[Title 29 CFR ]
[Code of Federal Regulations (annual edition) - July 1, 2000 Edition]
[From the U.S. Government Printing Office]
29
Labor
[[Page i]]
PART 1910 (Sec. 1910.1000 to END)
Revised as of July 1, 1999
CONTAINING
A CODIFICATION OF DOCUMENTS
OF GENERAL APPLICABILITY
AND FUTURE EFFECT
AS OF JULY 1, 1999
With Ancillaries
Published by
the Office of the Federal Register
National Archives and Records
Administration
as a Special Edition of
the Federal Register
[[Page ii]]
U.S. GOVERNMENT PRINTING OFFICE
WASHINGTON : 1999
For sale by U.S. Government Printing Office
Superintendent of Documents, Mail Stop: SSOP, Washington, DC 20402-9328
[[Page iii]]
Table of Contents
Page
Explanation................................................. v
Title 29:
Subtitle B--Regulations Relating to Labor (Continued):
Chapter XVII--Occupational Safety and Health
Administration, Department of Labor................. 5
Finding Aids:
Material Approved for Incorporation by Reference........ 541
Table of CFR Titles and Chapters........................ 543
Alphabetical List of Agencies Appearing in the CFR...... 561
Table of OMB Control Numbers............................ 571
List of CFR Sections Affected........................... 573
[[Page iv]]
----------------------------
Cite this Code: CFR
To cite the regulations in
this volume use title,
part and section number.
Thus, 29 CFR 1910.1000
refers to title 29, part
1910, section 1000.
----------------------------
[[Page v]]
EXPLANATION
The Code of Federal Regulations is a codification of the general and
permanent rules published in the Federal Register by the Executive
departments and agencies of the Federal Government. The Code is divided
into 50 titles which represent broad areas subject to Federal
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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
volume.
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EFFECTIVE AND EXPIRATION DATES
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OMB CONTROL NUMBERS
The Paperwork Reduction Act of 1980 (Pub. L. 96-511) requires
Federal agencies to display an OMB control number with their information
collection request.
[[Page vi]]
Many agencies have begun publishing numerous OMB control numbers as
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OBSOLETE PROVISIONS
Provisions that become obsolete before the revision date stated on
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INCORPORATION BY REFERENCE
What is incorporation by reference? Incorporation by reference was
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This material, like any other properly issued regulation, has the force
of law.
What is a proper incorporation by reference? The Director of the
Federal Register will approve an incorporation by reference only when
the requirements of 1 CFR part 51 are met. Some of the elements on which
approval is based are:
(a) The incorporation will substantially reduce the volume of
material published in the Federal Register.
(b) The matter incorporated is in fact available to the extent
necessary to afford fairness and uniformity in the administrative
process.
(c) The incorporating document is drafted and submitted for
publication in accordance with 1 CFR part 51.
Properly approved incorporations by reference in this volume are
listed in the Finding Aids at the end of this volume.
What if the material incorporated by reference cannot be found? If
you have any problem locating or obtaining a copy of material listed in
the Finding Aids of this volume as an approved incorporation by
reference, please contact the agency that issued the regulation
containing that incorporation. If, after contacting the agency, you find
the material is not available, please notify the Director of the Federal
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20408, or call (202) 523-4534.
CFR INDEXES AND TABULAR GUIDES
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Authorities and Agency Rules (Table I). A list of CFR titles, chapters,
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The Federal Register Index is issued monthly in cumulative form.
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the daily Federal Register.
A List of CFR Sections Affected (LSA) is published monthly, keyed to
the revision dates of the 50 CFR titles.
[[Page vii]]
REPUBLICATION OF MATERIAL
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in the Code of Federal Regulations.
INQUIRIES
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Raymond A. Mosley,
Director,
Office of the Federal Register.
July 1, 1999.
[[Page ix]]
THIS TITLE
Title 29--Labor is composed of nine volumes. The parts in these
volumes are arranged in the following order: parts 0-99, parts 100-499,
parts 500-899, parts 900-1899, parts 1900-1910.999, part 1910.1000-End,
parts 1911-1925, part 1926, and part 1927 to end. The contents of these
volumes represent all current regulations codified under this title as
of July 1, 1999.
The OMB control numbers for title 29 CFR part 1910 appear in
Sec. 1910.8. For the convenience of the user, Sec. 1910.8 appears in the
Finding Aids section of the volume containing Sec. 1910.1000 to the end.
Redesignation tables appear in the Finding Aids section of the
eighth volume.
Subject indexes appear following the occupational safety and health
standards (part 1910), and following the safety and health regulations
for: Longshoring (part 1918), Gear Certification (part 1919), and
Construction (part 1926).
For this volume, Shelley C. Featherson was Chief Editor. The Code of
Federal Regulations publication program is under the direction of
Frances D. McDonald, assisted by Alomha S. Morris.
[[Page x]]
[[Page 1]]
TITLE 29--LABOR
(This book contains Part 1910 (Sec. 1910.1000 to End))
--------------------------------------------------------------------
SUBTITLE B--Regulations Relating to Labor (Continued)
Part
Chapter XVII--Occupational Safety and Health Administration,
Department of Labor....................................... 1910
Cross references: Railroad Retirement Board: See Employees' Benefits, 20
CFR Chapter II.
Social Security Administration, Department of Health and Human
Services: See Employees' Benefits, 20 CFR Chapter III.
Editorial Note: Other regulations issued by the Department of Labor
appear in 20 CFR Chapters I, IV, V, VI, VII and IX; 29 CFR Subtitle A,
Chapters II, IV, V, XXV; 30 CFR Chapter I; 41 CFR Chapters 50, 60, and
61; 48 CFR Chapter 29. For Standards for a Merit System of Personnel
Administration: See 5 CFR Part 900.
[[Page 3]]
Subtitle B--Regulations Relating to Labor (Continued)
[[Page 5]]
CHAPTER XVII--OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION,
DEPARTMENT OF LABOR (Continued)
--------------------------------------------------------------------
Editorial Note: Chapter XVII is continued in the volumes containing 29
CFR Parts 1911 to 1925, Part 1926, and Part 1927 to End.
Part Page
1910 Occupational safety and health standards
(continued)............................. 7
Subject index for 29 CFR part 1910--
Occupational safety and health standards 499
[[Page 7]]
PART 1910--OCCUPATIONAL SAFETY AND HEALTH STANDARDS (Continued)--Table of Contents
Subpart Z--Toxic and Hazardous Substances
Sec.
1910.1000 Air contaminants.
1910.1001 Asbestos.
1910.1002 Coal tar pitch volatiles; interpretation of term.
1910.1003 13 Carcinogens (4-Nitrobiphenyl, etc.).
1910.1004 alpha-Naphthylamine.
1910.1005 [Reserved]
1910.1006 Methyl chloromethyl ether.
1910.1007 3,'--Dichlorobenzidine (and its salts).
1910.1008 bis-Chloromethyl ether.
1910.1009 beta-Naphthylamine.
1910.1010 Benzidine.
1910.1011 4-Aminodiphenyl.
1910.1012 Ethyleneimine.
1910.1013 beta-Propiolactone.
1910.1014 2-Acetylaminofluorene.
1910.1015 4-Dimethylaminoazobenzene.
1910.1016 N-Nitrosodimethylamine.
1910.1017 Vinyl chloride.
1910.1018 Inorganic arsenic.
1910.1020 Access to employee exposure and medical records.
1910.1025 Lead.
1910.1027 Cadmium.
1910.1028 Benzene.
1910.1029 Coke oven emissions.
1910.1030 Bloodborne pathogens.
1910.1043 Cotton dust.
1910.1044 1,2-dibromo-3-chloropropane.
1910.1045 Acrylonitrile.
1910.1047 Ethylene oxide.
1910.1048 Formaldehyde.
1910.1050 Methylenedianiline.
1910.1051 1,3-Butadiene.
1910.1052 Methylene Chloride.
1910.1096 Ionizing radiation.
1910.1200 Hazard communication.
1910.1201 Retention of DOT markings, placards and labels.
1910.1450 Occupational exposure to hazardous chemicals in laboratories.
Subject Index for 29 CFR Part 1910--Occupational Safety and Health
Standards
Subpart Z--Toxic and Hazardous Substances
Authority: Sections 4, 6, and 8 of the Occupational Safety and
Health Act of 1970 (29 U.S.C. 653, 655, 657); Secretary of Labor's Order
No. 12-71 (36 FR 8754), 8-76 (41 FR 25059), 9-83 (48 FR 35736), or 6-96
(62 FR 111), as applicable; and 29 CFR part 1911.
All of subpart Z issued under sec. 6(b) of the Occupational Safety
and Health Act, except those substances that have exposure limits listed
in Tables Z-1, Z-2, and Z-3 of 29 CFR 1910.1000. The latter were issued
under sec. 6(a) (29 U.S.C. 655(a)).
Section 1910.1000, Tables Z-1, Z-2 and Z-3 also issued under 5
U.S.C. 553, Section 1910.1000 Tables Z-1, Z-2, and Z-3 not issued under
29 CFR part 1911 except for the arsenic (organic compounds), benzene,
and cotton dust listings.
Section 1910.1001 also issued under section 107 of the Contract Work
Hours and Safety Standards Act (40 U.S.C. 333) and 5 U.S.C. 553.
Section 1910.1002 not issued under 29 U.S.C. 655 or 29 CFR part
1911; also issued under 5 U.S.C. 553.
Sections 1910.1018, 1910.1029 and 1910.1200 are also issued under 29
U.S.C. 653.
Source: 39 FR 23502, June 27, 1974, unless otherwise noted.
Redesignated at 40 FR 23072, May 28, 1975.
Sec. 1910.1000 Air contaminants.
An employee's exposure to any substance listed in Tables Z-1, Z-2,
or Z-3 of this section shall be limited in accordance with the
requirements of the following paragraphs of this section.
(a) Table Z-1--(1) Substances with limits preceded by ``C''--Ceiling
Values. An employee's exposure to any substance in Table Z-1, the
exposure limit of which is preceded by a ``C'', shall at no time exceed
the exposure limit given for that substance. If instantaneous monitoring
is not feasible, then the ceiling shall be assessed as a 15-minute time
weighted average exposure which shall not be exceeded at any time during
the working day.
(2) Other substances--8-hour Time Weighted Averages. An employee's
exposure to any substance in Table Z-1, the exposure limit of which is
not preceded by a ``C'', shall not exceed the 8-hour Time Weighted
Average given for that substance in any 8-hour work shift of a 40-hour
work week.
(b) Table Z-2. An employee's exposure to any substance listed in
Table Z-2 shall not exceed the exposure limits specified as follows:
(1) 8-hour time weighted averages. An employee's exposure to any
substance listed in Table Z-2, in any 8-hour work shift of a 40-hour
work week, shall not exceed the 8-hour time weighted average limit given
for that substance in Table Z-2.
[[Page 8]]
(2) Acceptable ceiling concentrations. An employee's exposure to a
substance listed in Table Z-2 shall not exceed at any time during an 8-
hour shift the acceptable ceiling concentration limit given for the
substance in the table, except for a time period, and up to a
concentration not exceeding the maximum duration and concentration
allowed in the column under ``acceptable maximum peak above the
acceptable ceiling concentration for an 8-hour shift.''
(3) Example. During an 8-hour work shift, an employee may be exposed
to a concentration of Substance A (with a 10 ppm TWA, 25 ppm ceiling and
50 ppm peak) above 25 ppm (but never above 50 ppm) only for a maximum
period of 10 minutes. Such exposure must be compensated by exposures to
concentrations less than 10 ppm so that the cumulative exposure for the
entire 8-hour work shift does not exceed a weighted average of 10 ppm.
(c) Table Z-3. An employee's exposure to any substance listed in
Table Z-3, in any 8-hour work shift of a 40-hour work week, shall not
exceed the 8-hour time weighted average limit given for that substance
in the table.
(d) Computation formulae. The computation formula which shall apply
to employee exposure to more than one substance for which 8-hour time
weighted averages are listed in subpart Z of 29 CFR part 1910 in order
to determine whether an employee is exposed over the regulatory limit is
as follows:
(1)(i) The cumulative exposure for an 8-hour work shift shall be
computed as follows:
E = (Ca Ta+Cb Tb+. .
.Cn Tn)8
Where:
E is the equivalent exposure for the working shift.
C is the concentration during any period of time T where the
concentration remains constant.
T is the duration in hours of the exposure at the concentration C.
The value of E shall not exceed the 8-hour time weighted average
specified in subpart Z of 29 CFR part 1910 for the substance involved.
(ii) To illustrate the formula prescribed in paragraph (d)(1)(i) of
this section, assume that Substance A has an 8-hour time weighted
average limit of 100 ppm noted in Table Z-1. Assume that an employee is
subject to the following exposure:
Two hours exposure at 150 ppm
Two hours exposure at 75 ppm
Four hours exposure at 50 ppm
Substituting this information in the formula, we have
(2 x 150+2 x 75+4 x 50)8=81.25 ppm
Since 81.25 ppm is less than 100 ppm, the 8-hour time weighted
average limit, the exposure is acceptable.
(2)(i) In case of a mixture of air contaminants an employer shall
compute the equivalent exposure as follows:
Em=(C1L1+C2L2
)+. . .(CnLn)
Where:
Em is the equivalent exposure for the mixture.
C is the concentration of a particular contaminant.
L is the exposure limit for that substance specified in subpart Z of 29
CFR part 1910.
The value of Em shall not exceed unity (1).
