  Subpart P_Large Packagings Standards

    Source: 75 FR 5397, Feb. 2, 2010, unless otherwise noted.



Sec. 178.900  Purpose and scope.

    (a) This subpart prescribes requirements for Large Packaging 
intended for the transportation of hazardous materials. Standards for 
these packagings are based on the UN Recommendations.
    (b) Terms used in this subpart are defined in Sec. 171.8 of this 
subchapter.



Sec. 178.905  Large Packaging identification codes.

    Large packaging code designations consist of: two numerals specified 
in paragraph (a) of this section; followed by the capital letter(s) 
specified in paragraph (b) of this section.
    (a) Large packaging code number designations are as follows: 50 for 
rigid Large Packagings; or 51 for flexible Large Packagings.
    (b) Large Packagings code letter designations are as follows:
    (1) ``A'' means steel (all types and surface treatments).
    (2) ``B'' means aluminum.
    (3) ``C'' means natural wood.
    (4) ``D'' means plywood.
    (5) ``F'' means reconstituted wood.
    (6) ``G'' means fiberboard.
    (7) ``H'' means plastic.
    (8) ``M'' means paper, multiwall.
    (9) ``N'' means metal (other than steel or aluminum).



Sec. 178.910  Marking of Large Packagings.

    (a) The manufacturer must:
    (1) Mark every Large Packaging in a durable and clearly visible 
manner. The marking may be applied in a single line or in multiple lines 
provided the correct sequence is followed with the information required 
by this section.

[[Page 243]]

The following information is required in the sequence presented:
    (i) Except as provided in Sec. 178.503(e)(1)(ii), the United 
Nations packaging symbol as illustrated in Sec. 178.503(e)(1)(i). For 
metal Large Packagings on which the marking is stamped or embossed, the 
capital letters ``UN'' may be applied instead of the symbol;
    (ii) The code number designating the Large Packaging design type 
according to Sec. 178.905. The letter ``W'' must follow the Large 
Packaging design type identification code on a Large Packaging when the 
Large Packaging differs from the requirements in subpart P of this part, 
or is tested using methods other than those specified in this subpart, 
and is approved by the Associate Administrator in accordance with the 
provisions in Sec. 178.955;
    (iii) A capital letter identifying the performance standard under 
which the design type has been successfully tested, as follows:
    (A) X--for Large Packagings meeting Packing Groups I, II and III 
tests;
    (B) Y--for Large Packagings meeting Packing Groups II and III tests; 
and
    (C) Z--for Large Packagings meeting Packing Group III test.
    (iv) The month (designated numerically) and year (last two digits) 
of manufacture;
    (v) The country authorizing the allocation of the mark. The letters 
``USA'' indicate that the Large Packaging is manufactured and marked in 
the United States in compliance with the provisions of this subchapter.
    (vi) The name and address or symbol of the manufacturer or the 
approval agency certifying compliance with subpart P and subpart Q of 
this part. Symbols, if used, must be registered with the Associate 
Administrator.
    (vii) The stacking test load in kilograms (kg). For Large Packagings 
not designed for stacking the figure ``0'' must be shown.
    (viii) The maximum permissible gross mass or for flexible Large 
Packagings, the maximum net mass, in kg.
    (2) The following are examples of symbols and required markings:
    (i) For a steel Large Packaging suitable for stacking; stacking 
load: 2,500 kg; maximum gross mass: 1,000 kg.
[GRAPHIC] [TIFF OMITTED] TR02FE10.003

    (ii) For a plastic Large Packaging not suitable for stacking; 
maximum gross mass: 800 kg.
[GRAPHIC] [TIFF OMITTED] TR02FE10.004

    (iii) For a Flexible Large Packaging not suitable for stacking; 
maximum gross mass: 500 kg.

[[Page 244]]

[GRAPHIC] [TIFF OMITTED] TR02FE10.005

    (b) [Reserved]

[75 FR 5397, Feb. 2, 2010, as amended at 75 FR 60339, Sept. 30, 2010]



Sec. 178.915  General Large Packaging standards.

    (a) Each Large Packaging must be resistant to, or protected from, 
deterioration due to exposure to the external environment. Large 
Packagings intended for solid hazardous materials must be sift-proof and 
water-resistant.
    (b) All service equipment must be positioned or protected to 
minimize potential loss of contents resulting from damage during Large 
Packaging handling and transportation.
    (c) Each Large Packaging, including attachments and service and 
structural equipment, must be designed to withstand, without loss of 
hazardous materials, the internal pressure of the contents and the 
stresses of normal handling and transport. A Large Packaging intended 
for stacking must be designed for stacking. Any lifting or securing 
features of a Large Packaging must be sufficient strength to withstand 
the normal conditions of handling and transportation without gross 
distortion or failure and must be positioned so as to cause no undue 
stress in any part of the Large Packaging.
    (d) A Large Packaging consisting of packagings within a framework 
must be so constructed that the packaging is not damaged by the 
framework and is retained within the framework at all times.
    (e) Large Packaging design types must be constructed in such a way 
as to be bottom-lifted or top-lifted as specified in Sec. Sec. 178.970 
and 178.975.

[75 FR 5397, Feb. 2, 2010, as amended at 75 FR 60339, Sept. 30, 2010]



Sec. 178.920  Standards for metal Large Packagings.

    (a) The provisions in this section apply to metal Large Packagings 
intended to contain liquids and solids. Metal Large Packaging types are 
designated:
    (1) 50A steel
    (2) 50B aluminum
    (3) 50N metal (other than steel or aluminum)
    (b) Each Large Packaging must be made of suitable ductile metal 
materials. Welds must be made so as to maintain design type integrity of 
the receptacle under conditions normally incident to transportation. 
Low-temperature performance must be taken into account when appropriate.
    (c) The use of dissimilar metals must not result in deterioration 
that could affect the integrity of the Large Packaging.
    (d) Metal Large Packagings may not have a volumetric capacity 
greater than 3,000 L (793 gallons) and not less than 450 L (119 
gallons).



Sec. 178.925  Standards for rigid plastic Large Packagings.

    (a) The provisions in this section apply to rigid plastic Large 
Packagings intended to contain liquids and solids. Rigid plastic Large 
Packaging types are designated:
    (1) 50H rigid plastics.
    (2) [Reserved]
    (b) A rigid plastic Large Packaging must be manufactured from 
plastic material of known specifications and be of a strength relative 
to its capacity and to the service it is required to perform. In 
addition to conformance to Sec. 173.24 of this subchapter, plastic 
materials must be resistant to aging and to degradation caused by 
ultraviolet radiation.
    (1) If protection against ultraviolet radiation is necessary, it 
must be provided by the addition of a pigment or inhibiter such as 
carbon black to plastic materials. These additives must be compatible 
with the contents and remain effective throughout the life of the 
plastic Large Packaging body.

[[Page 245]]

Where use is made of carbon black, pigments or inhibitors, other than 
those used in the manufacture of the tested design type, retesting may 
be omitted if changes in the carbon black content, the pigment content 
or the inhibitor content do not adversely affect the physical properties 
of the material of construction.
    (2) Additives may be included in the composition of the plastic 
material to improve the resistance to aging or to serve other purposes, 
provided they do not adversely affect the physical or chemical 
properties of the material of construction.
    (3) No used material other than production residues or regrind from 
the same manufacturing process may be used in the manufacture of rigid 
plastic Large Packagings.
    (c) Rigid plastic Large Packagings:
    (1) May not have a volumetric capacity greater than 3,000 L (793 
gallons); and
    (2) May not have a volumetric capacity less than 450 L (119 
gallons).



Sec. 178.930  Standards for fiberboard Large Packagings.

    (a) The provisions in this section apply to fiberboard Large 
Packagings intended to contain solids. Rigid fiberboard Large Packaging 
types are designated:
    (1) 50G fiberboard
    (2) [Reserved]
    (b) Construction requirements for fiberboard Large Packagings. (1) 
Fiberboard Large Packagings must be constructed of strong, solid or 
double-faced corrugated fiberboard (single or multiwall) that is 
appropriate to the capacity of the Large Packagings and to their 
intended use. Water resistance of the outer surface must be such that 
the increase in mass, as determined in a test carried out over a period 
of 30 minutes by the Cobb method of determining water absorption, is not 
greater than 155 grams per square meter (0.0316 pounds per square 
foot)--see ISO 535 (E) (IBR, see Sec. 171.7 of this subchapter). 
Fiberboard must have proper bending qualities. Fiberboard must be cut, 
creased without cutting through any thickness of fiberboard, and slotted 
so as to permit assembly without cracking, surface breaks or undue 
bending. The fluting or corrugated fiberboard must be firmly glued to 
the facings.
    (i) The walls, including top and bottom, must have a minimum 
puncture resistance of 15 Joules (11 foot-pounds of energy) measured 
according to ISO 3036 (IBR, see Sec. 171.7 of this subchapter).
    (ii) Manufacturers' joints in the outer packaging of Large 
Packagings must be made with an appropriate overlap and be taped, glued, 
stitched with metal staples or fastened by other means at least equally 
effective. Where joints are made by gluing or taping, a water resistant 
adhesive must be used. Metal staples must pass completely through all 
pieces to be fastened and be formed or protected so that any inner liner 
cannot be abraded or punctured by them.
    (2) Integral and detachable pallets. (i) Any integral pallet base 
forming part of a Large Packaging or any detachable pallet must be 
suitable for mechanical handling with the Large Packaging filled to its 
maximum permissible gross mass.
    (ii) The pallet or integral base must be designed to avoid 
protrusions causing damage to the fiberboard Large Packagings in 
handling.
    (iii) The body must be secured to any detached pallet to ensure 
stability in handling and transport. Where a detachable pallet is used, 
its top surface must be free from protrusions that might damage the 
Large Packaging.
    (3) Strengthening devices, such as timber supports to increase 
stacking performance may be used but must be external to the liner.
    (4) The load-bearing surfaces of Large Packagings intended for 
stacking must be designed to distribute the load in a stable manner.
    (c) Fiberboard Large Packagings may not have a volumetric capacity 
greater than 3,000 L (793 gallons) and not less than 450 L (119 
gallons).