(ii) To illustrate the formula prescribed in paragraph (d)(2)(i) of
this section, consider the following exposures:
------------------------------------------------------------------------
Actual
concentration
Substance of 8-hour 8-hour TWA
exposure PEL (ppm)
(ppm)
------------------------------------------------------------------------
B........................................... 500 1,000
C........................................... 45 200
D........................................... 40 200
------------------------------------------------------------------------
Substituting in the formula, we have:
Em=5001,000+45200+40200
Em=0.500+0.225+0.200
Em=0.925
Since Em is less than unity (1), the exposure combination is
within acceptable limits.
(e) To achieve compliance with paragraphs (a) through (d) of this
section, administrative or engineering controls must first be determined
and implemented whenever feasible. When such controls are not feasible
to achieve full compliance, protective equipment or any other protective
measures shall be used to keep the exposure of employees to air
contaminants within the limits prescribed in this section. Any equipment
and/or technical measures used for this purpose must be approved for
each particular use by a competent industrial hygienist or other
technically qualified person. Whenever respirators
[[Page 9]]
are used, their use shall comply with 1910.134.
(f) Effective dates. The exposure limits specified have been in
effect with the method of compliance specified in paragraph (e) of this
section since May 29, 1971.
Table Z-1--Limits for Air Contaminants
----------------------------------------------------------------------------------------------------------------
mg/m\3\ (b)
Substance CAS No. (c) ppm (a) \1\ \1\ Skin designation
----------------------------------------------------------------------------------------------------------------
Acetaldehyde.............................. 75-07-0 200 360 .........................
Acetic acid............................... 64-19-7 10 25 .........................
Acetic anhydride.......................... 108-24-7 5 20 .........................
Acetone................................... 67-64-1 1000 2400 .........................
Acetonitrile.............................. 75-05-8 40 70 .........................
2-Acetylaminofluorine; see 1910.1014...... 53-96-3
Acetylene dichloride; see 1,2-
Dichloroethylene.
Acetylene tetrabromide.................... 79-27-6 1 14 .........................
Acrolein.................................. 107-02-8 0.1 0.25 .........................
Acrylamide................................ 79-06-1 ............ 0.3 X
Acrylonitrile; see 1910.1045.............. 107-13-1
Aldrin.................................... 309-00-2 ............ 0.25 X
Allyl alcohol............................. 107-18-6 2 5 X
Allyl chloride............................ 107-05-1 1 3 .........................
Allyl glycidyl ether (AGE)................ 106-92-3 (C)10 (C)45 .........................
Allyl propyl disulfide.................... 2179-59-1 2 12 .........................
alpha-Alumina............................. 1344-28-1
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Aluminum, metal (as Al)................... 7429-90-5
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
4-Aminodiphenyl; see 1910.1011............ 92-67-1
2-Aminoethanol; see Ethanolamine.
2-Aminopyridine........................... 504-29-0 0.5 2 .........................
Ammonia................................... 7664-41-7 50 35 .........................
Ammonium sulfamate........................ 7773-06-0
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
n-Amyl acetate............................ 628-63-7 100 525 .........................
sec-Amyl acetate.......................... 626-38-0 125 650 .........................
Aniline and homologs...................... 62-53-3 5 19 X
Anisidine (o-, p-isomers)................. 29191-52-4 ............ 0.5 X
Antimony and compounds (as Sb)............ 7440-36-0 ............ 0.5 .........................
ANTU (alpha Naphthylthiourea)............. 86-88-4 ............ 0.3 .........................
Arsenic, inorganic compounds (as As); see 7440-38-2
1910.1018.
Arsenic, organic compounds (as As)........ 7440-38-2 ............ 0.5 .........................
Arsine.................................... 7784-42-1 0.05 0.2 .........................
Asbestos; see 1910.1001................... (\4\)
Azinphos-methyl........................... 86-50-0 ............ 0.2 X
Barium, soluble compounds (as Ba)......... 7440-39-3 ............ 0.5 .........................
Barium sulfate............................ 7727-43-7
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Benomyl................................... 17804-35-2
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Benzene; see 1910.1028.................... 71-43-2
See Table Z-2 for the limits
applicable in the operations or
sectors excluded in 1910.1028 d
Benzidine; see 1910.1010.................. 92-87-5
p-Benzoquinone; see Quinone.
Benzo(a)pyrene; see Coal tar pitch
volatiles..
Benzoyl peroxide.......................... 94-36-0 ............ 5 .........................
Benzyl chloride........................... 100-44-7 1 5 .........................
Beryllium and beryllium compounds (as Be). 7440-41-7 (\2\)
Biphenyl; see Diphenyl.
Bismuth telluride, Undoped................ 1304-82-1
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Boron oxide............................... 1303-86-2
Total dust............................ ............ 15 .........................
Boron trifluoride......................... 7637-07-2 (C)1 (C)3 .........................
Bromine................................... 7726-95-6 0.1 0.7 .........................
Bromoform................................. 75-25-2 0.5 5 X
[[Page 10]]
Butadiene (1,3-Butadiene); See 29 CFR 106-99-0 1 ppm/5 ppm ........... .........................
1910.1051; 29 CFR 1910.19(l). STEL
Butanethiol; see Butyl mercaptan.
2-Butanone (Methyl ethyl ketone).......... 78-93-3 200 590 .........................
2-Butoxyethanol........................... 111-76-2 50 240 X
n-Butyl-acetate........................... 123-86-4 150 710 .........................
sec-Butyl acetate......................... 105-46-4 200 950 .........................
tert-Butyl acetate........................ 540-88-5 200 950 .........................
n-Butyl alcohol........................... 71-36-3 100 300 .........................
sec-Butyl alcohol......................... 78-92-2 150 450 .........................
tert-Butyl alcohol........................ 75-65-0 100 300 .........................
Butylamine................................ 109-73-9 (C)5 (C)15 X
tert-Butyl chromate (as CrO3)............. 1189-85-1 ............ (C)0.1 X
n-Butyl glycidyl ether (BGE).............. 2426-08-6 50 270 .........................
Butyl mercaptan........................... 109-79-5 10 35 .........................
p-tert-Butyltoluene....................... 98-51-1 10 60 .........................
Cadmium (as Cd); see 1910.1027............ 7440-43-9
Calcium carbonate......................... 1317-65-3
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Calcium hydroxide......................... 1305-62-0
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Calcium oxide............................. 1305-78-8 ............ 5 .........................
Calcium silicate.......................... 1344-95-2
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Calcium sulfate........................... 7778-18-9
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Camphor, synthetic........................ 76-22-2 ............ 2 .........................
Carbaryl (Sevin).......................... 63-25-2 ............ 5 .........................
Carbon black.............................. 1333-86-4 ............ 3.5 .........................
Carbon dioxide............................ 124-38-9 5000 9000 .........................
Carbon disulfide.......................... 75-15-0 (\2\)
Carbon monoxide........................... 630-08-0 50 55 .........................
Carbon tetrachloride...................... 56-23-5 (\2\)
Cellulose................................. 9004-34-6
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Chlordane................................. 57-74-9 ............ 0.5 X
Chlorinated camphene...................... 8001-35-2 ............ 0.5 X
Chlorinated diphenyl oxide................ 55720-99-5 ............ 0.5 .........................
Chlorine.................................. 7782-50-5 (C)1 (C)3 .........................
Chlorine dioxide.......................... 10049-04-4 0.1 0.3 .........................
Chlorine trifluoride...................... 7790-91-2 (C)0.1 (C)0.4 .........................
Chloroacetaldehyde........................ 107-20-0 (C)1 (C)3 .........................
a-Chloroacetophenone (Phenacyl chloride).. 532-27-4 0.05 0.3 .........................
Chlorobenzene............................. 108-90-7 75 350 .........................
o-Chlorobenzylidene malononitrile......... 2698-41-1 0.05 0.4 .........................
Chlorobromomethane........................ 74-97-5 200 1050 .........................
2-Chloro-1,3-butadiene; see beta-
Chloroprene.
Chlorodiphenyl (42% Chlorine) (PCB)....... 53469-21-9 ............ 1 X
Chlorodiphenyl (54% Chlorine) (PCB)....... 11097-69-1 ............ 0.5 X
1-Chloro-2,3-epoxypropane; see
Epichlorohydrin.
2-Chloroethanol; see Ethylene
chlorohydrin.
Chloroethylene; see Vinyl chloride.
Chloroform (Trichloromethane)............. 67-66-3 (C)50 (C)240 .........................
bis(Chloromethyl) ether; see 1910.1008.... 542-88-1
Chloromethyl methyl ether; see 1910.1006.. 107-30-2
1-Chloro-1-nitropropane................... 600-25-9 20 100 .........................
Chloropicrin.............................. 76-06-2 0.1 0.7 .........................
beta-Chloroprene.......................... 126-99-8 25 90 X
2-Chloro-6-(trichloromethyl) pyridine..... 1929-82-4
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Chromic acid and chromates (as CrO3)...... (\4\) (\2\)
Chromium (II) compounds.
(as Cr)............................... 7440-47-3 ............ 0.5 .........................
Chromium (III) compounds.
(as Cr)............................... 7440-47-3 ............ 0.5 .........................
Chromium metal and insol. salts (as Cr)... 7440-47-3 ............ 1 .........................
[[Page 11]]
Chrysene; see Coal tar pitch volatiles.
Clopidol.................................. 2971-90-6
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Coal dust (less than 5% SiO2), respirable (\3\)
fraction.
Coal dust (greater than or equal to 5% (\3\)
SiO2), respirable fraction.
Coal tar pitch volatiles (benzene soluble 65966-93-2 ............ 0.2 .........................
fraction), anthracene, BaP, phenanthrene,
acridine, chrysene, pyrene.
Cobalt metal, dust, and fume (as Co)...... 7440-48-4 ............ 0.1 .........................
Coke oven emissions; see 1910.1029.
Copper.................................... 7440-50-8
Fume (as Cu).......................... ............ 0.1 .........................
Dusts and mists (as Cu)............... ............ 1 .........................
Cotton dust e; see 1910.1043.............. ............ 1
Crag herbicide (Sesone)................... 136-78-7
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Cresol, all isomers....................... 1319-77-3 5 22 X
Crotonaldehyde............................ 123-73-9; 2 6
4170-30-3
Cumene.................................... 98-82-8 50 245 X
Cyanides (as CN).......................... (\4\) ............ 5 X
Cyclohexane............................... 110-82-7 300 1050 .........................
Cyclohexanol.............................. 108-93-0 50 200 .........................
Cyclohexanone............................. 108-94-1 50 200 .........................
Cyclohexene............................... 110-83-8 300 1015 .........................
Cyclopentadiene........................... 542-92-7 75 200 .........................
2,4-D (Dichlorophenoxyacetic acid)........ 94-75-7 ............ 10 .........................
Decaborane................................ 17702-41-9 0.05 0.3 X
Demeton (Systox).......................... 8065-48-3 ............ 0.1 X
Diacetone alcohol (4-Hydroxy-4-methyl-2- 123-42-2 50 240 .........................
pentanone).
1,2-Diaminoethane; see Ethylenediamine.
Diazomethane.............................. 334-88-3 0.2 0.4 .........................
Diborane.................................. 19287-45-7 0.1 0.1 .........................
1,2-Dibromo-3-chloropropane (DBCP); see 96-12-8
1910.1044.
1,2-Dibromoethane; see Ethylene dibromide.
Dibutyl phosphate......................... 107-66-4 1 5 .........................
Dibutyl phthalate......................... 84-74-2 ............ 5 .........................
o-Dichlorobenzene......................... 95-50-1 (C)50 (C)300 .........................
p-Dichlorobenzene......................... 106-46-7 75 450 .........................
3,'-Dichlorobenzidine; see 1910.1007...... 91-94-1
Dichlorodifluoromethane................... 75-71-8 1000 4950 .........................
1,3-Dichloro-5,5-dimethyl hydantoin....... 118-52-5 ............ 0.2 .........................
Dichlorodiphenyltrichloroethane (DDT)..... 50-29-3 ............ 1 X
1,1-Dichloroethane........................ 75-34-3 100 400 .........................
1,2-Dichloroethane; see Ethylene
dichloride.
1,2-Dichloroethylene...................... 540-59-0 200 790 .........................
Dichloroethyl ether....................... 111-44-4 (C)15 (C)90 X
Dichloromethane; see Methylene chloride.
Dichloromonofluoromethane................. 75-43-4 1000 4200 .........................
1,1-Dichloro-1-nitroethane................ 594-72-9 (C)10 (C)60 .........................
1,2-Dichloropropane; see Propylene
dichloride.
Dichlorotetrafluoroethane................. 76-14-2 1000 7000 .........................
Dichlorvos (DDVP)......................... 62-73-7 ............ 1 X
Dicyclopentadienyl iron................... 102-54-5
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Dieldrin.................................. 60-57-1 ............ 0.25 X
Diethylamine.............................. 109-89-7 25 75 .........................
2-Diethylaminoethanol..................... 100-37-8 10 50 X
Diethyl ether; see Ethyl ether.
Difluorodibromomethane.................... 75-61-6 100 860 .........................
Diglycidyl ether (DGE).................... 2238-07-5 (C)0.5 (C)2.8 .........................
Dihydroxybenzene; see Hydroquinone.
Diisobutyl ketone......................... 108-83-8 50 290 .........................
Diisopropylamine.......................... 108-18-9 5 20 X
4-Dimethylaminoazobenzene; see 1910.1015.. 60-11-7
Dimethoxymethane; see Methylal.
Dimethyl acetamide........................ 127-19-5 10 35 X
Dimethylamine............................. 124-40-3 10 18 .........................
Dimethylaminobenzene; see Xylidine........
[[Page 12]]
Dimethylaniline (N,N-Dimethylaniline)..... 121-69-7 5 25 X
Dimethylbenzene; see Xylene.
Dimethyl-1,2-dibromo-2,2-dichloroethyl 300-76-5 ............ 3 .........................
phosphate.
Dimethylformamide......................... 68-12-2 10 30 X
2,6-Dimethyl-4-heptanone; see Diisobutyl
ketone.
1,1-Dimethylhydrazine..................... 57-14-7 0.5 1 X
Dimethylphthalate......................... 131-11-3 ............ 5 .........................
Dimethyl sulfate.......................... 77-78-1 1 5 X
Dinitrobenzene (all isomers).............. 1 X
(ortho)............................... 528-29-0
(meta)................................ 99-65-0
(para)................................ 100-25-4
Dinitro-o-cresol.......................... 534-52-1 ............ 0.2 X
Dinitrotoluene............................ 25321-14-6 ............ 1.5 X
Dioxane (Diethylene dioxide).............. 123-91-1 100 360 X
Diphenyl (Biphenyl)....................... 92-52-4 0.2 1 .........................
Diphenylmethane diisocyanate; see
Methylene bisphenyl isocyanate.
Dipropylene glycol methyl ether........... 34590-94-8 100 600 X
Di-sec octyl phthalate (Di-(2-ethylhexyl) 117-81-7 ............ 5 .........................
phthalate).
Emery..................................... 12415-34-8
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Endrin.................................... 72-20-8 ............ 0.1 X
Epichlorohydrin........................... 106-89-8 5 19 X
EPN....................................... 2104-64-5 ............ 0.5 X
1,2-Epoxypropane; see Propylene oxide.
2,3-Epoxy-1-propanol; see Glycidol.
Ethanethiol; see Ethyl mercaptan.
Ethanolamine.............................. 141-43-5 3 6 .........................
2-Ethoxyethanol (Cellosolve).............. 110-80-5 200 740 X
2-Ethoxyethyl acetate (Cellosolve acetate) 111-15-9 100 540 X
Ethyl acetate............................. 141-78-6 400 1400 .........................
Ethyl acrylate............................ 140-88-5 25 100 X
Ethyl alcohol (Ethanol)................... 64-17-5 1000 1900 .........................
Ethylamine................................ 75-04-7 10 18 .........................
Ethyl amyl ketone (5-Methyl-3-heptanone).. 541-85-5 25 130 .........................
Ethyl benzene............................. 100-41-4 100 435 .........................
Ethyl bromide............................. 74-96-4 200 890 .........................
Ethyl butyl ketone (3-Heptanone).......... 106-35-4 50 230 .........................
Ethyl chloride............................ 75-00-3 1000 2600 .........................
Ethyl ether............................... 60-29-7 400 1200 .........................
Ethyl formate............................. 109-94-4 100 300 .........................
Ethyl mercaptan........................... 75-08-1 (C)10 (C)25 .........................
Ethyl silicate............................ 78-10-4 100 850 .........................
Ethylene chlorohydrin..................... 107-07-3 5 16 X
Ethylenediamine........................... 107-15-3 10 25 .........................
Ethylene dibromide........................ 106-93-4 (\2\)
Ethylene dichloride (1,2-Dichloroethane).. 107-06-2 (\2\)
Ethylene glycol dinitrate................. 628-96-6 (C)0.2 (C)1 X
Ethylene glycol methyl acetate; see Methyl
cellosolve acetate.
Ethyleneimine; see 1910.1012.............. 151-56-4
Ethylene oxide; see 1910.1047............. 75-21-8
Ethylidene chloride; see 1,1-
Dichloroethane.
N-Ethylmorpholine......................... 100-74-3 20 94 X
Ferbam.................................... 14484-64-1
Total dust............................ ............ 15 .........................
Ferrovanadium dust........................ 12604-58-9 ............ 1 .........................
Fluorides (as F).......................... (\4\) ............ 2.5 .........................
Fluorine.................................. 7782-41-4 0.1 0.2 .........................
Fluorotrichloromethane 75-69-4 1000 5600 .........................
(Trichlorofluoromethane).
Formaldehyde; see 1910.1048............... 50-00-0
Formic acid............................... 64-18-6 5 9 .........................
Furfural.................................. 98-01-1 5 20 X
Furfuryl alcohol.......................... 98-00-0 50 200 .........................
Grain dust (oat, wheat, barley)........... .............. ............ 10 .........................
Glycerin (mist)........................... 56-81-5
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Glycidol.................................. 556-52-5 50 150 .........................
Glycol monoethyl ether; see 2-
Ethoxyethanol.
[[Page 13]]
Graphite, natural, respirable dust........ 7782-42-5 (\3\)
Graphite, synthetic.......................
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Guthion; see Azinphos methyl.
Gypsum.................................... 13397-24-5
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Hafnium................................... 7440-58-6 ............ 0.5 .........................
Heptachlor................................ 76-44-8 ............ 0.5 X
Heptane (n-Heptane)....................... 142-82-5 500 2000 .........................
Hexachloroethane.......................... 67-72-1 1 10 X
Hexachloronaphthalene..................... 1335-87-1 ............ 0.2 X
n-Hexane.................................. 110-54-3 500 1800 .........................
2-Hexanone (Methyl n-butyl ketone)........ 591-78-6 100 410 .........................
Hexone (Methyl isobutyl ketone)........... 108-10-1 100 410 .........................
sec-Hexyl acetate......................... 108-84-9 50 300 .........................
Hydrazine................................. 302-01-2 1 1.3 X
Hydrogen bromide.......................... 10035-10-6 3 10 .........................
Hydrogen chloride......................... 7647-01-0 (C)5 (C)7 .........................
Hydrogen cyanide.......................... 74-90-8 10 11 X
Hydrogen fluoride (as F).................. 7664-39-3 (\2\)
Hydrogen peroxide......................... 7722-84-1 1 1.4 .........................
Hydrogen selenide (as Se)................. 7783-07-5 0.05 0.2 .........................
Hydrogen sulfide.......................... 7783-06-4 (\2\)
Hydroquinone.............................. 123-31-9 ............ 2 .........................
Iodine.................................... 7553-56-2 (C)0.1 (C)1 .........................
Iron oxide fume........................... 1309-37-1 ............ 10 .........................
Isoamyl acetate........................... 123-92-2 100 525 .........................
Isoamyl alcohol (primary and secondary)... 123-51-3 100 360 .........................
Isobutyl acetate.......................... 110-19-0 150 700 .........................
Isobutyl alcohol.......................... 78-83-1 100 300 .........................
Isophorone................................ 78-59-1 25 140 .........................
Isopropyl acetate......................... 108-21-4 250 950 .........................
Isopropyl alcohol......................... 67-63-0 400 980 .........................
Isopropylamine............................ 75-31-0 5 12 .........................
Isopropyl ether........................... 108-20-3 500 2100 .........................
Isopropyl glycidyl ether (IGE)............ 4016-14-2 50 240 .........................
Kaolin.................................... 1332-58-7
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Ketene.................................... 463-51-4 0.5 0.9 .........................
Lead, inorganic (as Pb); see 1910.1025.... 7439-92-1
Limestone................................. 1317-65-3
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Lindane................................... 58-89-9 ............ 0.5 X
Lithium hydride........................... 7580-67-8 ............ 0.025 .........................
L.P.G. (Liquefied petroleum gas).......... 68476-85-7 1000 1800 .........................
Magnesite................................. 546-93-0
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Magnesium oxide fume...................... 1309-48-4
Total particulate..................... ............ 15 .........................
Malathion................................. 121-75-5
Total dust............................ ............ 15 X
Maleic anhydride.......................... 108-31-6 0.25 1 .........................
Manganese compounds (as Mn)............... 7439-96-5 ............ (C)5 .........................
Manganese fume (as Mn).................... 7439-96-5 ............ (C)5 .........................
Marble.................................... 1317-65-3
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Mercury (aryl and inorganic) (as Hg)...... 7439-97-6 (\2\)
Mercury (organo) alkyl compounds (as Hg).. 7439-97-6 (\2\)
Mercury (vapor) (as Hg)................... 7439-97-6 (\2\)
Mesityl oxide............................. 141-79-7 25 100 .........................
Methanethiol; see Methyl mercaptan.
Methoxychlor.............................. 72-43-5
Total dust............................ ............ 15 .........................
2-Methoxyethanol (Methyl cellosolve)...... 109-86-4 25 80 X
2-Methoxyethyl acetate (Methyl cellosolve 110-49-6 25 120 X
acetate).
Methyl acetate............................ 79-20-9 200 610 .........................
[[Page 14]]
Methyl acetylene (Propyne)................ 74-99-7 1000 1650 .........................
Methyl acetylene-propadiene mixture (MAPP) 1000 1800 .........................
Methyl acrylate........................... 96-33-3 10 35 X
Methylal (Dimethoxy-methane).............. 109-87-5 1000 3100 .........................
Methyl alcohol............................ 67-56-1 200 260 .........................
Methylamine............................... 74-89-5 10 12 .........................
Methyl amyl alcohol; see Methyl isobutyl
carbinol.
Methyl n-amyl ketone...................... 110-43-0 100 465 .........................
Methyl bromide............................ 74-83-9 (C)20 (C)80 X
Methyl butyl ketone; see 2-Hexanone.
Methyl cellosolve; see 2-Methoxyethanol.
Methyl cellosolve acetate; see 2-
Methoxyethyl acetate.
Methyl chloride........................... 74-87-3 (\2\)
Methyl chloroform (1,1,1-Trichloroethane). 71-55-6 350 1900 .........................
Methylcyclohexane......................... 108-87-2 500 2000 .........................
Methylcyclohexanol........................ 25639-42-3 100 470 .........................
o-Methylcyclohexanone..................... 583-60-8 100 460 X
Methylene chloride........................ 75-09-2 (\2\)
Methyl ethyl ketone (MEK); see 2-Butanone.
Methyl formate............................ 107-31-3 100 250 .........................
Methyl hydrazine (Monomethyl hydrazine)... 60-34-4 (C)0.2 (C)0.35 X
Methyl iodide............................. 74-88-4 5 28 X
Methyl isoamyl ketone..................... 110-12-3 100 475 .........................
Methyl isobutyl carbinol.................. 108-11-2 25 100 X
Methyl isobutyl ketone; see Hexone.
Methyl isocyanate......................... 624-83-9 0.02 0.05 X
Methyl mercaptan.......................... 74-93-1 (C)10 (C)20 .........................
Methyl methacrylate....................... 80-62-6 100 410 .........................
Methyl propyl ketone; see 2-Pentanone.
alpha-Methyl styrene...................... 98-83-9 (C)100 (C)480 .........................
Methylene bisphenyl isocyanate (MDI)...... 101-68-8 (C)0.02 (C)0.2 .........................
Mica; see Silicates.
Molybdenum (as Mo)........................ 7439-98-7
Soluble compounds..................... ............ 5 .........................
Insoluble compounds.
Total dust........................ ............ 15 .........................
Monomethyl aniline........................ 100-61-8 2 9 X
Monomethyl hydrazine; see Methyl
hydrazine.
Morpholine................................ 110-91-8 20 70 X
Naphtha (Coal tar)........................ 8030-30-6 100 400 .........................
Naphthalene............................... 91-20-3 10 50 .........................
alpha-Naphthylamine; see 1910.1004........ 134-32-7
beta-Naphthylamine; see 1910.1009......... 91-59-8
Nickel carbonyl (as Ni)................... 13463-39-3 0.001 0.007 .........................
Nickel, metal and insoluble compounds (as 7440-02-0 ............ 1 .........................
Ni).
Nickel, soluble compounds (as Ni)......... 7440-02-0 ............ 1 .........................
Nicotine.................................. 54-11-5 ............ 0.5 X
Nitric acid............................... 7697-37-2 2 5 .........................
Nitric oxide.............................. 10102-43-9 25 30 .........................
p-Nitroaniline............................ 100-01-6 1 6 X
Nitrobenzene.............................. 98-95-3 1 5 X
p-Nitrochlorobenzene...................... 100-00-5 ............ 1 X
4-Nitrodiphenyl; see 1910.1003............ 92-93-3
Nitroethane............................... 79-24-3 100 310 .........................
Nitrogen dioxide.......................... 10102-44-0 (C)5 (C)9 .........................
Nitrogen trifluoride...................... 7783-54-2 10 29 .........................
Nitroglycerin............................. 55-63-0 (C)0.2 (C)2 X
Nitromethane.............................. 75-52-5 100 250 .........................
1-Nitropropane............................ 108-03-2 25 90 .........................
2-Nitropropane............................ 79-46-9 25 90 .........................
N-Nitrosodimethylamine; see 1910.1016.
Nitrotoluene (all isomers)................ 5 30 X
o-isomer.............................. 88-72-2
m-isomer.............................. 99-08-1
p-isomer.............................. 99-99-0
Nitrotrichloromethane; see Chloropicrin.
Octachloronaphthalene..................... 2234-13-1 ............ 0.1 X
Octane.................................... 111-65-9 500 2350 .........................
Oil mist, mineral......................... 8012-95-1 ............ 5 .........................
Osmium tetroxide (as Os).................. 20816-12-0 ............ 0.002 .........................
Oxalic acid............................... 144-62-7 ............ 1 .........................
Oxygen difluoride......................... 7783-41-7 0.05 0.1 .........................
[[Page 15]]
Ozone..................................... 10028-15-6 0.1 0.2 .........................
Paraquat, respirable dust................. 4685-14-7; ............ 0.5 X
1910-42-5;
2074-50-2
Parathion................................. 56-38-2 ............ 0.1 X
Particulates not otherwise regulated
(PNOR) f.
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
PCB; see Chlorodiphenyl (42% and 54%
chlorine).
Pentaborane............................... 19624-22-7 0.005 0.01 .........................