[75 FR 5397, Feb. 2, 2010, as amended at 75 FR 60339, Sept. 30, 2010]



Sec. 178.935  Standards for wooden Large Packagings.

    (a) The provisions in this section apply to wooden Large Packagings 
intended to contain solids. Wooden Large Packaging types are designated:
    (1) 50C natural wood.

[[Page 246]]

    (2) 50D plywood.
    (3) 50F reconstituted wood.
    (b) Construction requirements for wooden Large Packagings are as 
follows:
    (1) The strength of the materials used and the method of 
construction must be appropriate to the capacity and intended use of the 
Large Packagings.
    (i) Natural wood used in the construction of Large Packagings must 
be well-seasoned, commercially dry and free from defects that would 
materially lessen the strength of any part of the Large Packagings. Each 
Large Packaging part must consist of uncut wood or a piece equivalent in 
strength and integrity. Large Packagings parts are equivalent to one 
piece when a suitable method of glued assembly is used (i.e., a 
Lindermann joint, tongue and groove joint, ship, lap or babbet joint; or 
butt joint with at least two corrugated metal fasteners at each joint, 
or when other methods at least equally effective are used).
    (ii) Plywood used in construction must be at least 3-ply. Plywood 
must be made of well-seasoned rotary cut, sliced or sawn veneer, 
commercially dry and free from defects that would materially lessen the 
strength of the Large Packagings. All adjacent piles must be glued with 
water resistant adhesive. Materials other than plywood may be used for 
the construction of the Large Packaging.
    (iii) Reconstituted wood used in the construction of Large 
Packagings must be water resistant reconstituted wood such as hardboard, 
particle board or other suitable type.
    (iv) Wooden Large Packagings must be firmly nailed or secured to 
corner posts or ends or be assembled by similar devices.
    (2) Integral and detachable pallets. (i) Any integral pallet base 
forming part of a Large Packaging, or any detachable pallet must be 
suitable for mechanical handling of a Large Packaging filled to its 
maximum permissible gross mass.
    (ii) The pallet or integral base must be designed to avoid 
protrusion that may cause damage to the Large Packaging in handling.
    (iii) The body must be secured to any detachable pallet to ensure 
stability in handling and transportation. Where a detachable pallet is 
used, its top surface must be free from protrusions that might damage 
the Large Packaging.
    (3) Strengthening devices, such as timber supports to increase 
stacking performance, may be used but must be external to the liner.
    (4) The load bearing surfaces of the Large Packaging must be 
designed to distribute loads in a stable manner.
    (c) Wooden Large Packagings:
    (1) May not have a volumetric capacity greater than 3,000 L (793 
gallons); and
    (2) May not have a volumetric capacity less than 450 L (119 
gallons).



Sec. 178.940  Standards for flexible Large Packagings.

    (a) The provisions in this section apply to flexible Large 
Packagings intended to contain liquids and solids. Flexible Large 
Packagings types are designated:
    (1) 51H flexible plastics.
    (2) 51M flexible paper.
    (b) Construction requirements for flexible Large Packagings are as 
follows:
    (1) The strength of the material and the construction of the 
flexible Large Packagings must be appropriate to its capacity and its 
intended use.
    (2) All materials used in the construction of flexible Large 
Packagings of types 51M must, after complete immersion in water for not 
less than 24 hours, retain at least 85 percent of the tensile strength 
as measured originally on the material conditioned to equilibrium at 67 
percent relative humidity or less.
    (3) Seams must be stitched or formed by heat sealing, gluing or any 
equivalent method. All stitched seam-ends must be secured.
    (4) In addition to conformance with the requirements of Sec. 173.24 
of this subchapter, flexible Large Packaging must be resistant to aging 
and degradation caused by ultraviolet radiation.
    (5) For plastic flexible Large Packagings, if necessary, protection 
against ultraviolet radiation must be provided by the addition of 
pigments or inhibitors such as carbon black. These additives must be 
compatible with the contents and remain effective throughout

[[Page 247]]

the life of the Large Packaging. Where use is made of carbon black, 
pigments or inhibitors other than those used in the manufacture of the 
tested design type, retesting may be omitted if the carbon black 
content, the pigment content or the inhibitor content do not adversely 
affect the physical properties of the material of construction.
    (6) Additives may be included in the composition of the material of 
the Large Packaging to improve the resistance to aging, provided they do 
not adversely affect the physical or chemical properties of the 
material.
    (7) When flexible material Large Packagings are filled, the ratio of 
height to width must be no more than 2:1.
    (c) Flexible Large Packagings:
    (1) May not have a volumetric capacity greater than 3,000 L (793 
gallons);
    (2) May not have a volumetric capacity less than 56 L (15 gallons); 
and
    (3) Must be designed and tested to a capacity of not less than 50 kg 
(110 pounds).



                  Subpart Q_Testing of Large Packagings

    Source: 75 FR 5400, Feb. 2, 2010, unless otherwise noted.



Sec. 178.950  Purpose and scope.

    This subpart prescribes certain testing requirements for Large 
Packagings identified in subpart P of this part.



Sec. 178.955  General requirements.

    (a) General. The test procedures prescribed in this subpart are 
intended to ensure that Large Packagings containing hazardous materials 
can withstand normal conditions of transportation. These test procedures 
are considered minimum requirements. Each packaging must be manufactured 
and assembled so as to be capable of successfully passing the prescribed 
tests and to conform to the requirements of Sec. 173.24 of this 
subchapter while in transportation.
    (b) Responsibility. The Large Packaging manufacturer is responsible 
for ensuring each Large Packaging is capable of passing the prescribed 
tests. To the extent a Large Packaging's assembly function, including 
final closure, is performed by the person who offers a hazardous 
material for transportation, that person is responsible for performing 
the function in accordance with Sec. Sec. 173.22 and 178.2 of this 
subchapter.
    (c) Definitions. For the purpose of this subpart:
    (1) Large packaging design type refers to a Large Packaging which 
does not differ in structural design, size, material of construction and 
packing.
    (2) Design qualification testing is the performance of the drop, 
stacking, and bottom-lift or top-lift tests, as applicable, prescribed 
in this subpart, for each different Large Packaging design type, at the 
start of production of that packaging.
    (3) Periodic design requalification test is the performance of the 
applicable tests specified in paragraph (c)(2) of this section on a 
Large Packaging design type, to requalify the design for continued 
production at the frequency specified in paragraph (e) of this section.
    (4) Production inspection is the inspection, which must initially be 
conducted on each newly manufactured Large Packaging.
    (5) Different Large Packaging design type is one which differs from 
a previously qualified Large Packaging design type in structural design, 
size, material of construction, wall thickness, or manner of 
construction, but does not include:
    (i) A packaging which differs in surface treatment;
    (ii) A rigid plastic Large Packaging, which differs with regard to 
additives used to comply with Sec. 178.925(b) or Sec. 178.940(b);
    (iii) A packaging which differs only in its lesser external 
dimensions (i.e., height, width, length) provided materials of 
construction and material thickness or fabric weight remain the same;
    (6) Remanufactured Large Packaging is a metal or rigid Large 
Packaging that is produced as a UN type from a non-UN type or is 
converted from one UN design type to another UN design type. 
Remanufactured Large Packagings are subject to the same requirements of 
this subchapter that apply to new Large Packagings of the same type.