Pentachloronaphthalene.................... 1321-64-8 ............ 0.5 X
Pentachlorophenol......................... 87-86-5 ............ 0.5 X
Pentaerythritol........................... 115-77-5
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Pentane................................... 109-66-0 1000 2950 .........................
2-Pentanone (Methyl propyl ketone)........ 107-87-9 200 700 .........................
Perchloroethylene (Tetrachloroethylene)... 127-18-4 (\2\)
Perchloromethyl mercaptan................. 594-42-3 0.1 0.8 .........................
Perchloryl fluoride....................... 7616-94-6 3 13.5 .........................
Petroleum distillates (Naphtha) (Rubber 500 2000 .........................
Solvent).
Phenol.................................... 108-95-2 5 19 X
p-Phenylene diamine....................... 106-50-3 ............ 0.1 X
Phenyl ether, vapor....................... 101-84-8 1 7 .........................
Phenyl ether-biphenyl mixture, vapor...... 1 7 .........................
Phenylethylene; see Styrene.
Phenyl glycidyl ether (PGE)............... 122-60-1 10 60 .........................
Phenylhydrazine........................... 100-63-0 5 22 X
Phosdrin (Mevinphos)...................... 7786-34-7 ............ 0.1 X
Phosgene (Carbonyl chloride).............. 75-44-5 0.1 0.4 .........................
Phosphine................................. 7803-51-2 0.3 0.4 .........................
Phosphoric acid........................... 7664-38-2 ............ 1 .........................
Phosphorus (yellow)....................... 7723-14-0 ............ 0.1 .........................
Phosphorus pentachloride.................. 10026-13-8 ............ 1 .........................
Phosphorus pentasulfide................... 1314-80-3 ............ 1 .........................
Phosphorus trichloride.................... 7719-12-2 0.5 3 .........................
Phthalic anhydride........................ 85-44-9 2 12 .........................
Picloram.................................. 1918-02-1
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Picric acid............................... 88-89-1 ............ 0.1 X
Pindone (2-Pivalyl-1,3-indandione)........ 83-26-1 ............ 0.1 .........................
Plaster of Paris.......................... 26499-65-0
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Platinum (as Pt).......................... 7440-06-4
Metal................................. ............ ........... .........................
Soluble salts......................... ............ 0.002 .........................
Portland cement........................... 65997-15-1
Total dust............................ 15 .........................
Respirable fraction................... ............ 5 .........................
Propane................................... 74-98-6 1000 1800 .........................
beta-Propriolactone; see 1910.1013........ 57-57-8
n-Propyl acetate.......................... 109-60-4 200 840 .........................
n-Propyl alcohol.......................... 71-23-8 200 500 .........................
n-Propyl nitrate.......................... 627-13-4 25 110 .........................
Propylene dichloride...................... 78-87-5 75 350 .........................
Propylene imine........................... 75-55-8 2 5 X
Propylene oxide........................... 75-56-9 100 240 .........................
Propyne; see Methyl acetylene.
Pyrethrum................................. 8003-34-7 ............ 5 .........................
Pyridine.................................. 110-86-1 5 15 .........................
Quinone................................... 106-51-4 0.1 0.4 .........................
RDX; see Cyclonite.
Rhodium (as Rh), metal fume and insoluble 7440-16-6 ............ 0.1 .........................
compounds.
Rhodium (as Rh), soluble compounds........ 7440-16-6 ............ 0.001 .........................
Ronnel.................................... 299-84-3 ............ 15 .........................
Rotenone.................................. 83-79-4 ............ 5 .........................
Rouge.....................................
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Selenium compounds (as Se)................ 7782-49-2 ............ 0.2 .........................
[[Page 16]]
Selenium hexafluoride (as Se)............. 7783-79-1 0.05 0.4 .........................
Silica, amorphous, precipitated and gel... 112926-00-8 (\3\) .........................
Silica, amorphous, diatomaceous earth, 61790-53-2 (\3\)
containing less than 1% crystalline
silica.
Silica, crystalline cristobalite, 14464-46-1 (\3\)
respirable dust.
Silica, crystalline quartz, respirable 14808-60-7 (\3\)
dust.
Silica, crystalline tripoli (as quartz), 1317-95-9 (\3\)
respirable dust.
Silica, crystalline tridymite, respirable 15468-32-3 (\3\)
dust.
Silica, fused, respirable dust............ 60676-86-0 (\3\)
Silicates (less than 1% crystalline
silica).
Mica (respirable dust)................ 12001-26-2 (\3\)
Soapstone, total dust................. .............. (\3\)
Soapstone, respirable dust............ .............. (\3\)
Talc (containing asbestos); use .............. (\3\)
asbestos limit; see 29 CFR 1910.1001.
Talc (containing no asbestos), 14807-96-6 (\3\)
respirable dust.
Tremolite, asbestiform; see 1910.1001.
Silicon................................... 7440-21-3
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Silicon carbide........................... 409-21-2
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Silver, metal and soluble compounds (as 7440-22-4 ............ 0.01 .........................
Ag).
Soapstone; see Silicates.
Sodium fluoroacetate...................... 62-74-8 ............ 0.05 X
Sodium hydroxide.......................... 1310-73-2 ............ 2 .........................
Starch.................................... 9005-25-8
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Stibine................................... 7803-52-3 0.1 0.5 .........................
Stoddard solvent.......................... 8052-41-3 500 2900 .........................
Strychnine................................ 57-24-9 ............ 0.15 .........................
Styrene................................... 100-42-5 (\2\)
Sucrose................................... 57-50-1
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Sulfur dioxide............................ 7446-09-5 5 13 .........................
Sulfur hexafluoride....................... 2551-62-4 1000 6000 .........................
Sulfuric acid............................. 7664-93-9 ............ 1 .........................
Sulfur monochloride....................... 10025-67-9 1 6 .........................
Sulfur pentafluoride...................... 5714-22-7 0.025 0.25 .........................
Sulfuryl fluoride......................... 2699-79-8 5 20 .........................
Systox; see Demeton.
2,4,5-T (2,4,5-trichlorophenoxyacetic 93-76-5 ............ 10 .........................
acid).
Talc; see Silicates.
Tantalum, metal and oxide dust............ 7440-25-7 ............ 5 .........................
TEDP (Sulfotep)........................... 3689-24-5 ............ 0.2 X
Tellurium and compounds (as Te)........... 13494-80-9 ............ 0.1 .........................
Tellurium hexafluoride (as Te)............ 7783-80-4 0.02 0.2 .........................
Temephos.................................. 3383-96-8
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
TEPP (Tetraethyl pyrophosphate)........... 107-49-3 ............ 0.05 X
Terphenyls................................ 26140-60-3 (C)1 (C)9 .........................
1,1,1,2-Tetrachloro-2,2-difluoroethane.... 76-11-9 500 4170 .........................
1,1,2,2-Tetrachloro-1,2-difluoroethane.... 76-12-0 500 4170 .........................
1,1,2,2-Tetrachloroethane................. 79-34-5 5 35 X
Tetrachloroethylene; see
Perchloroethylene.
Tetrachloromethane; see Carbon
tetrachloride.
Tetrachloronaphthalene.................... 1335-88-2 ............ 2 X
Tetraethyl lead (as Pb)................... 78-00-2 ............ 0.075 X
Tetrahydrofuran........................... 109-99-9 200 590 .........................
Tetramethyl lead (as Pb).................. 75-74-1 ............ 0.075 X
Tetramethyl succinonitrile................ 3333-52-6 0.5 3 X
Tetranitromethane......................... 509-14-8 1 8 .........................
Tetryl (2,4,6- 479-45-8 ............ 1.5 X
Trinitrophenylmethylnitramine).
Thallium, soluble compounds (as Tl)....... 7440-28-0 ............ 0.1 X
4,4'-Thiobis (6-tert, Butyl-m-cresol)..... 96-69-5
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Thiram.................................... 137-26-8 ............ 5 .........................
[[Page 17]]
Tin, inorganic compounds (except oxides) 7440-31-5 ............ 2 .........................
(as Sn).
Tin, organic compounds (as Sn)............ 7440-31-5 ............ 0.1 .........................
Titanium dioxide.......................... 13463-67-7
Total dust............................ ............ 15 .........................
Toluene................................... 108-88-3 (\2\)
Toluene-2,4-diisocyanate (TDI)............ 584-84-9 (C)0.02 (C)0.14 .........................
o-Toluidine............................... 95-53-4 5 22 X
Toxaphene; see Chlorinated camphene.
Tremolite; see Silicates.
Tributyl phosphate........................ 126-73-8 ............ 5 .........................
1,1,1-Trichloroethane; see Methyl
chloroform.
1,1,2-Trichloroethane..................... 79-00-5 10 45 X
Trichloroethylene......................... 79-01-6 (\2\)
Trichloromethane; see Chloroform.
Trichloronaphthalene...................... 1321-65-9 ............ 5 X
1,2,3-Trichloropropane.................... 96-18-4 50 300 .........................
1,1,2-Trichloro-1,2,2-trifluoroethane..... 76-13-1 1000 7600 .........................
Triethylamine............................. 121-44-8 25 100 .........................
Trifluorobromomethane..................... 75-63-8 1000 6100 .........................
2,4,6-Trinitrophenol; see Picric acid.
2,4,6-Trinitrophenylmethylnitramine; see
Tetryl.
2,4,6-Trinitrotoluene (TNT)............... 118-96-7 ............ 1.5 X
Triorthocresyl phosphate.................. 78-30-8 ............ 0.1 .........................
Triphenyl phosphate....................... 115-86-6 ............ 3 .........................
Turpentine................................ 8006-64-2 100 560 .........................
Uranium (as U)............................ 7440-61-1
Soluble compounds..................... ............ 0.05 .........................
Insoluble compounds................... ............ 0.25 .........................
Vanadium.................................. 1314-62-1
Respirable dust (as V2 O5)............ ............ (C)0.5 .........................
Fume (as V2 O5)....................... ............ (C)0.1 .........................
Vegetable oil mist........................
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Vinyl benzene; see Styrene.
Vinyl chloride; see 1910.1017............. 75-01-4
Vinyl cyanide; see Acrylonitrile.
Vinyl toluene............................. 25013-15-4 100 480 .........................
Warfarin.................................. 81-81-2 ............ 0.1 .........................
Xylenes (o-, m-, p-isomers)............... 1330-20-7 100 435 .........................
Xylidine.................................. 1300-73-8 5 25 X
Yttrium................................... 7440-65-5 ............ 1 .........................
Zinc chloride fume........................ 7646-85-7 ............ 1 .........................
Zinc oxide fume........................... 1314-13-2 ............ 5 .........................
Zinc oxide................................ 1314-13-2
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Zinc stearate............................. 557-05-1
Total dust............................ ............ 15 .........................
Respirable fraction................... ............ 5 .........................
Zirconium compounds (as Zr)............... 7440-67-7 ............ 5 .........................
----------------------------------------------------------------------------------------------------------------
\1\ The PELs are 8-hour TWAs unless otherwise noted; a (C) designation denotes a ceiling limit. They are to be
determined from breathing-zone air samples.
(a) Parts of vapor or gas per million parts of contaminated air by volume at 25 C and 760 torr.
(b) Milligrams of substance per cubic meter of air. When entry is in this column only, the value is exact; when
listed with a ppm entry, it is approximate.
(c) The CAS number is for information only. Enforcement is based on the substance name. For an entry covering
more than one metal compound, measured as the metal, the CAS number for the metal is given--not CAS numbers
for the individual compounds.
(d) The final benzene standard in 1910.1028 applies to all occupational exposures to benzene except in some
circumstances the distribution and sale of fuels, sealed containers and pipelines, coke production, oil and
gas drilling and production, natural gas processing, and the percentage exclusion for liquid mixtures; for the
excepted subsegments, the benzene limits in Table Z-2 apply. See 1910.1028 for specific circumstances.
(e) This 8-hour TWA applies to respirable dust as measured by a vertical elutriator cotton dust sampler or
equivalent instrument. The time-weighted average applies to the cottom waste processing operations of waste
recycling (sorting, blending, cleaning and willowing) and garnetting. See also 1910.1043 for cotton dust
limits applicable to other sectors.
(f) All inert or nuisance dusts, whether mineral, inorganic, or organic, not listed specifically by substance
name are covered by the Particulates Not Otherwise Regulated (PNOR) limit which is the same as the inert or
nuisance dust limit of Table Z-3.
\2\ See Table Z-2.
\3\ See Table Z-3.
\4\ Varies with compound.
[[Page 18]]
Table Z-2
----------------------------------------------------------------------------------------------------------------
Acceptable maximum peak above the
acceptable ceiling concentration for an
Substance 8-hour time Acceptable ceiling 8-hr shift
weighted average concentration ----------------------------------------
Concentration Maximum duration
----------------------------------------------------------------------------------------------------------------
Benzenea (Z37.40-1969)......... 10 ppm............ 25 ppm............ 50 ppm............ 10 minutes.
Beryllium and beryllium 2 g/m3... 5 g/m3... 25 g/m3.. 30 minutes.
compounds (Z37.29-1970).
Cadmium fumeb (Z37.5-1970)..... 0.1 mg/m3......... 0.3 mg/m3......... .................. ...................
Cadmium dustb (Z37.5-1970)..... 0.2 mg/m3......... 0.6 mg/m3.........
Carbon disulfide (Z37.3-1968).. 20 ppm............ 30 ppm............ 100 ppm........... 30 minutes.
Carbon tetrachloride (Z37.17- 10 ppm............ 25 ppm............ 200 ppm........... 5 min. in any 4
1967). hrs.
Chromic acid and chromates .................. 1 mg/10m3.........
(Z37.7-1971).
Ethylene dibromide (Z37.31- 20 ppm............ 30 ppm............ 50 ppm............ 5 minutes.
1970).