[[Page 248]]

    (7) Reused Large Packaging is a Large Packaging intended to be 
refilled and has been examined and found free of defects affecting its 
ability to withstand the performance tests. See also Sec. 173.36(c) of 
this subchapter.
    (d) Design qualification testing. The packaging manufacturer must 
achieve successful test results for the design qualification testing at 
the start of production of each new or different Large Packaging design 
type. Application of the certification mark by the manufacturer 
constitutes certification that the Large Packaging design type passed 
the prescribed tests in this subpart.
    (e) Periodic design requalification testing. (1) Periodic design 
requalification must be conducted on each qualified Large Packaging 
design type if the manufacturer is to maintain authorization for 
continued production. The Large Packaging manufacturer must achieve 
successful test results for the periodic design requalification at 
sufficient frequency to ensure each packaging produced by the 
manufacturer is capable of passing the design qualification tests. 
Design requalification tests must be conducted at least once every 24 
months.
    (2) Changes in the frequency of design requalification testing 
specified in paragraph (e)(1) of this section are authorized if approved 
by the Associate Administrator.
    (f) Test samples. The manufacturer must conduct the design 
qualification and periodic tests prescribed in this subpart using random 
samples of packagings, in the numbers specified in the appropriate test 
section.
    (g) Selective testing. The selective testing of Large Packagings, 
which differ only in minor respects from a tested type is permitted as 
described in this section. For air transport, Large Packagings must 
comply with Sec. 173.27(c)(1) and (c)(2) of this subchapter. Variations 
are permitted in inner packagings of a tested Large Packaging, without 
further testing of the package, provided an equivalent level of 
performance is maintained and the methodology used to determine that the 
inner packaging, including closure, maintains an equivalent level of 
performance is documented in writing by the person certifying compliance 
with this paragraph and retained in accordance with paragraph (l) of 
this section. Permitted variations are as follows:
    (1) Inner packagings of equivalent or smaller size may be used 
provided--
    (i) The inner packagings are of similar design to the tested inner 
packagings (i.e., shape--round, rectangular, etc.);
    (ii) The material of construction of the inner packagings (glass, 
plastic, metal, etc.) offers resistance to impact and stacking forces 
equal to or greater than that of the originally tested inner packaging;
    (iii) The inner packagings have the same or smaller openings and the 
closure is of similar design (e.g., screw cap, friction lid, etc.);
    (iv) Sufficient additional cushioning material is used to take up 
void spaces and to prevent significant movement of the inner packagings;
    (v) Inner packagings are oriented within the outer packaging in the 
same manner as in the tested package; and
    (vi) The gross mass of the package does not exceed that originally 
tested.
    (2) A lesser number of the tested inner packagings, or of the 
alternative types of inner packagings identified in paragraph (g)(1) of 
this section, may be used provided sufficient cushioning is added to 
fill void space(s) and to prevent significant movement of the inner 
packagings.
    (h) Proof of compliance. In addition to the periodic design 
requalification testing intervals specified in paragraph (e) of this 
section, the Associate Administrator, or a designated representative, 
may at any time require demonstration of compliance by a manufacturer, 
through testing in accordance with this subpart, to ensure packagings 
meet the requirements of this subpart. As required by the Associate 
Administrator, or a designated representative, the manufacturer must 
either:
    (1) Conduct performance tests or have tests conducted by an 
independent testing facility, in accordance with this subpart; or
    (2) Make a sample Large Packaging available to the Associate 
Administrator, or a designated representative,

[[Page 249]]

for testing in accordance with this subpart.
    (i) Record retention. Following each design qualification test and 
each periodic retest on a Large Packaging, a test report must be 
prepared. The test report must be maintained at each location where the 
Large Packaging is manufactured and each location where the design 
qualification tests are conducted, for as long as the Large Packaging is 
produced and for at least two years thereafter, and at each location 
where the periodic retests are conducted until such tests are 
successfully performed again and a new test report produced. In 
addition, a copy of the test report must be maintained by a person 
certifying compliance with this part. The test report must be made 
available to a user of a Large Packaging or a representative of the 
Department upon request. The test report, at a minimum, must contain the 
following information:
    (1) Name and address of test facility;
    (2) Name and address of applicant (where appropriate);
    (3) A unique test report identification;
    (4) Date of the test report;
    (5) Manufacturer of the packaging;
    (6) Description of the packaging design type (e.g., dimensions, 
materials, closures, thickness, etc.), including methods of manufacture 
(e.g., blow molding) and which may include drawing(s) and/or 
photograph(s);
    (7) Maximum capacity;
    (8) Characteristics of test contents, e.g., viscosity and relative 
density for liquids and particle size for solids;
    (9) Mathematical calculations performed to conduct and document 
testing (for example, drop height, test capacity, outage requirements, 
etc.);
    (10) Test descriptions and results; and
    (11) Signature with the name and title of signatory.

[75 FR 5400, Feb. 2, 2010, as amended at 75 FR 60339, Sept. 30, 2010; 76 
FR 3389, Jan. 19, 2011]



Sec. 178.960  Preparation of Large Packagings for testing.

    (a) Except as otherwise provided in this subchapter, each Large 
Packaging and package must be closed in preparation for testing and 
tests must be carried out in the same manner as if prepared for 
transportation, including inner packagings. All closures must be 
installed using proper techniques and torques.
    (b) For the drop and stacking test, inner receptacles must be filled 
to not less than 95 percent of maximum capacity (see Sec. 171.8 of this 
subchapter) in the case of solids and not less than 98 percent of 
maximum in the case of liquids. Bags must be filled to the maximum mass 
at which they may be used. For Large Packagings where the inner 
packagings are designed to carry liquids and solids, separate testing is 
required for both liquid and solid contents. The material to be 
transported in the packagings may be replaced by a non-hazardous 
material, except for chemical compatibility testing or where this would 
invalidate the results of the tests.
    (c) If the material to be transported is replaced for test purposes 
by a non-hazardous material, the material used must be of the same or 
higher specific gravity as the material to be carried, and its other 
physical properties (grain, size, viscosity) which might influence the 
results of the required tests must correspond as closely as possible to 
those of the hazardous material to be transported. It is permissible to 
use additives, such as bags of lead shot, to achieve the requisite total 
package mass, so long as they do not affect the test results.
    (d) Paper or fiberboard Large Packagings must be conditioned for at 
least 24 hours immediately prior to testing in an atmosphere 
maintained--
    (1) At 50 percent 2 percent relative humidity, 
and at a temperature of 23 [deg]C 2 [deg]C (73 
[deg]F 4 [deg]F). Average values should fall 
within these limits. Short-term fluctuations and measurement limitations 
may cause individual measurements to vary by up to 5 percent relative humidity without significant 
impairment of test reproducibility;
    (2) At 65 percent 2 percent relative humidity, 
and at a temperature of 20 [deg]C 2 [deg]C (68 
[deg]F 4 [deg]F), or 27 [deg]C 2 [deg]C (81 [deg]F 4 [deg]F). 
Average values should fall within these limits. Short-term fluctuations 
and measurement limitations may cause individual measurements to

[[Page 250]]

vary by up to 5 percent relative humidity without 
significant impairment of test reproducibility; or
    (3) For testing at periodic intervals only (i.e., other than initial 
design qualification testing), at ambient conditions.



Sec. 178.965  Drop test.

    (a) General. The drop test must be conducted for the qualification 
of all Large Packaging design types and performed periodically as 
specified in Sec. 178.955(e) of this subpart.
    (b) Special preparation for the drop test. Large Packagings must be 
filled in accordance with Sec. 178.960.
    (c) Conditioning. Rigid plastic Large Packagings and Large 
Packagings with plastic inner receptacles must be conditioned for 
testing by reducing the temperature of the packaging and its contents to 
-18 [deg]C (0 [deg]F) or lower. Test liquids must be kept in the liquid 
state, if necessary, by the addition of anti-freeze. Water/anti-freeze 
solutions with a minimum specific gravity of 0.95 for testing at -18 
[deg]C (0 [deg]F) or lower are considered acceptable test liquids, and 
may be considered equivalent to water for test purposes. Large 
Packagings conditioned in this way are not required to be conditioned in 
accordance with Sec. 178.960(d).
    (d) Test method. (1) Samples of all Large Packaging design types 
must be dropped onto a rigid, non-resilient, smooth, flat and horizontal 
surface. The point of impact must be the most vulnerable part of the 
base of the Large Packaging being tested. Following the drop, the Large 
Packaging must be restored to the upright position for observation.
    (2) Large Packaging design types with a capacity of 0.45 cubic 
meters (15.9 cubic feet) or less must be subject to an additional drop 
test.
    (e) Drop height. (1) For all Large Packagings, drop heights are 
specified as follows:
    (i) Packing group I: 1.8 m (5.9 feet)
    (ii) Packing group II: 1.2 m (3.9 feet)
    (iii) Packing group III: 0.8 m (2.6 feet)
    (2) Drop tests are to be performed with the solid or liquid to be 
transported or with a non-hazardous material having essentially the same 
physical characteristics.
    (3) The specific gravity and viscosity of a substituted non-
hazardous material used in the drop test for liquids must be similar to 
the hazardous material intended for transportation. Water also may be 
used for the liquid drop test under the following conditions:
    (i) Where the substances to be carried have a specific gravity not 
exceeding 1.2, the drop heights must be those specified in paragraph 
(e)(1) of this section for each Large Packaging design type; and
    (ii) Where the substances to be carried have a specific gravity 
exceeding 1.2, the drop heights must be as follows:
    (A) Packing Group I: SG x 1.5 m (4.9 feet).
    (B) Packing Group II: SG x 1.0 m (3.3 feet).
    (C) Packing Group III: SG x 0.67 m (2.2 feet).
    (f) Criteria for passing the test. For all Large Packaging design 
types there may be no loss of the filling substance from inner 
packaging(s) or article(s). Ruptures are not permitted in Large 
Packaging for articles of Class 1 which permit the spillage of loose 
explosive substances or articles from the Large Packaging. Where a Large 
Packaging undergoes a drop test, the sample passes the test if the 
entire contents are retained even if the closure is no longer sift-
proof.

[75 FR 5400, Feb. 2, 2010, as amended at 75 FR 60339, Sept. 30, 2010]



Sec. 178.970  Bottom lift test.

    (a) General. The bottom lift test must be conducted for the 
qualification of all Large Packagings design types designed to be lifted 
from the base.
    (b) Special preparation for the bottom lift test. The Large 
Packaging must be loaded to 1.25 times its maximum permissible gross 
mass, the load being evenly distributed.
    (c) Test method. All Large Packaging design types must be raised and 
lowered twice by a lift truck with the forks centrally positioned and 
spaced at three quarters of the dimension of the side of entry (unless 
the points of entry are fixed). The forks must penetrate to three 
quarters of the direction of entry.

[[Page 251]]

    (d) Criteria for passing the test. For all Large Packagings design 
types designed to be lifted from the base, there may be no permanent 
deformation which renders the Large Packaging unsafe for transport and 
there must be no loss of contents.



Sec. 178.975  Top lift test.

    (a) General. The top lift test must be conducted for the 
qualification of all of Large Packagings design types to be lifted from 
the top or, for flexible Large Packagings, from the side.
    (b) Special preparation for the top lift test. (1) Metal and rigid 
plastic Large Packagings design types must be loaded to twice its 
maximum permissible gross mass.
    (2) Flexible Large Packaging design types must be filled to six 
times the maximum permissible gross mass, the load being evenly 
distributed.
    (c) Test method. (1) A Large Packaging must be lifted in the manner 
for which it is designed until clear of the floor and maintained in that 
position for a period of five minutes.
    (2) Rigid plastic Large Packaging design types must be:
    (i) Lifted by each pair of diagonally opposite lifting devices, so 
that the hoisting forces are applied vertically for a period of five 
minutes; and
    (ii) Lifted by each pair of diagonally opposite lifting devices so 
that the hoisting forces are applied towards the center at 45[deg] to 
the vertical, for a period of five minutes.
    (3) If not tested as indicated in paragraph (c)(1) of this section, 
a flexible Large Packaging design type must be tested as follows:
    (i) Fill the flexible Large Packaging to 95% full with a material 
representative of the product to be shipped.
    (ii) Suspend the flexible Large Packaging by its lifting devices.
    (iii) Apply a constant downward force through a specially designed 
platen. The platen will be a minimum of 60 percent and a maximum of 80 
percent of the cross sectional surface area of the flexible Large 
Packaging.
    (iv) The combination of the mass of the filled flexible Large 
Packaging and the force applied through the platen must be a minimum of 
six times the maximum net mass of the flexible Large Packaging. The test 
must be conducted for a period of five minutes.
    (v) Other equally effective methods of top lift testing and 
preparation may be used with approval of the Associate Administrator.
    (d) Criterion for passing the test. For all Large Packagings design 
types designed to be lifted from the top, there may be no permanent 
deformation which renders the Large Packagings unsafe for transport and 
no loss of contents.



Sec. 178.980  Stacking test.

    (a) General. The stacking test must be conducted for the 
qualification of all Large Packagings design types intended to be 
stacked.
    (b) Special preparation for the stacking test. (1) All Large 
Packagings except flexible Large Packaging design types must be loaded 
to their maximum permissible gross mass.
    (2) Flexible Large Packagings must be filled to not less than 95 
percent of their capacity and to their maximum net mass, with the load 
being evenly distributed.
    (c) Test method. (1) All Large Packagings must be placed on their 
base on level, hard ground and subjected to a uniformly distributed 
superimposed test load for a period of at least five minutes (see 
paragraph (c)(5) of this section).
    (2) Fiberboard and wooden Large Packagings must be subjected to the 
test for 24 hours.
    (3) Rigid plastic Large Packagings which bear the stacking load must 
be subjected to the test for 28 days at 40 [deg]C (104 [deg]F).
    (4) For all Large Packagings, the load must be applied by one of the 
following methods:
    (i) One or more Large Packagings of the same type loaded to their 
maximum permissible gross mass and stacked on the test Large Packaging;
    (ii) The calculated superimposed test load weight loaded on either a 
flat plate or a reproduction of the base of the Large Packaging, which 
is stacked on the test Large Packaging; or
    (5) Calculation of superimposed test load. For all Large Packagings, 
the load to be placed on the Large Packaging must be 1.8 times the 
combined

[[Page 252]]

maximum permissible gross mass of the number of similar Large Packaging 
that may be stacked on top of the Large Packaging during transportation.
    (d) Periodic Retest. (1) The package must be tested in accordance 
with Sec. 178.980(c) of this subpart; or
    (2) The packaging may be tested using a dynamic compression testing 
machine. The test must be conducted at room temperature on an empty, 
unsealed packaging. The test sample must be centered on the bottom 
platen of the testing machine. The top platen must be lowered until it 
comes in contact with the test sample. Compression must be applied end 
to end. The speed of the compression tester must be one-half inch plus 
or minus one-fourth inch per minute. An initial preload of 50 pounds 
must be applied to ensure a definite contact between the test sample and 
the platens. The distance between the platens at this time must be 
recorded as zero deformation. The force ``A'' to then be applied must be 
calculated using the applicable formula:

Liquids: A = (1.8)(n-1) [w + (s x v x 8.3 x .98)] x 1.5;


or

Solids: A = (1.8)(n-1) [w + (s x v x 8.3 x .95)] x 1.5

Where:

A = applied load in pounds.
n = maximum number of Large Packagings that may be stacked during 
          transportation.
w = maximum weight of one empty container in pounds.
s = specific gravity (liquids) or density (solids) of the lading.
v = actual capacity of container (rated capacity + outage) in gallons.
and:
8.3 corresponds to the weight in pounds of 1.0 gallon of water.
1.5 is a compensation factor that converts the static load of the 
          stacking test into a load suitable for dynamic compression 
          testing.

    (e) Criterion for passing the test. (1) For metal or rigid plastic 
Large Packagings, there may be no permanent deformation which renders 
the Large Packaging unsafe for transportation and no loss of contents.
    (2) For flexible Large Packagings, there may be no deterioration 
which renders the Large Packaging unsafe for transportation and no loss 
of contents.
    (3) For the dynamic compression test, a container passes the test 
if, after application of the required load, there is no permanent 
deformation to the Large Packaging which renders the whole Large 
Packaging; including the base pallet, unsafe for transportation; in no 
case may the maximum deflection exceed one inch.

[75 FR 5400, Feb. 2, 2010, as amended at 75 FR 60339, Sept. 30, 2010]



Sec. 178.985  Vibration test.

    (a) General. All rigid Large Packaging and flexible Large Packaging 
design types must be capable of withstanding the vibration test.
    (b) Test method. (1) A sample Large Packaging, selected at random, 
must be filled and closed as for shipment. Large Packagings intended for 
liquids may be tested using water as the filling material for the 
vibration test.
    (2) The sample Large Packaging must be placed on a vibrating 
platform that has a vertical or rotary double-amplitude (peak-to-peak 
displacement) of one inch. The Large Packaging must be constrained 
horizontally to prevent it from falling off the platform, but must be 
left free to move vertically and bounce.
    (3) The sample Large Packaging must be placed on a vibrating 
platform that has a vertical double-amplitude (peak-to-peak 
displacement) of one inch. The Large Packaging must be constrained 
horizontally to prevent it from falling off the platform, but must be 
left free to move vertically and bounce.
    (4) The test must be performed for one hour at a frequency that 
causes the package to be raised from the vibrating platform to such a 
degree that a piece of material of approximately 1.6-mm (0.063-inch) in 
thickness (such as steel strapping or paperboard) can be passed between 
the bottom of the Large Packaging and the platform. Other methods at 
least equally effective may be used (see Sec. 178.801(i)).
    (c) Criterion for passing the test. A Large Packaging passes the 
vibration test if there is no rupture or leakage.