Ethylene dichloride (Z37.21- 50 ppm............ 100 ppm........... 200 ppm........... 5 min. in any 3
1969). hrs.
Fluoride as dust (Z37.28-1969). 2.5 mg/m3......... .................. .................. ...................
Formaldehyde; see 1910.1048.... .................. .................. .................. ...................
Hydrogen fluoride (Z37.28-1969) 3 ppm............. .................. .................. ...................
Hydrogen sulfide (Z37.2-1966).. .................. 20 ppm............ 50 ppm............ 10 mins. once, only
if no other meas.
exp. occurs.
Mercury (Z37.8-1971)........... .................. 1 mg/10m3......... .................. ...................
Methyl chloride (Z37.18-1969).. 100 ppm........... 200 ppm........... 300 ppm........... 5 mins. in any 3
hrs.
Methylene Chloride: See Sec.
1919.52..
Organo (alkyl) mercury (Z37.30- 0.01 mg/m3........ 0.04 mg/m3........ .................. ...................
1969).
Styrene (Z37.15-1969).......... 100 ppm........... 200 ppm........... 600 ppm........... 5 mins. in any 3
hrs.
Tetrachloroethylene (Z37.22- 100 ppm........... 200 ppm........... 300 ppm........... 5 mins. in any 3
1967). hrs.
Toluene (Z37.12-1967).......... 200 ppm........... 300 ppm........... 500 ppm........... 10 minutes.
Trichloroethylene (Z37.19-1967) 100 ppm........... 200 ppm........... 300 ppm........... 5 mins. in any 2
hrs.
----------------------------------------------------------------------------------------------------------------
a This standard applies to the industry segments exempt from the 1 ppm 8-hour TWA and 5 ppm STEL of the benzene
standard at 1910.1028.
b This standard applies to any operations or sectors for which the Cadmium standard, 1910.1027, is stayed or
otherwise not in effect.
Table Z-3--Mineral Dusts
------------------------------------------------------------------------
Substance mppcf a mg/m\3\
------------------------------------------------------------------------
Silica:
Crystalline
250 b 10 mg/m\3\
e
Quartz (Respirable)....................... ---------- ----------
%SiO2+5 % SiO2 + 2
30 mg/m\3\
Quartz (Total Dust)....................... ........... ----------
% SiO2 + 2
Cristobalite: Use \1/2\ the value calculated
from the count or mass formulae for quartz
Tridymite: Use \1/2\ the value calculated
from the formulae for quartz
80 mg/m\3\
Amorphous, including natural diatomaceous 20 ----------
earth........................................ %SiO2
Silicates (less than 1% crystalline silica):
Mica........................................ 20
Soapstone................................... 20
Talc (not containing asbestos).............. 20 c
Talc (containing asbestos) Use asbestos
limit......................................
Tremolite, asbestiform (see 29 CFR
1910.1001).................................
Portland cement............................. 50
Graphite (Natural)............................ 15
Coal Dust:
Respirable fraction less than 5% SiO2....... ........... 2.4 mg/
m\3\ e
[[Page 19]]
10 mg/m3 e
Respirable fraction greater than 5% SiO2.... ........... ----------
%SiO2+2
Inert or Nuisance Dust: d
Respirable fraction......................... 15 5 mg/m\3\
Total dust.................................. 50 15 mg/m\3\
------------------------------------------------------------------------
Note--Conversion factors - mppcf X 35.3 = million particles per cubic
meter = particles per c.c.
a Millions of particles per cubic foot of air, based on impinger samples
counted by light-field techniques.
b The percentage of crystalline silica in the formula is the amount
determined from airborne samples, except in those instances in which
other methods have been shown to be applicable.
c Containing less than 1% quartz; if 1% quartz or more, use quartz
limit.
d All inert or nuisance dusts, whether mineral, inorganic, or organic,
not listed specifically by substance name are covered by this limit,
which is the same as the Particulates Not Otherwise Regulated (PNOR)
limit in Table Z-1.
e Both concentration and percent quartz for the application of this
limit are to be determined from the fraction passing a size-selector
with the following characteristics:
------------------------------------------------------------------------
Percent passing
Aerodynamic diameter (unit density sphere) selector
------------------------------------------------------------------------
2.................................................... 90
2.5.................................................. 75
3.5.................................................. 50
5.0.................................................. 25
10................................................... 0
------------------------------------------------------------------------
The measurements under this note refer to the use of an AEC (now NRC)
instrument. The respirable fraction of coal dust is determined with an
MRE; the figure corresponding to that of 2.4 mg/m3 in the table for
coal dust is 4.5 mg/m3K.
[58 FR 35340, June 30. 1993; 58 FR 40191, July 27, 1993, as amended at
61 FR 56831, Nov. 4, 1996; 62 FR 1600, Jan. 10, 1997; 62 FR 42018, Aug.
4, 1997]
Sec. 1910.1001 Asbestos.
(a) Scope and application. (1) This section applies to all
occupational exposures to asbestos in all industries covered by the
Occupational Safety and Health Act, except as provided in paragraph
(a)(2) and (3) of this section.
(2) This section does not apply to construction work as defined in
29 CFR 1910.12(b). (Exposure to asbestos in construction work is covered
by 29 CFR 1926.1101).
(3) This section does not apply to ship repairing, shipbuilding and
shipbreaking employments and related employments as defined in 29 CFR
1915.4. (Exposure to asbestos in these employments is covered by 29 CFR
1915.1001).
(b) Definitions.
Asbestos includes chrysotile, amosite, crocidolite, tremolite
asbestos, anthophyllite asbestos, actinolite asbestos, and any of these
minerals that have been chemically treated and/or altered.
Asbestos-containing material (ACM) means any material containing
more than 1% asbestos.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person authorized by the employer and
required by work duties to be present in regulated areas.
Building/facility owner is the legal entity, including a lessee,
which exercises control over management and record keeping functions
relating to a building and/or facility in which activities covered by
this standard take place.
Certified industrial hygienist (CIH) means one certified in the
practice of industrial hygiene by the American Board of Industrial
Hygiene.
Director means the Director of the National Institute for
Occupational Safety and Health, U.S. Department of Health and Human
Services, or designee.
Employee exposure means that exposure to airborne asbestos that
would occur if the employee were not using respiratory protective
equipment.
Fiber means a particulate form of asbestos 5 micrometers or
longer,with a
[[Page 20]]
length-to-diameter ratio of at least 3 to 1.
High-efficiency particulate air (HEPA) filter means a filter capable
of trapping and retaining at least 99.97 percent of 0.3 micrometer
diameter mono-disperse particles.
Homogeneous area means an area of surfacing material or thermal
system insulation that is uniform in color and texture.
Industrial hygienist means a professional qualified by education,
training, and experience to anticipate, recognize, evaluate and develop
controls for occupational health hazards.
PACM means ``presumed asbestos containing material.''
Presumed asbestos containing material means thermal system
insulation and surfacing material found in buildings constructed no
later than 1980. The designation of a material as ``PACM'' may be
rebutted pursuant to paragraph (j)(8) of this section.
Regulated area means an area established by the employer to
demarcate areas where airborne concentrations of asbestos exceed, or
there is a reasonable possibility they may exceed, the permissible
exposure limits.
Surfacing ACM means surfacing material which contains more than 1%
asbestos.
Surfacing material means material that is sprayed, troweled-on or
otherwise applied to surfaces (such as acoustical plaster on ceilings
and fireproofing materials on structural members, or other materials on
surfaces for acoustical, fireproofing, and other purposes).
Thermal System Insulation (TSI) means ACM applied to pipes,
fittings, boilers, breeching, tanks, ducts or other structural
components to prevent heat loss or gain.
Thermal System Insulation ACM means thermal system insulation which
contains more than 1% asbestos.
(c) Permissible exposure limit (PELS)--(1) Time-weighted average
limit (TWA). The employer shall ensure that no employee is exposed to an
airborne concentration of asbestos in excess of 0.1 fiber per cubic
centimeter of air as an eight (8)-hour time-weighted average (TWA) as
determined by the method prescribed in Appendix A to this section, or by
an equivalent method.
(2) Excursion limit. The employer shall ensure that no employee is
exposed to an airborne concentration of asbestos in excess of 1.0 fiber
per cubic centimeter of air (1 f/cc) as averaged over a sampling period
of thirty (30) minutes as determined by the method prescribed in
Appendix A to this section, or by an equivalent method.
(d) Exposure monitoring--(1) General. (i) Determinations of employee
exposure shall be made from breathing zone air samples that are
representative of the 8-hour TWA and 30-minute short-term exposures of
each employee.
(ii) Representative 8-hour TWA employee exposures shall be
determined on the basis of one or more samples representing full-shift
exposures for each shift for each employee in each job classification in
each work area. Representative 30-minute short-term employee exposures
shall be determined on the basis of one or more samples representing 30
minute exposures associated with operations that are most likely to
produce exposures above the excursion limit for each shift for each job
classification in each work area.
(2) Initial monitoring. (i) Each employer who has a workplace or
work operation covered by this standard, except as provided for in
paragraphs (d)(2)(ii) and (d)(2)(iii) of this section, shall perform
initial monitoring of employees who are, or may reasonably be expected
to be exposed to airborne concentrations at or above the TWA permissible
exposure limit and/or excursion limit.
(ii) Where the employer has monitored after March 31, 1992, for the
TWA permissible exposure limit and/or the excursion limit, and the
monitoring satisfies all other requirements of this section, the
employer may rely on such earlier monitoring results to satisfy the
requirements of paragraph (d)(2)(i) of this section.
(iii) Where the employer has relied upon objective data that
demonstrate that asbestos is not capable of being released in airborne
concentrations at or above the TWA permissible exposure limit and/or
excursion limit under the expected conditions of processing, use,
[[Page 21]]
or handling, then no initial monitoring is required.
(3) Monitoring frequency (periodic monitoring) and patterns. After
the initial determinations required by paragraph (d)(2)(i) of this
section, samples shall be of such frequency and pattern as to represent
with reasonable accuracy the levels of exposure of the employees. In no
case shall sampling be at intervals greater than six months for
employees whose exposures may reasonably be foreseen to exceed the TWA
permissible exposure limit and/or excursion limit.
(4) Changes in monitoring frequency. If either the initial or the
periodic monitoring required by paragraphs (d)(2) and (d)(3) of this
section statistically indicates that employee exposures are below the
TWA permissible exposure limit and/or excursion limit, the employer may
discontinue the monitoring for those employees whose exposures are
represented by such monitoring.
(5) Additional monitoring. Notwithstanding the provisions of
paragraphs (d)(2)(ii) and (d)(4) of this section, the employer shall
institute the exposure monitoring required under paragraphs (d)(2)(i)
and (d)(3) of this section whenever there has been a change in the
production, process, control equipment, personnel or work practices that
may result in new or additional exposures above the TWA permissible
exposure limit and/or excursion limit or when the employer has any
reason to suspect that a change may result in new or additional
exposures above the PEL and/or excursion limit.
(6) Method of monitoring. (i) All samples taken to satisfy the
monitoring requirements of paragraph (d) of this section shall be
personal samples collected following the procedures specified in
Appendix A.
(ii) All samples taken to satisfy the monitoring requirements of
paragraph (d) of this section shall be evaluated using the OSHA
Reference Method (ORM) specified in Appendix A of this section, or an
equivalent counting method.
(iii) If an equivalent method to the ORM is used, the employer shall
ensure that the method meets the following criteria:
(A) Replicate exposure data used to establish equivalency are
collected in side-by-side field and laboratory comparisons; and
(B) The comparison indicates that 90% of the samples collected in
the range 0.5 to 2.0 times the permissible limit have an accuracy range
of plus or minus 25 percent of the ORM results at a 95% confidence level
as demonstrated by a statistically valid protocol; and
(C) The equivalent method is documented and the results of the
comparison testing are maintained.
(iv) To satisfy the monitoring requirements of paragraph (d) of this
section, employers must use the results of monitoring analysis performed
by laboratories which have instituted quality assurance programs that
include the elements as prescribed in Appendix A of this section.
(7) Employee notification of monitoring results. (i) The employer
shall, within 15 working days after the receipt of the results of any
monitoring performed under the standard, notify the affected employees
of these results in writing either individually or by posting of results
in an appropriate location that is accessible to affected employees.
(ii) The written notification required by paragraph (d)(7)(i) of
this section shall contain the corrective action being taken by the
employer to reduce employee exposure to or below the TWA and/or
excursion limit, wherever monitoring results indicated that the TWA and/
or excursion limit had been exceeded.
(e) Regulated Areas--(1) Establishment. The employer shall establish
regulated areas wherever airborne concentrations of asbestos and/or PACM
are in excess of the TWA and/or excursion limit prescribed in paragraph
(c) of this section.
(2) Demarcation. Regulated areas shall be demarcated from the rest
of the workplace in any manner that minimizes the number of persons who
will be exposed to asbestos.
(3) Access. Access to regulated areas shall be limited to authorized
persons or to persons authorized by the Act or regulations issued
pursuant thereto.
(4) Provision of respirators. Each person entering a regulated area
shall be
[[Page 22]]
supplied with and required to use a respirator, selected in accordance
with paragraph (g)(2) of this section.
(5) Prohibited activities. The employer shall ensure that employees
do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in the
regulated areas.
(f) Methods of compliance--(1) Engineering controls and work
practices. (i) The employer shall institute engineering controls and
work practices to reduce and maintain employee exposure to or below the
TWA and/or excursion limit prescribed in paragraph (c) of this section,
except to the extent that such controls are not feasible.
(ii) Wherever the feasible engineering controls and work practices
that can be instituted are not sufficient to reduce employee exposure to
or below the TWA and/or excursion limit prescribed in paragraph (c) of
this section, the employer shall use them to reduce employee exposure to
the lowest levels achievable by these controls and shall supplement them
by the use of respiratory protection that complies with the requirements
of paragraph (g) of this section.
(iii) For the following operations, wherever feasible engineering
controls and work practices that can be instituted are not sufficient to
reduce the employee exposure to or below the TWA and/or excursion limit
prescribed in paragraph (c) of this section, the employer shall use them
to reduce employee exposure to or below 0.5 fiber per cubic centimeter
of air (as an eight-hour time-weighted average) or 2.5 fibers/cc for 30
minutes (short-term exposure) and shall supplement them by the use of
any combination of respiratory protection that complies with the
requirements of paragraph (g) of this section, work practices and
feasible engineering controls that will reduce employee exposure to or
below the TWA and to or below the excursion limit permissible prescribed
in paragraph (c) of this section: Coupling cutoff in primary asbestos
cement pipe manufacturing; sanding in primary and secondary asbestos
cement sheet manufacturing; grinding in primary and secondary friction
product manufacturing; carding and spinning in dry textile processes;
and grinding and sanding in primary plastics manufacturing.
(iv) Local exhaust ventilation. Local exhaust ventilation and dust
collection systems shall be designed, constructed, installed, and
maintained in accordance with good practices such as those found in the
American National Standard Fundamentals Governing the Design and
Operation of Local Exhaust Systems, ANSI Z9.2-1979.
(v) Particular tools. All hand-operated and power-operated tools
which would produce or release fibers of asbestos, such as, but not
limited to, saws, scorers, abrasive wheels, and drills, shall be
provided with local exhaust ventilation systems which comply with
paragraph (f)(1)(iv) of this section.
(vi) Wet methods. Insofar as practicable, asbestos shall be handled,
mixed, applied, removed, cut, scored, or otherwise worked in a wet state
sufficient to prevent the emission of airborne fibers so as to expose
employees to levels in excess of the TWA and/or excursion limit,
prescribed in paragraph (c) of this section, unless the usefulness of
the product would be diminished thereby.
(vii) [Reserved]
(viii) Particular products and operations. No asbestos cement,
mortar, coating, grout, plaster, or similar material containing
asbestos, shall be removed from bags, cartons, or other containers in
which they are shipped, without being either wetted, or enclosed, or
ventilated so as to prevent effectively the release of airborne fibers.
(ix) Compressed air. Compressed air shall not be used to remove
asbestos or materials containing asbestos unless the compressed air is
used in conjunction with a ventilation system which effectively captures
the dust cloud created by the compressed air.
(x) Flooring. Sanding of asbestos-containing flooring material is
prohibited.
(2) Compliance program. (i) Where the TWA and/or excursion limit is
exceeded, the employer shall establish and implement a written program
to reduce employee exposure to or below the TWA and to or below the
excursion limit by means of engineering and work practice controls as
required by paragraph (f)(1) of this section, and by the use of
respiratory protection where
[[Page 23]]
required or permitted under this section.
(ii) Such programs shall be reviewed and updated as necessary to
reflect significant changes in the status of the employer's compliance
program.
(iii) Written programs shall be submitted upon request for
examination and copying to the Assistant Secretary, the Director,
affected employees and designated employee representatives.
(iv) The employer shall not use employee rotation as a means of
compliance with the TWA and/or excursion limit.
(3) Specific compliance methods for brake and clutch repair:
(i) Engineering controls and work practices for brake and clutch
repair and service. During automotive brake and clutch inspection,
disassembly, repair and assembly operations, the employer shall
institute engineering controls and work practices to reduce employee
exposure to materials containing asbestos using a negative pressure
enclosure/HEPA vacuum system method or low pressure/wet cleaning method,
which meets the detailed requirements set out in Appendix F to this
section. The employer may also comply using an equivalent method which
follows written procedures which the employer demonstrates can achieve
results equivalent to Method A in Appendix F to this section. For
facilities in which no more than 5 pair of brakes or 5 clutches are
inspected, disassembled, repaired, or assembled per week, the method set
forth in paragraph [D] of Appendix F to this section may be used.
(ii) The employer may also comply by using an equivalent method
which follows written procedures, which the employer demonstrates can
achieve equivalent exposure reductions as do the two ``preferred
methods.'' Such demonstration must include monitoring data conducted
under workplace conditions closely resembling the process, type of
asbestos containing materials, control method, work practices and
environmental conditions which the equivalent method will be used, or
objective data, which document that under all reasonably foreseeable
conditions of brake and clutch repair applications, the method results
in exposures which are equivalent to the methods set out in Appendix F
to this section.
(g) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide
respirators that comply with the requirements of this paragraph.
Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls.
(ii) Work operations, such as maintenance and repair activities, for
which engineering and work-practice controls are not feasible.
(iii) Work operations for which feasible engineering and work-
practice controls are not yet sufficient to reduce employee exposure to
or below the TWA and/or excursion limit.
(iv) Emergencies.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance with 29 CFR 1910.134 (b)
through (d) (except (d)(1)(iii)), and (f) through (m).
(ii) The employer must provide a tight-fitting, powered, air-
purifying respirator instead of any negative-pressure respirator
specified in Table 1 of this section when an employee chooses to use
this type of respirator and the respirator provides adequate protection
to the employee.
(iii) No employee must be assigned to tasks requiring the use of
respirators if, based on their most recent medical examination, the
examining physician determines that the employee will be unable to
function normally using a respirator, or that the safety or health of
the employee or other employees will be impaired by the use of a
respirator. Such employees must be assigned to another job or given the
opportunity to transfer to a different position, the duties of which
they can perform. If such a transfer position is available, the position
must be with the same employer, in the same geographical area, and with
the same seniority, status, and rate of pay the employee had just prior
to such transfer.
[[Page 24]]
(3) Respirator selection. The employer must select and provide the
appropriate respirator from Table 1 of this section.
Table 1--Respiratory Protection for Asbestos Fibers
------------------------------------------------------------------------
Airborne concentration of
asbestos or conditions of use Required respirator
------------------------------------------------------------------------
Not in excess of 1 f/cc (10 X Half-mask air purifying respirator other
PEL). than a disposable respirator, equipped
with high efficiency filters.
Not in excess of 5 f/cc (50 X Full facepiece air-purifying respirator
PEL). equipped with high efficiency filters.
Not in excess of 10 f/cc (100 Any powered air-purifying respirator
X PEL). equipped with high efficiency filters or
any supplied air respirator operated in
continuous flow mode.
Not in excess of 100 f/cc Full facepiece supplied air respirator
(1,000 X PEL). operated in pressure demand mode.
Greater than 100 f/cc (1,000 Full facepiece supplied air respirator
X PEL) or unknown operated in pressure demand mode,
concentration. equipped with an auxiliary positive
pressure self-contained breathing
apparatus.
------------------------------------------------------------------------
Note: a. Respirators assigned for high environmental concentrations may
be used at lower concentrations, or when required respirator use is
independent of concentration.
b. A high efficiency filter means a filter that is at least 99.97
percent efficient against mono-dispersed particles of 0.3 micrometers
in diameter or larger.
(h) Protective work clothing and equipment--(1) Provision and use.
If an employee is exposed to asbestos above the TWA and/or excursion
limit, or where the possibility of eye irritation exists, the employer
shall provide at no cost to the employee and ensure that the employee
uses appropriate protective work clothing and equipment such as, but not
limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, head coverings, and foot coverings; and
(iii) Face shields, vented goggles, or other appropriate protective
equipment which complies with 1910.133 of this Part.
(2) Removal and storage. (i) The employer shall ensure that
employees remove work clothing contaminated with asbestos only in change
rooms provided in accordance with paragraph (i)(1) of this section.
(ii) The employer shall ensure that no employee takes contaminated
work clothing out of the change room, except those employees authorized
to do so for the purpose of laundering, maintenance, or disposal.
(iii) Contaminated work clothing shall be placed and stored in
closed containers which prevent dispersion of the asbestos outside the
container.
(iv) Containers of contaminated protective devices or work clothing
which are to be taken out of change rooms or the workplace for cleaning,
maintenance or disposal, shall bear labels in accordance with paragraph
(j)(4) of this section.
(3) Cleaning and replacement. (i) The employer shall clean, launder,
repair, or replace protective clothing and equipment required by this
paragraph to maintain their effectiveness. The employer shall provide
clean protective clothing and equipment at least weekly to each affected
employee.
(ii) The employer shall prohibit the removal of asbestos from
protective clothing and equipment by blowing or shaking. (iii)
Laundering of contaminated clothing shall be done so as to prevent the
release of airborne fibers of asbestos in excess of the permissible
exposure limits prescribed in paragraph (c) of this section.
(iv) Any employer who gives contaminated clothing to another person
for laundering shall inform such person of the requirement in paragraph
(h)(3)(iii) of this section to effectively prevent the release of
airborne fibers of asbestos in excess of the permissible exposure
limits.
(v) The employer shall inform any person who launders or cleans
protective clothing or equipment contaminated with asbestos of the
potentially harmful effects of exposure to asbestos.
(vi) Contaminated clothing shall be transported in sealed
impermeable bags, or other closed, impermeable containers, and labeled
in accordance with paragraph (j) of this section.
(i) Hygiene facilities and practices--(1) Change rooms. (i) The
employer shall provide clean change rooms for employees who work in
areas where their airborne exposure to asbestos is above the TWA and/or
excursion limit.
[[Page 25]]
(ii) The employer shall ensure that change rooms are in accordance
with 1910.141(e) of this part, and are equipped with two separate
lockers or storage facilities, so separated as to prevent contamination
of the employee's street clothes from his protective work clothing and
equipment.
(2) Showers. (i) The employer shall ensure that employees who work
in areas where their airborne exposure is above the TWA and/or excursion
limit, shower at the end of the work shift.
(ii) The employer shall provide shower facilities which comply with
1910.141(d)(3) of this part.
(iii) The employer shall ensure that employees who are required to
shower pursuant to paragraph (i)(2)(i) of this section do not leave the
workplace wearing any clothing or equipment worn during the work shift.
(3) Lunchrooms. (i) The employer shall provide lunchroom facilities
for employees who work in areas where their airborne exposure is above
the TWA and/or excursion limit.
(ii) The employer shall ensure that lunchroom facilities have a
positive pressure, filtered air supply, and are readily accessible to
employees.
(iii) The employer shall ensure that employees who work in areas
where their airborne exposure is above the PEL and/or excursion limit
wash their hands and faces prior to eating, drinking or smoking.
(iv) The employer shall ensure that employees do not enter lunchroom
facilities with protective work clothing or equipment unless surface
asbestos fibers have been removed from the clothing or equipment by
vacuuming or other method that removes dust without causing the asbestos
to become airborne.
(4) Smoking in work areas. The employer shall ensure that employees
do not smoke in work areas where they are occupationally exposed to
asbestos because of activities in that work area.
(j) Communication of hazards to employees--Introduction. This
section applies to the communication of information concerning asbestos
hazards in general industry to facilitate compliance with this standard.
Asbestos exposure in general industry occurs in a wide variety of
industrial and commercial settings. Employees who manufacture asbestos-
containing products may be exposed to asbestos fibers. Employees who
repair and replace automotive brakes and clutches may be exposed to
asbestos fibers. In addition, employees engaged in housekeeping
activities in industrial facilities with asbestos product manufacturing
operations, and in public and commercial buildings with installed
asbestos containing materials may be exposed to asbestos fibers. Most of
these workers are covered by this general industry standard, with the
exception of state or local governmental employees in non-state plan
states. It should be noted that employees who perform housekeeping
activities during and after construction activities are covered by the
asbestos construction standard, 29 CFR 1926.1101, formerly 1926.58.
However, housekeeping employees, regardless of industry designation,
should know whether building components they maintain may expose them to
asbestos. The same hazard communication provisions will protect
employees who perform housekeeping operations in all three asbestos
standards; general industry, construction, and shipyard employment. As
noted in the construction standard, building owners are often the only
and/or best source of information concerning the presence of previously
installed asbestos containing building materials. Therefore they, along
with employers of potentially exposed employees, are assigned specific
information conveying and retention duties under this section.
(1) Installed Asbestos Containing Material. Employers and building
owners are required to treat installed TSI and sprayed on and troweled-
on surfacing materials as ACM in buildings constructed no later than
1980 for purposes of this standard. These materials are designated
``presumed ACM or PACM'', and are defined in paragraph (b) of this
section. Asphalt and vinyl flooring material installed no later than
1980 also must be treated as asbestos-containing. The employer or
building owner may demonstrate that PACM and flooring material do not
contain asbestos by complying with paragraph (j)(8)(iii) of this
section.
[[Page 26]]
(2) Duties of employers and building and facility owners. (i)
Building and facility owners shall determine the presence, location, and
quantity of ACM and/or PACM at the work site. Employers and building and
facility owners shall exercise due diligence in complying with these
requirements to inform employers and employees about the presence and
location of ACM and PACM.
(ii) Building and facility owners shall maintain records of all
information required to be provided pursuant to this section and/or
otherwise known to the building owner concerning the presence, location
and quantity of ACM and PACM in the building/facility. Such records
shall be kept for the duration of ownership and shall be transferred to
successive owners.
(iii) Building and facility owners shall inform employers of
employees, and employers shall inform employees who will perform
housekeeping activities in areas which contain ACM and/or PACM of the
presence and location of ACM and/or PACM in such areas which may be
contacted during such activities.
(3) Warning signs--(i) Posting. Warning signs shall be provided and
displayed at each regulated area. In addition, warning signs shall be
posted at all approaches to regulated areas so that an employee may read
the signs and take necessary protective steps before entering the area.