[75 FR 5400, Feb. 2, 2010, as amended at 75 FR 60339, Sept. 30, 2010]

[[Page 253]]



          Sec. Appendix A to Part 178--Specifications for Steel

                                                     Table 1
 [Open-hearth, basic oxygen, or electric steel of uniform quality. The following chemical composition limits are
                                            based on ladle analysis:]
----------------------------------------------------------------------------------------------------------------
                                                      Chemical composition, percent-ladle analysis
             Designation              --------------------------------------------------------------------------
                                             Grade 1 \1\             Grade 2 \1,2\           Grade 3 \2,4,5\
----------------------------------------------------------------------------------------------------------------
Carbon...............................  0.10/0.20..............  0.24 maximum...........  0.22 maximum.
Manganese............................  1.10/1.60..............  0.50/1.00..............  1.25 maximum.
Phosphorus, maximum..................  0.04...................  0.04...................  0.045.\6\
Sulfur, maximum......................  0.05...................  0.05...................  0.05.
Silicon..............................  0.15/0.30..............  0.30 maximum...........  .......................
Copper, maximum......................  0.40...................  .......................  .......................
Columbium............................  .......................  0.01/0.04..............  .......................
Heat treatment authorized............  (\3\)..................  (\3\)..................  (\3\).
Maximum stress (p.s.i.)..............  35,000.................  35,000.................  35,000.
----------------------------------------------------------------------------------------------------------------
\1\ Addition of other elements to obtain alloying effect is not authorized.
\2\ Ferritic grain size 6 or finer according to ASTM E 112-96 (IBR, see Sec. 171.7 of this subchapter).
\3\ Any suitable heat treatment in excess of 1,100 [deg]F., except that liquid quenching is not permitted.
\4\ Other alloying elements may be added and shall be reported.
\5\ For compositions with a maximum carbon content of 0.15 percent of ladle analysis, the maximum limit for
  manganese on ladle analysis may be 1.40 percent.
\6\ Rephosphorized Grade 3 steels containing no more than 0.15 percent phosphorus are permitted if carbon
  content does not exceed 0.15 percent and manganese does not exceed 1 percent.


                                            Check Analysis Tolerances
     [A heat of steel made under any of the above grades, the ladle analysis of which is slightly out of the
            specified range is acceptable if the check analysis is within the following variations:]
----------------------------------------------------------------------------------------------------------------
                                                                                           Tolerance (percent)
                                                                                          over the maximum limit
                                                                                           or under the minimum
                                                                                                  limit
                    Element                       Limit or maximum specified (percent)  ------------------------
                                                                                            Under        Over
                                                                                           minimum      maximum
                                                                                            limit        limit
----------------------------------------------------------------------------------------------------------------
Carbon.........................................  To 0.15 inclusive.....................        0.02         0.03
                                                 Over 0.15 to 0.40 inclusive...........        0.03         0.04
Manganese......................................  To 0.60 inclusive.....................        0.03         0.03
                                                 Over 0.60 to 1.15 inclusive...........        0.04         0.04
                                                 Over 1.15 to 2.50 inclusive...........        0.05         0.05
Phosphorus \7\.................................  All ranges............................  ...........        0.01
Sulfur.........................................  All ranges............................  ...........        0.01
Silicon........................................  To 0.30 inclusive.....................        0.02         0.03
                                                 Over 0.30 to 1.00 inclusive...........        0.05         0.05
Copper.........................................  To 1.00 inclusive.....................        0.03         0.03
                                                 Over 1.00 to 2.00 inclusive...........        0.05         0.05
Nickel.........................................  To 1.00 inclusive.....................        0.03         0.03
                                                 Over 1.00 to 2.00 inclusive...........        0.05         0.05
Chromium.......................................  To 0.90 inclusive.....................        0.03         0.03
                                                 Over 0.90 to 2.10 inclusive...........        0.05         0.05
Molybdenum.....................................  To 0.20 inclusive.....................        0.01         0.01
                                                 Over 0.20 to 0.40 inclusive...........        0.02         0.02
Zirconium......................................  All ranges............................        0.01         0.05
Columbium......................................  To 0.04 inclusive.....................        0.005        0.01
Aluminum.......................................  Over 0.10 to 0.20 inclusive...........        0.04         0.04
                                                 Over 0.20 to 0.30 inclusive...........        0.05         0.05
----------------------------------------------------------------------------------------------------------------
\7\ Rephosphorized steels not subject to check analysis for phosphorus.


[Amdt. 178-3, 34 FR 12283, July 25, 1969; 34 FR 12593, Aug. 1, 1969, as 
amended by Amdt. 178-64, 45 FR 81573, Dec. 11, 1980; Amdt. 178-97, 55 FR 
52728, Dec. 21, 1990; 68 FR 75758, Dec. 31, 2003]



   Sec. Appendix B to Part 178--Alternative Leakproofness
   Test Methods

    In addition to the method prescribed in Sec. 178.604 of this 
subchapter, the following leakproofness test methods are authorized:
    (1) Helium test. The packaging must be filled with at least 1 L 
inert helium gas, air tight closed, and placed in a testing chamber. The 
testing chamber must be evacuated down to a pressure of 5 kPa which 
equals an over-pressure inside the packaging of 95 kPa.

[[Page 254]]

The air in the testing chamber must be analyzed for traces of helium gas 
by means of a mass spectrograph. The test must be conducted for a period 
of time sufficient to evacuate the chamber and to determine if there is 
leakage into or out of the packaging. If helium gas is detected, the 
leaking packaging must be automatically separated from non-leaking drums 
and the leaking area determined according to the method prescribed in 
Sec. 178.604(d) of this subchapter. A packaging passes the test if 
there is no leakage of helium.
    (2) Pressure differential test. The packaging shall be restrained 
while either pressure or a vacuum is applied internally. The packaging 
must be pressurized to the pressure required by Sec. 178.604(e) of this 
subchapter for the appropriate packing group. The method of restraint 
must not affect the results of the test. The test must be conducted for 
a period of time sufficient to appropriately pressurize or evacuate the 
interior of the packaging and to determine if there is leakage into or 
out of the packaging. A packaging passes the pressure differential test 
if there is no change in measured internal pressure.
    (3) Solution over seams. The packaging must be restrained while an 
internal air pressure is applied; the method of restraint may not affect 
the results of the test. The exterior surface of all seams and welds 
must be coated with a solution of soap suds or a water and oil mixture. 
The test must be conducted for a period of time sufficient to pressurize 
the interior of the packaging to the specified air pressure and to 
determine if there is leakage of air from the packaging. A packaging 
passes the test if there is no leakage of air from the packaging.
    (4) Solution over partial seams test. For other than design 
qualification testing, the following test may be used for metal drums: 
The packaging must be restrained while an internal air pressure of 48 
kPa (7.0 psig) is applied; the method of restraint may not affect the 
results of the test. The packaging must be coated with a soap solution 
over the entire side seam and a distance of not less than eight inches 
on each side of the side seam along the chime seam(s). The test must be 
conducted for a period of time sufficient to pressurize the interior of 
the packaging to the specified air pressure and to determine if there is 
leakage of air from the packaging. A packaging passes the test if there 
is no leakage of air from the packaging. Chime cuts must be made on the 
initial drum at the beginning of each production run and on the initial 
drum after any adjustment to the chime seamer. Chime cuts must be 
maintained on file in date order for not less than six months and be 
made available to a representative of the Department of Transportation 
on request.

[Amdt. 178-97, 55 FR 52728, Dec. 21, 1990, as amended at 56 FR 66287, 
Dec. 20, 1991; 57 FR 45466, Oct. 1, 1992]



 Sec. Appendix C to Part 178--Nominal and Minimum Thicknesses of Steel 
                           Drums and Jerricans

    For each listed packaging capacity, the following table compares the 
ISO 3574 (IBR, see Sec. 171.7 of this subchapter) nominal thickness 
with the corresponding ISO 3574 minimum thickness.

------------------------------------------------------------------------
                                                   ISO     Corresponding
             Maximum capacity (L)                nominal    ISO minimum
                                                  (mm)          (mm)
------------------------------------------------------------------------
20...........................................         0.7          0.63
30...........................................         0.8          0.73
40...........................................         0.8          0.73
60...........................................         1.0          0.92
120..........................................         1.0          0.92
220..........................................         1.0          0.92
450..........................................         1.9          1.77
------------------------------------------------------------------------


[Amdt. 178-106, 59 FR 67522, Dec. 29, 1994, as amended at 68 FR 75758, 
Dec. 31, 2003]



          Sec. Appendix D to Part 178--Thermal Resistance Test

    1. Scope. This test method evaluates the thermal resistance 
capabilities of a compressed oxygen generator and the outer packaging 
for a cylinder of compressed oxygen or other oxidizing gas and an oxygen 
generator. When exposed to a temperature of 205 [deg]C (400 [deg]F) for 
a period of not less than three hours, the outer surface of the cylinder 
may not exceed a temperature of 93 [deg]C (199 [deg]F) and the oxygen 
generator must not actuate.
    2. Apparatus.
    2.1 Test Oven. The oven must be large enough in size to fully house 
the test outer package without clearance problems. The test oven must be 
capable of maintaining a minimum steady state temperature of 205 [deg]C 
(400 [deg]F).
    2.2 Thermocouples. At least three thermocouples must be used to 
monitor the temperature inside the oven and an additional three 
thermocouples must be used to monitor the temperature of the cylinder. 
The thermocouples must be \1/16\ inch, ceramic packed, metal sheathed, 
type K (Chromel-Alumel), grounded junction with a nominal 30 American 
wire gauge (AWG) size conductor. The thermocouples measuring the 
temperature inside the oven must be placed at varying heights to ensure 
even temperature and proper heat-soak conditions. For

[[Page 255]]

the thermocouples measuring the temperature of the cylinder: (1) Two of 
them must be placed on the outer cylinder side wall at approximately 2 
inches (5 cm) from the top and bottom shoulders of the cylinder; and (2) 
one must be placed on the cylinder valve body near the pressure relief 
device. Alternatively, the thermocouples may be replaced with other 
devices such as a remote temperature sensor, metal fuse on the valve, or 
coated wax, provided the device is tested and the test report is 
retained for verification. Under this alternative, it is permissible to 
record the highest temperature to which the cylinder is subjected 
instead of temperature measurements in intervals of not more than five 
(5) minutes.
    2.3 Instrumentation. A calibrated recording device or a computerized 
data acquisition system with an appropriate range should be provided to 
measure and record the outputs of the thermocouples.
    3. Test Specimen.
    3.1 Specimen Configuration. Each outer package material type and 
design must be tested, including any features such as handles, latches, 
fastening systems, etc., that may compromise the ability of the outer 
package to provide thermal protection.
    3.2 Test Specimen Mounting. The tested outer package must be 
supported at the four corners using fire brick or other suitable means. 
The bottom surface of the outer package must be exposed to allow 
exposure to heat.
    4. Preparation for Testing.
    4.1 It is recommended that the cylinder be closed at ambient 
temperature and configured as when filled with a valve and pressure 
relief device. The oxygen generator must be filled with an oxidizing 
agent and may be tested with or without packaging.
    4.2 Place the package or generator onto supporting bricks or a stand 
inside the test oven in such a manner to ensure even temperature flow.
    5. Test Procedure.
    5.1 Close oven door and check for proper reading on thermocouples.
    5.2 Raise the temperature of the oven to a minimum temperature of 
205 [deg]C 2 [deg]C (400 [deg]F 5 [deg]F). Maintain a minimum oven temperature of 205 
[deg]C 2 [deg]C (400 [deg]F 5 [deg]F) for at least three hours. Exposure time begins 
when the oven steady state temperature reaches a minimum of 205 [deg]C 
2 [deg]C (400 [deg]F 5 
[deg]F).
    5.3 At the conclusion of the three-hour period, the outer package 
may be removed from the oven and allowed to cool naturally.
    6. Recordkeeping.
    6.1 Record a complete description of the material being tested, 
including the manufacturer, size of cylinder, etc.
    6.2 Record any observations regarding the behavior of the test 
specimen during exposure, such as smoke production, delamination, resin 
ignition, and time of occurrence of each event.
    6.3 Record the temperature and time history of the cylinder 
temperature during the entire test for each thermocouple location. 
Temperature measurements must be recorded at intervals of not more than 
five (5) minutes. Record the maximum temperatures achieved at all three 
thermocouple locations and the corresponding time.
    7. Requirements.
    7.1 For a cylinder, the outer package must provide adequate 
protection such that the outer surface of the cylinder and valve does 
not exceed a temperature of 93 [deg]C (199 [deg]F) at any of the three 
points where the thermocouples are located.
    7.2 For an oxygen generator, the generator must not actuate.

[72 FR 4457, Jan. 31, 2008, as amended at 72 FR 55099, Sept. 28, 2007]



     Sec. Appendix E to Part 178--Flame Penetration Resistance Test

    (a) Criteria for Acceptance. (1) At least three specimens of the 
outer packaging materials must be tested;
    (2) Each test must be conducted on a flat 16 inch x 24 inch test 
specimen mounted in the horizontal ceiling position of the test 
apparatus to represent the outer packaging design;
    (3) Testing must be conducted on all design features (latches, 
seams, hinges, etc.) affecting the ability of the outer packaging to 
safely prevent the passage of fire in the horizontal ceiling position; 
and
    (4) There must be no flame penetration of any specimen within 5 
minutes after application of the flame source and the maximum allowable 
temperature at a point 4 inches above the test specimen, centered over 
the burner cone, must not exceed 205 [deg]C (400 [deg]F).
    (b) Summary of Method. This method provides a laboratory test 
procedure for measuring the capability of cargo compartment lining 
materials to resist flame penetration with a 2 gallon per hour (GPH) 
2 Grade kerosene or equivalent burner fire source. Ceiling and 
sidewall liner panels may be tested individually provided a baffle is 
used to simulate the missing panel. Any specimen that passes the test as 
a ceiling liner panel may be used as a sidewall liner panel.
    (c) Test Specimens. (1) The specimen to be tested must measure 16 
\1/8\ inches (406 3 mm) by 
24+\1/8\ inches (610 3 mm).
    (2) The specimens must be conditioned at 70 [deg]F. 5 [deg]F. (21 [deg]C. 2 [deg]C.) 
and 55% 5% humidity for at least 24 hours before 
testing.
    (d) Test Apparatus. The arrangement of the test apparatus must 
include the components described in this section. Minor details of the 
apparatus may vary, depending on the model of the burner used.

[[Page 256]]

    (1) Specimen Mounting Stand. The mounting stand for the test 
specimens consists of steel angles.
    (2) Test Burner. The burner to be used in tesing must--
    (i) Be a modified gun type.
    (ii) Use a suitable nozzle and maintain fuel pressure to yield a 2 
GPH fuel flow. For example: An 80 degree nozzle nominally rated at 2.25 
GPH and operated at 85 pounds per square inch (PSI) gauge to deliver 
2.03 GPH.
    (iii) Have a 12 inch (305 mm) burner extension installed at the end 
of the draft tube with an opening 6 inches (152 mm) high and 11 inches 
(280 mm) wide.
    (iv) Have a burner fuel pressure regulator that is adjusted to 
deliver a nominal 2.0 GPH of 2 Grade kerosene or equivalent.
    Burner models which have been used successfully in testing are the 
Lenox Model OB-32, Carlin Model 200 CRD and Park Model DPL.
    (3) Calorimeter. (i) The calorimeter to be used in testing must be a 
total heat flux Foil Type Gardon Gage of an appropriate range 
(approximately 0 to 15.0 British thermal unit (BTU) per ft.\2\ sec., 0-
17.0 watts/cm\2\). The calorimeter must be mounted in a 6 inch by 12 
inch (152 by 305 mm) by \3/4\ inch (19 mm) thick insulating block which 
is attached to a steel angle bracket for placement in the test stand 
during burner calibration as shown in Figure 2 of this part of this 
appendix.
    (ii) The insulating block must be monitored for deterioration and 
the mounting shimmed as necessary to ensure that the calorimeter face is 
parallel to the exit plane of the test burner cone.
    (4) Thermocouples. The seven thermocouples to be used for testing 
must be \1/16\ inch ceramic sheathed, type K, grounded thermocouples 
with a nominal 30 American wire gage (AWG) size conductor. The seven 
thermocouples must be attached to a steel angle bracket to form a 
thermocouple rake for placement in the test stand during burner 
calibration.
    (5) Apparatus Arrangement. The test burner must be mounted on a 
suitable stand to position the exit of the burner cone a distance of 8 
inches from the ceiling liner panel and 2 inches from the sidewall liner 
panel. The burner stand should have the capability of allowing the 
burner to be swung away from the test specimen during warm-up periods.
    (6) Instrumentation. A recording potentiometer or other suitable 
instrument with an appropriate range must be used to measure and record 
the outputs of the calorimeter and the thermocouples.
    (7) Timing Device. A stopwatch or other device must be used to 
measure the time of flame application and the time of flame penetration, 
if it occurs.
    (e) Preparation of Apparatus. Before calibration, all equipment must 
be turned on and allowed to stabilize, and the burner fuel flow must be 
adjusted as specified in paragraph (d)(2).
    (f) Calibration. To ensure the proper thermal output of the burner 
the following test must be made:
    (1) Remove the burner extension from the end of the draft tube. Turn 
on the blower portion of the burner without turning the fuel or igniters 
on. Measure the air velocity using a hot wire anemometer in the center 
of the draft tube across the face of the opening. Adjust the damper such 
that the air velocity is in the range of 1550 to 1800 ft./min. If tabs 
are being used at the exit of the draft tube, they must be removed prior 
to this measurement. Reinstall the draft tube extension cone.
    (2) Place the calorimeter on the test stand as shown in Figure 2 at 
a distance of 8 inches (203 mm) from the exit of the burner cone to 
simulate the position of the horizontal test specimen.
    (3) Turn on the burner, allow it to run for 2 minutes for warm-up, 
and adjust the damper to produce a calorimeter reading of 8.0 0.5 BTU per ft.\2\ sec. (9.1 0.6 
Watts/cm\2\).
    (4) Replace the calorimeter with the thermocouple rake.
    (5) Turn on the burner and ensure that each of the seven 
thermocouples reads 1700 [deg]F. 100 [deg]F. (927 
[deg]C. 38 [deg]C.) to ensure steady state 
conditions have been achieved. If the temperature is out of this range, 
repeat steps 2 through 5 until proper readings are obtained.
    (6) Turn off the burner and remove the thermocouple rake.
    (7) Repeat (1) to ensure that the burner is in the correct range.
    (g) Test Procedure. (1) Mount a thermocouple of the same type as 
that used for calibration at a distance of 4 inches (102 mm) above the 
horizontal (ceiling) test specimen. The thermocouple should be centered 
over the burner cone.
    (2) Mount the test specimen on the test stand shown in Figure 1 in 
either the horizontal or vertical position. Mount the insulating 
material in the other position.
    (3) Position the burner so that flames will not impinge on the 
specimen, turn the burner on, and allow it to run for 2 minutes. Rotate 
the burner to apply the flame to the specimen and simultaneously start 
the timing device.
    (4) Expose the test specimen to the flame for 5 minutes and then 
turn off the burner. The test may be terminated earlier if flame 
penetration is observed.
    (5) When testing ceiling liner panels, record the peak temperature 
measured 4 inches above the sample.
    (6) Record the time at which flame penetration occurs if applicable.
    (h) Test Report. The test report must include the following:

[[Page 257]]

    (1) A complete description of the materials tested including type, 
manufacturer, thickness, and other appropriate data.
    (2) Observations of the behavior of the test specimens during flame 
exposure such as delamination, resin ignition, smoke, etc., including 
the time of such occurrence.
    (3) The time at which flame penetration occurs, if applicable, for 
each of the three specimens tested.