(ii) Sign specifications. (A) The warning signs required by
paragraph (j)(3) of this section shall bear the following information:
DANGER
ASBESTOS
CANCER AND LUNG DISEASE HAZARD
AUTHORIZED PERSONNEL ONLY
(B) In addition, where the use of respirators and protective
clothing is required in the regulated area under this section, the
warning signs shall include the following:
RESPIRATORS AND PROTECTIVE CLOTHING
ARE REQUIRED IN THIS AREA
(iii) [Reserved]
(iv) The employer shall ensure that employees working in and
contiguous to regulated areas comprehend the warning signs required to
be posted by paragraph (j)(3)(i) of this section. Means to ensure
employee comprehension may include the use of foreign languages,
pictographs and graphics.
(v) At the entrance to mechanical rooms/areas in which employees
reasonably can be expected to enter and which contain ACM and/or PACM,
the building owner shall post signs which identify the material which is
present, its location, and appropriate work practices which, if
followed, will ensure that ACM and/or PACM will not be disturbed. The
employer shall ensure, to the extent feasible, that employees who come
in contact with these signs can comprehend them. Means to ensure
employee comprehension may include the use of foreign languages,
pictographs, graphics, and awareness training.
(4) Warning labels--(i) Labeling. Warning labels shall be affixed to
all raw materials, mixtures, scrap, waste, debris, and other products
containing asbestos fibers, or to their containers.When a building owner
or employer identifies previously installed ACM and/or PACM, labels or
signs shall be affixed or posted so that employees will be notified of
what materials contain ACM and/or PACM. The employer shall attach such
labels in areas where they will clearly be noticed by employees who are
likely to be exposed, such as at the entrance to mechanical room/areas.
Signs required by paragraph (j)(3) of this section may be posted in lieu
of labels so long as they contain information required for labelling.
(ii) Label specifications. The labels shall comply with the
requirements of 29 CFR 1910.1200(f) of OSHA's Hazard Communication
standard, and shall include the following information:
DANGER
CONTAINS ASBESTOS FIBERS
AVOID CREATING DUST
CANCER AND LUNG DISEASE HAZARD
(5) Material safety data sheets. Employers who are manufacturers or
importers of asbestos or asbestos products
[[Page 27]]
shall comply with the requirements regarding development of material
safety data sheets as specified in 29 CFR 1910.1200(g) of OSHA's Hazard
Communication standard, except as provided by paragraph (j)(6) of this
section.
(6) The provisions for labels required by paragraph (j)(4) of this
section or for material safety data sheets required by paragraph (j)(5)
of this section do not apply where:
(i) Asbestos fibers have been modified by a bonding agent, coating,
binder, or other material provided that the manufacturer can demonstrate
that during any reasonably foreseeable use, handling, storage, disposal,
processing, or transportation, no airborne concentrations of fibers of
asbestos in excess of the TWA permissible exposure level and/or
excursion limit will be released or
(ii) Asbestos is present in a product in concentrations less than
1.0%.
(7) Employee information and training. (i) The employer shall
institute a training program for all employees who are exposed to
airborne concentrations of asbestos at or above the PEL and/or excursion
limit and ensure their participation in the program.
(ii) Training shall be provided prior to or at the time of initial
assignment and at least annually thereafter.
(iii) The training program shall be conducted in a manner which the
employee is able to understand. The employer shall ensure that each
employee is informed of the following:
(A) The health effects associated with asbestos exposure;
(B) The relationship between smoking and exposure to asbestos
producing lung cancer:
(C) The quantity, location, manner of use, release, and storage of
asbestos, and the specific nature of operations which could result in
exposure to asbestos;
(D) The engineering controls and work practices associated with the
employee's job assignment;
(E) The specific procedures implemented to protect employees from
exposure to asbestos, such as appropriate work practices, emergency and
clean-up procedures, and personal protective equipment to be used;
(F) The purpose, proper use, and limitations of respirators and
protective clothing, if appropriate;
(G) The purpose and a description of the medical surveillance
program required by paragraph (l) of this section;
(H) The content of this standard, including appendices.
(I) The names, addresses and phone numbers of public health
organizations which provide information, materials, and/or conduct
programs concerning smoking cessation. The employer may distribute the
list of such organizations contained in Appendix I to this section, to
comply with this requirement.
(J) The requirements for posting signs and affixing labels and the
meaning of the required legends for such signs and labels.
(iv) The employer shall also provide, at no cost to employees who
perform housekeeping operations in an area which contains ACM or PACM,
an asbestos awareness training course, which shall at a minimum contain
the following elements: health effects of asbestos, locations of ACM and
PACM in the building/facility, recognition of ACM and PACM damage and
deterioration, requirements in this standard relating to housekeeping,
and proper response to fiber release episodes, to all employees who
perform housekeeping work in areas where ACM and/or PACM is present.
Each such employee shall be so trained at least once a year.
(v) Access to information and training materials.
(A) The employer shall make a copy of this standard and its
appendices readily available without cost to all affected employees.
(B) The employer shall provide, upon request, all materials relating
to the employee information and training program to the Assistant
Secretary and the training program to the Assistant Secretary and the
Director.
(C) The employer shall inform all employees concerning the
availability of self-help smoking cessation program material. Upon
employee request, the employer shall distribute such material,
consisting of NIH Publication No. 89-1647, or equivalent self-help
material, which is approved or published by
[[Page 28]]
a public health organization listed in Appendix I to this section.
(8) Criteria to rebut the designation of installed material as PACM.
(i) At any time, an employer and/or building owner may demonstrate, for
purposes of this standard, that PACM does not contain asbestos. Building
owners and/or employers are not required to communicate information
about the presence of building material for which such a demonstration
pursuant to the requirements of paragraph (j)(8)(ii) of this section has
been made. However, in all such cases, the information, data and
analysis supporting the determination that PACM does not contain
asbestos, shall be retained pursuant to paragraph (m) of this section.
(ii) An employer or owner may demonstrate that PACM does not contain
asbestos by the following:
(A) Having a completed inspection conducted pursuant to the
requirements of AHERA (40 CFR 763, Subpart E) which demonstrates that no
ACM is present in the material; or
(B) Performing tests of the material containing PACM which
demonstrate that no ACM is present in the material. Such tests shall
include analysis of bulk samples collected in the manner described in 40
CFR 763.86. The tests, evaluation and sample collection shall be
conducted by an accredited inspector or by a CIH. Analysis of samples
shall be performed by persons or laboratories with proficiency
demonstrated by current successful participation in a nationally
recognized testing program such as the National Voluntary Laboratory
Accreditation Program (NVLAP) or the National Institute for Standards
and Technology (NIST) or the Round Robin for bulk samples administered
by the American Industrial Hygiene Association (AIHA) or an equivalent
nationally-recognized round robin testing program.
(iii) The employer and/or building owner may demonstrate that
flooring material including associated mastic and backing does not
contain asbestos, by a determination of an industrial hygienist based
upon recognized analytical techniques showing that the material is not
ACM.
(k) Housekeeping. (1) All surfaces shall be maintained as free as
practicable of ACM waste and debris and accompanying dust.
(2) All spills and sudden releases of material containing asbestos
shall be cleaned up as soon as possible.
(3) Surfaces contaminated with asbestos may not be cleaned by the
use of compressed air.
(4) Vacuuming. HEPA-filtered vacuuming equipment shall be used for
vacuuming asbestos containing waste and debris. The equipment shall be
used and emptied in a manner which minimizes the reentry of asbestos
into the workplace.
(5) Shoveling, dry sweeping and dry clean-up of asbestos may be used
only where vacuuming and/or wet cleaning are not feasible.
(6) Waste disposal. Waste, scrap, debris, bags, containers,
equipment, and clothing contaminated with asbestos consigned for
disposal, shall be collected, recycled and disposed of in sealed
impermeable bags, or other closed, impermeable containers.
(7) Care of asbestos-containing flooring material.
(i) Sanding of asbestos-containing floor material is prohibited.
(ii) Stripping of finishes shall be conducted using low abrasion
pads at speeds lower than 300 rpm and wet methods.
(iii) Burnishing or dry buffing may be performed only on asbestos-
containing flooring which has sufficient finish so that the pad cannot
contact the asbestos-containing material.
(8) Waste and debris and accompanying dust in an area containing
accessible ACM and/or PACM or visibly deteriorated ACM, shall not be
dusted or swept dry, or vacuumed without using a HEPA filter.
(l) Medical surveillance--(1) General--(i) Employees covered. The
employer shall institute a medical surveillance program for all
employees who are or will be exposed to airborne concentrations of
fibers of asbestos at or above the TWA and/or excursion limit.
(ii) Examination by a physician. (A) The employer shall ensure that
all medical examinations and procedures are performed by or under the
supervision of a licensed physician, and shall
[[Page 29]]
be provided without cost to the employee and at a reasonable time and
place.
(B) Persons other than licensed physicians, who administer the
pulmonary function testing required by this section, shall complete a
training course in spirometry sponsored by an appropriate academic or
professional institution.
(2) Pre-placement examinations. (i) Before an employee is assigned
to an occupation exposed to airborne concentrations of asbestos fibers
at or above the TWA and/or excursion limit, a pre-placement medical
examination shall be provided or made available by the employer.
(ii) Such examination shall include, as a minimum, a medical and
work history; a complete physical examination of all systems with
emphasis on the respiratory system, the cardiovascular system and
digestive tract; completion of the respiratory disease standardized
questionnaire in Appendix D to this section, Part 1; a chest
roentgenogram (posterior-anterior 14 x 17 inches); pulmonary function
tests to include forced vital capacity (FVC) and forced expiratory
volume at 1 second (FEV(1.0)); and any additional tests deemed
appropriate by the examining physician. Interpretation and
classification of chest roentgenogram shall be conducted in accordance
with Appendix E to this section.
(3) Periodic examinations. (i) Periodic medical examinations shall
be made available annually.
(ii) The scope of the medical examination shall be in conformance
with the protocol established in paragraph (l)(2)(ii) of this section,
except that the frequency of chest roentgenogram shall be conducted in
accordance with Table 2, and the abbreviated standardized questionnaire
contained in, Part 2 of Appendix D to this section shall be administered
to the employee.
Table 2--Frequency of Chest Roentgenogram
----------------------------------------------------------------------------------------------------------------
Age of employee
Years since first exposure --------------------------------------------------------------------------------
15 to 35 35+ to 45 45+
----------------------------------------------------------------------------------------------------------------
0 to 10........................ Every 5 years.............. Every 5 years............. Every 5 years.
10+............................ Every 5 years.............. Every 2 years............. Every 1 year.
----------------------------------------------------------------------------------------------------------------
(4) Termination of employment examinations. (i) The employer shall
provide, or make available, a termination of employment medical
examination for any employee who has been exposed to airborne
concentrations of fibers of asbestos at or above the TWA and/or
excursion limit.
(ii) The medical examination shall be in accordance with the
requirements of the periodic examinations stipulated in paragraph (l)(3)
of this section, and shall be given within 30 calendar days before or
after the date of termination of employment.
(5) Recent examinations. No medical examination is required of any
employee, if adequate records show that the employee has been examined
in accordance with any of paragraphs ((l)(2) through (l)(4)) of this
section within the past 1 year period. A pre- employment medical
examination which was required as a condition of employment by the
employer, may not be used by that employer to meet the requirements of
this paragraph, unless the cost of such examination is borne by the
employer.
(6) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this standard and Appendices D and E.
(ii) A description of the affected employee's duties as they relate
to the employee's exposure.
(iii) The employee's representative exposure level or anticipated
exposure level.
(iv) A description of any personal protective and respiratory
equipment used or to be used.
(v) Information from previous medical examinations of the affected
employee that is not otherwise available to the examining physician.
(7) Physician's written opinion. (i) The employer shall obtain a
written signed
[[Page 30]]
opinion from the examining physician. This written opinion shall contain
the results of the medical examination and shall include:
(A) The physician's opinion as to whether the employee has any
detected medical conditions that would place the employee at an
increased risk of material health impairment from exposure to asbestos;
(B) Any recommended limitations on the employee or upon the use of
personal protective equipment such as clothing or respirators;
(C) A statement that the employee has been informed by the physician
of the results of the medical examination and of any medical conditions
resulting from asbestos exposure that require further explanation or
treatment; and
(D) A statement that the employee has been informed by the physician
of the increased risk of lung cancer attributable to the combined effect
of smoking and asbestos exposure.
(ii) The employer shall instruct the physician not to reveal in the
written opinion given to the employer specific findings or diagnoses
unrelated to occupational exposure to asbestos.
(iii) The employer shall provide a copy of the physician's written
opinion to the affected employee within 30 days from its receipt.
(m) Recordkeeping--(1) Exposure measurements.
Note: The employer may utilize the services of competent
organizations such as industry trade associations and employee
associations to maintain the records required by this section.
(i) The employer shall keep an accurate record of all measurements
taken to monitor employee exposure to asbestos as prescribed in
paragraph (d) of this section.
(ii) This record shall include at least the following information:
(A) The date of measurement;
(B) The operation involving exposure to asbestos which is being
monitored;
(C) Sampling and analytical methods used and evidence of their
accuracy;
(D) Number, duration, and results of samples taken;
(E) Type of respiratory protective devices worn, if any; and
(F) Name, social security number and exposure of the employees whose
exposure are represented.
(iii) The employer shall maintain this record for at least thirty
(30) years, in accordance with 29 CFR 1910.20.
(2) Objective data for exempted operations. (i) Where the
processing, use, or handling of products made from or containing
asbestos is exempted from other requirements of this section under
paragraph (d)(2)(iii) of this section, the employer shall establish and
maintain an accurate record of objective data reasonably relied upon in
support of the exemption.