[72FR55099, Sept. 28, 2007]



PART 179_SPECIFICATIONS FOR TANK CARS--Table of Contents



              Subpart A_Introduction, Approvals and Reports

Sec.
179.1 General.
179.2 Definitions and abbreviations.
179.3 Procedure for securing approval.
179.4 Changes in specifications for tank cars.
179.5 Certificate of construction.
179.6 Repairs and alterations.
179.7 Quality assurance program.
179.8 Limitation on actions by states, local governments, and Indian 
          tribes.

                  Subpart B_General Design Requirements

179.10 Tank mounting.
179.11 Welding certification.
179.12 Interior heater systems.
179.13 Tank car capacity and gross weight limitation.
179.14 Coupler vertical restraint system.
179.15 Pressure relief devices.
179.16 Tank-head puncture-resistance systems.
179.18 Thermal protection systems.
179.20 Service equipment; protection systems.
179.22 Marking.
179.24 Stamping.

 Subpart C_Specifications for Pressure Tank Car Tanks (Classes DOT-105, 
                         109, 112, 114, and 120)

179.100 General specifications applicable to pressure tank car tanks.
179.100-1 Tanks built under these specifications shall comply with the 
          requirements of Sec. Sec. 179.100, 179.101 and when 
          applicable, Sec. Sec. 179.102 and 179.103.
179.100-3 Type.
179.100-4 Insulation.
179.100-6 Thickness of plates.
179.100-7 Materials.
179.100-8 Tank heads.
179.100-9 Welding.
179.100-10 Postweld heat treatment.
179.100-12 Manway nozzle, cover and protective housing.
179.100-13 Venting, loading and unloading valves, measuring and sampling 
          devices.
179.100-14 Bottom outlets.
179.100-16 Attachments.
179.100-17 Closures for openings.
179.100-18 Tests of tanks.
179.100-19 Tests of safety relief valves.
179.100-20 Stamping.
179.101 Individual specification requirements applicable to pressure 
          tank car tanks.
179.101-1 Individual specification requirements.
179.102 Special commodity requirements for pressure tank car tanks.
179.102-1 Carbon dioxide, refrigerated liquid.
179.102-2 Chlorine.
179.102-3 Materials poisonous by inhalation.
179.102-4 Vinyl fluoride, stabilized.
179.102-17 Hydrogen chloride, refrigerated liquid.
179.103 Special requirements for class 114A * * * tank car tanks.
179.103-1 Type.
179.103-2 Manway cover.
179.103-3 Venting, loading and unloading valves, measuring and sampling 
          devices.
179.103-4 Safety relief devices and pressure regulators.
179.103-5 Bottom outlets.

  Subpart D_Specifications for Nonpressure Tank Car Tanks (Classes DOT-
                            111AW and 115AW)

179.200 General specifications applicable to non-pressure tank car tanks 
          (Class DOT 111).
179.200-1 Tank built under these specifications must meet the 
          requirements of Sec. Sec. 179.200, and 179.201.
179.200-3 Type.
179.200-4 Insulation.
179.200-6 Thickness of plates.
179.200-7 Materials.
179.200-8 Tank heads.
179.200-9 Compartment tanks.
179.200-10 Welding.
179.200-11 Postweld heat treatment.
179.200-13 Manway ring or flange, pressure relief device flange, bottom 
          outlet nozzle flange, bottom washout nozzle flange and other 
          attachments and openings.
179.200-14 Expansion capacity.
179.200-15 Closures for manways.
179.200-16 Gauging devices, top loading and unloading devices, venting 
          and air inlet devices.
179.200-17 Bottom outlets.
179.200-19 Reinforcements, when used, and appurtenances not otherwise 
          specified.
179.200-21 Closures for openings.
179.200-22 Test of tanks.
179.200-23 Tests of pressure relief valves.
179.200-24 Stamping.

[[Page 258]]

179.201 Individual specification requirements applicable to non-pressure 
          tank car tanks.
179.201-1 Individual specification requirements.
179.201-2 [Reserved]
179.201-3 Lined tanks.
179.201-4 Material.
179.201-5 Postweld heat treatment and corrosion resistance.
179.201-6 Manways and manway closures.
179.201-8 Sampling device and thermometer well.
179.201-9 Gauging device.
179.201-10 Water capacity marking.
179.201-11 Insulation.
179.202--179.202-22 [Reserved]
179.220 General specifications applicable to nonpressure tank car tanks 
          consisting of an inner container supported within an outer 
          shell (class DOT-115).
179.220-1 Tanks built under these specifications must meet the 
          requirements of Sec. Sec. 179.220 and 179.221.
179.220-3 Type.
179.220-4 Insulation.
179.220-6 Thickness of plates.
179.220-7 Materials.
179.220-8 Tank heads.
179.220-9 Compartment tanks.
179.220-10 Welding.
179.220-11 Postweld heat treatment.
179.220-13 Inner container manway nozzle and cover.
179.220-14 Openings in the tanks.
179.220-15 Support system for inner container.
179.220-16 Expansion capacity.
179.220-17 Gauging devices, top loading and unloading devices, venting 
          and air inlet devices.
179.220-18 Bottom outlets.
179.220-20 Reinforcements, when used, and appurtenances not otherwise 
          specified.
179.220-22 Closure for openings.
179.220-23 Test of tanks.
179.220-24 Tests of pressure relief valves.
179.220-25 Stamping.
179.220-26 Stenciling.
179.221 Individual specification requirements applicable to tank car 
          tanks consisting of an inner container supported within an 
          outer shell.
179.221-1 Individual specification requirements.

Subpart E_Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A 
                               and 110AW)

179.300 General specifications applicable to multi-unit tank car tanks 
          designed to be removed from car structure for filling and 
          emptying (Classes DOT-106A and 110AW).
179.300-1 Tanks built under these specifications shall meet the 
          requirements of Sec. Sec. 179.300 and 179.301.
179.300-3 Type and general requirements.
179.300-4 Insulation.
179.300-6 Thickness of plates.
179.300-7 Materials.
179.300-8 Tank heads.
179.300-9 Welding.
179.300-10 Postweld heat treatment.
179.300-12 Protection of fittings.
179.300-13 Venting, loading and unloading valves.
179.300-14 Attachments not otherwise specified.
179.300-15 Pressure relief devices.
179.300-16 Tests of tanks.
179.300-17 Tests of pressure relief devices.
179.300-18 Stamping.
179.300-19 Inspection.
179.300-20 Reports.
179.301 Individual specification requirements for multi-unit tank car 
          tanks.
179.302 [Reserved]

Subpart F_Specification for Cryogenic Liquid Tank Car Tanks and Seamless 
                 Steel Tanks (Classes DOT-113 and 107A)

179.400 General specification applicable to cryogenic liquid tank car 
          tanks.
179.400-1 General.
179.400-3 Type.
179.400-4 Insulation system and performance standard.
179.400-5 Materials.
179.400-6 Bursting and buckling pressure.
179.400-7 Tank heads.
179.400-8 Thickness of plates.
179.400-9 Stiffening rings.
179.400-10 Sump or siphon bowl.
179.400-11 Welding.
179.400-12 Postweld heat treatment.
179.400-13 Support system for inner tank.
179.400-14 Cleaning of inner tank.
179.400-15 Radioscopy.
179.400-16 Access to inner tank.
179.400-17 Inner tank piping.
179.400-18 Test of inner tank.
179.400-19 Valves and gages.
179.400-20 Pressure relief devices.
179.400-21 Test of pressure relief valves.
179.400-22 Protective housings.
179.400-23 Operating instructions.
179.400-24 Stamping.
179.400-25 Stenciling.
179.401 Individual specification requirements applicable to inner tanks 
          for cryogenic liquid tank car tanks.
179.401-1 Individual specification requirements.
179.500 Specification DOT-107A * * * *, seamless steel tank car tanks.
179.500-1 Tanks built under these specifications shall meet the 
          requirements of Sec. 179.500.
179.500-3 Type and general requirements.

[[Page 259]]

179.500-4 Thickness of wall.
179.500-5 Material.
179.500-6 Heat treatment.
179.500-7 Physical tests.
179.500-8 Openings in tanks.
179.500-10 Protective housing.
179.500-11 Loading and unloading valves.
179.500-12 Pressure relief devices.
179.500-13 Fixtures.
179.500-14 Test of tanks.
179.500-15 Handling of tanks failing in tests.
179.500-16 Tests of pressure relief devices.
179.500-17 Marking.
179.500-18 Inspection and reports.

Appendix A to Part 179--Procedures for Tank-Head Puncture-Resistance 
          Test
Appendix B to Part 179--Procedures for Simulated Pool and Torch-Fire 
          Testing

    Authority:  49 U.S.C. 5101-5128; 49 CFR 1.53.

    Source: 29 FR 18995, Dec. 29, 1964, unless otherwise noted. 
Redesignated at 32 FR 5606, Apr. 5, 1967.



              Subpart A_Introduction, Approvals and Reports



Sec. 179.1  General.

    (a) This part prescribes the specifications for tanks that are to be 
mounted on or form part of a tank car and which are to be marked with a 
DOT specification.
    (b) Except as provided in paragraph (c) of this section, tanks to 
which this part is applicable, must be built to the specifications 
prescribed in this part.
    (c) Tanks built to specifications predating those in this part may 
continue in use as provided in Sec. 180.507 of this subchapter.
    (d) Any person who performs a function prescribed in this part, 
shall perform that function in accordance with this part.
    (e) When this part requires a tank to be marked with a DOT 
specification (for example, DOT-105A100W), compliance with that 
requirement is the responsibility of the tank builder. Marking the tank 
with the DOT specification shall be understood to certify compliance by 
the builder that the functions performed by the builder, as prescribed 
in this part, have been performed in compliance with this part.
    (f) The tank builder should inform each person to whom that tank is 
transferred of any specification requirements which have not been met at 
time of transfer.

[Amdt. 179-17, 41 FR 38183, Sept. 9, 1976, as amended by Amdt. 179-50, 
60 FR 49076, Sept. 21, 1995; 68 FR 48571, Aug. 14, 2003]



Sec. 179.2  Definitions and abbreviations.

    (a) The following apply in part 179:
    (1) AAR means Association of American Railroads.
    (2) Approved means approval by the AAR Tank Car Committee.
    (3) ASTM means American Society for Testing and Materials.
    (4) [Reserved]
    (5) Definitions in part 173 of this chapter also apply.
    (6) F means degrees Fahrenheit.
    (7) NGT means National Gas Taper Threads.
    (8) NPT means an American Standard Taper Pipe Thread conforming to 
the requirements of NBS Handbook H-28 (IBR, see Sec. 171.7 of this 
subchapter).
    (9) [Reserved]
    (10) Tank car facility means an entity that manufactures, repairs, 
inspects, tests, qualifies, or maintains a tank car to ensure that the 
tank car conforms to this part and subpart F of part 180 of this 
subchapter, that alters the certificate of construction of the tank car, 
that ensures the continuing qualification of a tank car by performing a 
function prescribed in parts 179 or 180 of this subchapter, or that 
makes any representation indicating compliance with one or more of the 
requirements of parts 179 or 180 of this subchapter.
    (11) Tanks means tank car tanks.
    (b) [Reserved]

[29 FR 18995, Dec. 20, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 179-10, 36 FR 21344, Nov. 6, 1971; Amdt. 179-50, 60 
FR 49076, Sept. 21, 1995; Amdt. 179-50, 61 FR 33255, June 26, 1996; 63 
FR 52850, Oct. 1, 1998; 66 FR 45186, 45390, Aug. 28, 2001; 68 fR 75759, 
Dec. 31, 2003]



Sec. 179.3  Procedure for securing approval.

    (a) Application for approval of designs, materials and construction, 
conversion or alteration of tank car tanks under these specifications, 
complete with detailed prints, must be submitted in prescribed form to 
the Executive Director--Tank Car Safety, AAR,

[[Page 260]]

for consideration by its Tank Car Committee and other appropriate 
committees. Approval or rejections of applications based on appropriate 
committee action will be issued by the executive director.
    (b) When, in the opinion of the Committee, such tanks or equipment 
are in compliance with the requirements of this subchapter, the 
application will be approved.
    (c) When such tanks or equipment are not in compliance with the 
requirements of this subchapter, the Committee may recommend service 
trials to determine the merits of a change in specifications. Such 
service trials may be conducted only if the builder or shipper applies 
for and obtains a special permit.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967 
and amended by Amdt. 179-41, 52 FR 36672, Sept. 30, 1987; 63 FR 52850, 
Oct. 1, 1998; 68 FR 48571, Aug. 14, 2003; 70 FR 73166, Dec. 9, 2005]



Sec. 179.4  Changes in specifications for tank cars.

    (a) Proposed changes in or additions to specifications for tanks 
must be submitted to the Executive Director--Tank Car Safety, AAR, for 
consideration by its Tank Car Committee. An application for construction 
of tanks to any new specification may be submitted with proposed 
specification. Construction should not be started until the 
specification has been approved or a special permit has been issued. 
When proposing a new specification, the applicant shall furnish 
information to justify a new specification. This data should include the 
properties of the lading and the method of loading and unloading.
    (b) The Tank Car Committee will review the proposed specifications 
at its earliest convenience and report its recommendations through the 
Executive Director--Tank Car Safety to the Department. The 
recommendation will be considered by the Department in determining 
appropriate action.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967 
and amended by Amdt. 179-41, 52 FR 36672, Sept. 30, 1987; 63 FR 52850, 
Oct. 1, 1998; 70 FR 73166, Dec. 9, 2005]



Sec. 179.5  Certificate of construction.

    (a) Before a tank car is placed in service, the party assembling the 
completed car shall furnish a Certificate of Construction, Form AAR 4-2 
to the owner and the Executive Director--Tank Car Safety, AAR, 
certifying that the tank, equipment, and car fully conforms to all 
requirements of the specification.
    (b) When cars or tanks are covered in one application and are 
identical in all details are built in series, one certificate will 
suffice for each series when submitted to the Executive Director--Tank 
Car Safety, AAR.
    (c) If the owner elects to furnish service equipment, the owner 
shall furnish the Executive Director--Tank Car Safety, AAR, a report in 
prescribed form, certifying that the service equipment complies with all 
the requirements of the specifications.
    (d) When cars or tanks which are covered on one application and are 
identical in all details are built in series, one certificate shall 
suffice for each series when submitted to the Executive Director--Tank 
Car Safety, AAR. One copy of the Certificate of Construction must be 
furnished to the Executive Director--Tank Car Safety, AAR for each car 
number of consecutively numbered group or groups covered by the original 
application.

[Amdt. 179-10, 36 FR 21344, Nov. 6, 1971, as amended at 63 FR 52850, 
Oct. 1, 1998; 68 FR 48571, Aug. 14, 2003]



Sec. 179.6  Repairs and alterations.

    For procedure to be followed in making repairs or alterations, see 
appendix R of the AAR Specifications for Tank Cars (IBR, see Sec. 171.7 
of this subchapter).

[68 FR 75759, Dec. 31, 2003]



Sec. 179.7  Quality assurance program.

    (a) At a minimum, each tank car facility shall have a quality 
assurance program, approved by AAR, that--
    (1) Ensures the finished product conforms to the requirements of the 
applicable specification and regulations of this subchapter;

[[Page 261]]

    (2) Has the means to detect any nonconformity in the manufacturing, 
repair, inspection, testing, and qualification or maintenance program of 
the tank car; and
    (3) Prevents non-conformities from recurring.
    (b) At a minimum, the quality assurance program must have the 
following elements
    (1) Statement of authority and responsibility for those persons in 
charge of the quality assurance program.
    (2) An organizational chart showing the interrelationship between 
managers, engineers, purchasing, construction, inspection, testing, and 
quality control personnel.
    (3) Procedures to ensure that the latest applicable drawings, design 
calculations, specifications, and instructions are used in manufacture, 
inspection, testing, and repair.
    (4) Procedures to ensure that the fabrication and construction 
materials received are properly identified and documented.
    (5) A description of the manufacturing, repair, inspection, testing, 
and qualification or maintenance program, including the acceptance 
criteria, so that an inspector can identify the characteristics of the 
tank car and the elements to inspect, examine, and test at each point.
    (6) Monitoring and control of processes and product characteristics 
during production.
    (7) Procedures for correction of nonconformities.
    (8) Provisions indicating that the requirements of the AAR 
Specifications for Tank Cars (IBR, see Sec. 171.7 of this subchapter), 
apply.
    (9) Qualification requirements of personnel performing non-
destructive inspections and tests.
    (10) Procedures for evaluating the inspection and test technique 
employed, including the accessibility of the area and the sensitivity 
and reliability of the inspection and test technique and minimum 
detectable crack length.
    (11) Procedures for the periodic calibration and measurement of 
inspection and test equipment.
    (12) A system for the maintenance of records, inspections, tests, 
and the interpretation of inspection and test results.
    (c) Each tank car facility shall ensure that only personnel 
qualified for each non-destructive inspection and test perform that 
particular operation.
    (d) Each tank car facility shall provide written procedures to its 
employees to ensure that the work on the tank car conforms to the 
specification, AAR approval, and owner's acceptance criteria.
    (e) Each