(ii) The record shall include at least the following:
(A) The product qualifying for exemption;
(B) The source of the objective data;
(C) The testing protocol, results of testing, and/or analysis of the
material for the release of asbestos;
(D) A description of the operation exempted and how the data support
the exemption; and
(E) Other data relevant to the operations, materials, processing, or
employee exposures covered by the exemption.
(iii) The employer shall maintain this record for the duration of
the employer's reliance upon such objective data.
(3) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance by paragraph (l)(1)(i) of this section, in accordance with
29 CFR 1910.20.
(ii) The record shall include at least the following information:
(A) The name and social security number of the employee;
(B) Physician's written opinions;
(C) Any employee medical complaints related to exposure to asbestos;
and
(D) A copy of the information provided to the physician as required
by paragraph (l)(6) of this section.
(iii) The employer shall ensure that this record is maintained for
the duration of employment plus thirty (30) years, in accordance with 29
CFR 1910.20.
[[Page 31]]
(4) Training. The employer shall maintain all employee training
records for one (1) year beyond the last date of employment of that
employee.
(5) Availability. (i) The employer, upon written request, shall make
all records required to be maintained by this section available to the
Assistant Secretary and the Director for examination and copying.
(ii) The employer, upon request shall make any exposure records
required by paragraph (m)(1) of this section available for examination
and copying to affected employees, former employees, designated
representatives and the Assistant Secretary, in accordance with 29 CFR
1910.20 (a) through (e) and (g) through (i).
(iii) The employer, upon request, shall make employee medical
records required by paragraph (m)(3) of this section available for
examination and copying to the subject employee, to anyone having the
specific written consent of the subject employee, and the Assistant
Secretary, in accordance with 29 CFR 1910.20.
(6) Transfer of records. (i) The employer shall comply with the
requirements concerning transfer of records set forth in 29 CFR
1910.20(h).
(ii) Whenever the employer ceases to do business and there is no
successor employer to receive and retain the records for the prescribed
period, the employer shall notify the Director at least 90 days prior to
disposal of records and, upon request, transmit them to the Director.
(n) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to asbestos conducted in accordance with paragraph (d) of this
section.
(2) Observation procedures. When observation of the monitoring of
employee exposure to asbestos requires entry into an area where the use
of protective clothing or equipment is required, the observer shall be
provided with and be required to use such clothing and equipment and
shall comply with all other applicable safety and health procedures.
(o) Dates--(1) Effective date. This standard shall become effective
October 11, 1994.
(2) The provisions of 29 CFR 1910.1001 remain in effect until the
start-up dates of the equivalent provisions of this standard.
(3) Start-up dates. All obligations of this standard commence on the
effective date except as follows:
(i) Exposure monitoring. Initial monitoring required by paragraph
(d)(2) of this section shall be completed by October 1, 1995.
(ii) Regulated areas. Regulated areas required to be established by
paragraph (e) of this section as a result of initial monitoring shall be
set up by October 1, 1995.
(iii) Respiratory protection. Respiratory protection required by
paragraph (g) of this section shall be provided by October 1, 1995.
(iv) Hygiene and lunchroom facilities. Construction plans for change
rooms, showers, lavatories, and lunchroom facilities shall be completed
by October 1, 1995.
(v) Communication of hazards. Identification, notification, labeling
and sign posting, and training required by paragraph (j) of this section
shall be provided by October 1, 1995.
(vi) Medical surveillance. Medical surveillance not previously
required by paragraph (1) of this section shall be provided by October
1, 1995.
(vii) Compliance program. Written compliance programs required by
paragraph (f)(2) of this section shall be completed and available for
inspection and copying by October 1, 1995.11
(viii) Methods of compliance. The engineering and work practice
controls as required by paragraph (f) shall be implemented by October 1,
1995.
(p) Appendices. (1) Appendices A, C, D, E, and F to this section are
incorporated as part of this section and the contents of these
Appendices are mandatory.
(2) Appendices B, G, H, I, and J to this section are informational
and are not intended to create any additional obligations not otherwise
imposed or to detract from any existing obligations.
[[Page 32]]
Appendix A to Sec. 1910.1001--OSHA Reference Method--Mandatory
This mandatory appendix specifies the procedure for analyzing air
samples for asbestos and specifies quality control procedures that must
be implemented by laboratories performing the analysis. The sampling and
analytical methods described below represent the elements of the
available monitoring methods (such as Appendix B of their regulation,
the most current version of the OSHA method ID-160, or the most current
version of the NIOSH Method 7400). All employers who are required to
conduct air monitoring under paragraph (d) of the standard are required
to utilize analytical laboratories that use this procedure, or an
equivalent method, for collecting and analyzing samples.
Sampling and Analytical Procedure
1. The sampling medium for air samples shall be mixed cellulose
ester filter membranes. These shall be designated by the manufacturer as
suitable for asbestos counting. See below for rejection of blanks.
2. The preferred collection device shall be the 25-mm diameter
cassette with an open-faced 50-mm electrically conductive extension
cowl. The 37-mm cassette may be used if necessary but only if written
justification for the need to use the 37-mm filter cassette accompanies
the sample results in the employee's exposure monitoring record. Do not
reuse or reload cassettes for asbestos sample collection.
3. An air flow rate between 0.5 liter/min and 2.5 liters/min shall
be selected for the 25-mm cassette. If the 37-mm cassette is used, an
air flow rate between 1 liter/min and 2.5 liters/min shall be selected.
4. Where possible, a sufficient air volume for each air sample shall
be collected to yield between 100 and 1,300 fibers per square millimeter
on the membrane filter. If a filter darkens in appearance or if loose
dust is seen on the filter, a second sample shall be started.
5. Ship the samples in a rigid container with sufficient packing
material to prevent dislodging the collected fibers. Packing material
that has a high electrostatic charge on its surface (e.g., expanded
polystyrene) cannot be used because such material can cause loss of
fibers to the sides of the cassette.
6. Calibrate each personal sampling pump before and after use with a
representative filter cassette installed between the pump and the
calibration devices.
7. Personal samples shall be taken in the ``breathing zone'' of the
employee (i.e., attached to or near the collar or lapel near the
worker's face).
8. Fiber counts shall be made by positive phase contrast using a
microscope with an 8 to 10 X eyepiece and a 40 to 45 X objective for a
total magnification of approximately 400 X and a numerical aperture of
0.65 to 0.75. The microscope shall also be fitted with a green or blue
filter.
9. The microscope shall be fitted with a Walton-Beckett eyepiece
graticule calibrated for a field diameter of 100 micrometers (+/-2
micrometers).
10. The phase-shift detection limit of the microscope shall be about
3 degrees measured using the HSE phase shift test slide as outlined
below.
a. Place the test slide on the microscope stage and center it under
the phase objective.
b. Bring the blocks of grooved lines into focus.
Note: The slide consists of seven sets of grooved lines (ca. 20
grooves to each block) in descending order of visibility from sets 1 to
7, seven being the least visible. The requirements for asbestos counting
are that the microscope optics must resolve the grooved lines in set 3
completely, although they may appear somewhat faint, and that the
grooved lines in sets 6 and 7 must be invisible. Sets 4 and 5 must be at
least partially visible but may vary slightly in visibility between
microscopes. A microscope that fails to meet these requirements has
either too low or too high a resolution to be used for asbestos
counting.
c. If the image deteriorates, clean and adjust the microscope
optics. If the problem persists, consult the microscope manufacturer.
11. Each set of samples taken will include 10% field blanks or a
minimum of 2 field blanks. These blanks must come from the same lot as
the filters used for sample collection. The field blank results shall be
averaged and subtracted from the analytical results before reporting. A
set consists of any sample or group of samples for which an evaluation
for this standard must be made. Any samples represented by a field blank
having a fiber count in excess of the detection limit of the method
being used shall be rejected.
12. The samples shall be mounted by the acetone/triacetin method or
a method with an equivalent index of refraction and similar clarity.
13. Observe the following counting rules.
a. Count only fibers equal to or longer than 5 micrometers. Measure
the length of curved fibers along the curve.
b. In the absence of other information, count all particles as
asbesto that have a length-to-width ratio (aspect ratio) of 3:1 or
greater.
c. Fibers lying entirely within the boundary of the Walton-Beckett
graticule field shall receive a count of 1. Fibers crossing the boundary
once, having one end within the circle, shall receive the count of one
half (\1/2\). Do not count any fiber that crosses the graticule boundary
more than once. Reject
[[Page 33]]
and do not count any other fibers even though they may be visible
outside the graticule area.
d. Count bundles of fibers as one fiber unless individual fibers can
be identified by observing both ends of an individual fiber.
e. Count enough graticule fields to yield 100 fibers. Count a
minimum of 20 fields; stop counting at 100 fields regardless of fiber
count.
14. Blind recounts shall be conducted at the rate of 10 percent.
Quality Control Procedures
1. Intralaboratory program. Each laboratory and/or each company with
more than one microscopist counting slides shall establish a
statistically designed quality assurance program involving blind
recounts and comparisons between microscopists to monitor the
variability of counting by each microscopist and between microscopists.
In a company with more than one laboratory, the program shall include
all laboratories and shall also evaluate the laboratory-to-laboratory
variability.
2.a. Interlaboratory program. Each laboratory analyzing asbestos
samples for compliance determination shall implement an interlaboratory
quality assurance program that as a minimum includes participation of at
least two other independent laboratories. Each laboratory shall
participate in round robin testing at least once every 6 months with at
least all the other laboratories in its interlaboratory quality
assurance group. Each laboratory shall submit slides typical of its own
work load for use in this program. The round robin shall be designed and
results analyzed using appropriate statistical methodology.
2.b. All laboratories should also participate in a national sample
testing scheme such as the Proficiency Analytical Testing Program (PAT),
or the Asbestos Registry sponsored by the American Industrial Hygiene
Association (AIHA).
3. All individuals performing asbestos analysis must have taken the
NIOSH course for sampling and evaluating airborne asbestos dust or an
equalivalent course.
4. When the use of different microscopes contributes to differences
between counters and laboratories, the effect of the different
microscope shall be evaluated and the microscope shall be replaced, as
necessary.
5. Current results of these quality assurance programs shall be
posted in each laboratory to keep the microscopists informed.
Appendix B to Sec. 1910.1001--Detailed Procedures for Asbestos Sampling
and Analysis--Non-mandatory
Matrix Air:
OSHA Permissible Exposure Limits:
Time Weighted Average.............. 0.1 fiber/cc
Excursion Level (30 minutes)....... 1.0 fiber/cc
Collection Procedure:
A known volume of air is drawn through a 25-mm diameter cassette
containing a mixed-cellulose ester filter. The cassette must be equipped
with an electrically conductive 50-mm extension cowl. The sampling time
and rate are chosen to give a fiber density of between 100 to 1,300
fibers/mm2 on the filter.
Recommended Sampling Rate.............. 0.5 to 5.0 liters/minute (L/
min)
Recommended Air Volumes:
Minimum............................ 25 L
Maximum............................ 2,400 L
------------------------------------------------------------------------
Analytical Procedure: A portion of the sample filter is cleared and
prepared for asbestos fiber counting by Phase Contrast Microscopy (PCM)
at 400X.
Commercial manufacturers and products mentioned in this method are
for descriptive use only and do not constitute endorsements by USDOL-
OSHA. Similar products from other sources can be substituted.
1. Introduction
This method describes the collection of airborne asbestos fibers
using calibrated sampling pumps with mixed-cellulose ester (MCE) filters
and analysis by phase contrast microscopy (PCM). Some terms used are
unique to this method and are defined below:
Asbestos: A term for naturally occurring fibrous minerals. Asbestos
includes chrysotile, crocidolite, amosite (cummingtonite-grunerite
asbestos), tremolite asbestos, actinolite asbestos, anthophyllite
asbestos, and any of these minerals that have been chemically treated
and/or altered. The precise chemical formulation of each species will
vary with the location from which it was mined. Nominal compositions are
listed:
Chrysotile................................ Mg3 Si2 O5(OH)4
Crocidolite............................... Na2 Fe32+ Fe23 + Si8 O22
(OH)2
Amosite................................... (Mg,Fe)7 Si8 O22 (OH)2
Tremolite-actinolite...................... Ca2(Mg,Fe)5 Si8 O22 (OH)2
Anthophyllite............................. (Mg,Fe)7 Si8 O22 (OH)2
Asbestos Fiber: A fiber of asbestos which meets the criteria
specified below for a fiber.
Aspect Ratio: The ratio of the length of a fiber to it's diameter
(e.g. 3:1, 5:1 aspect ratios).
Cleavage Fragments: Mineral particles formed by comminution of
minerals, especially those characterized by parallel sides and a
moderate aspect ratio (usually less than 20:1).
Detection Limit: The number of fibers necessary to be 95% certain
that the result is greater than zero.
[[Page 34]]
Differential Counting: The term applied to the practice of excluding
certain kinds of fibers from the fiber count because they do not appear
to be asbestos.
Fiber: A particle that is 5 m or longer, with a length-to-
width ratio of 3 to 1 or longer.
Field: The area within the graticule circle that is superimposed on
the microscope image.
Set: The samples which are taken, submitted to the laboratory,
analyzed, and for which, interim or final result reports are generated.
Tremolite, Anthophyllite, and Actinolite: The non-asbestos form of
these minerals which meet the definition of a fiber. It includes any of
these minerals that have been chemically treated and/or altered.
Walton-Beckett Graticule: An eyepiece graticule specifically
designed for asbestos fiber counting. It consists of a circle with a
projected diameter of 100 2 m (area of about 0.00785
mm2) with a crosshair having tic-marks at 3-m
intervals in one direction and 5-m in the orthogonal direction.
There are marks around the periphery of the circle to demonstrate the
proper sizes and shapes of fibers. This design is reproduced in Figure
1. The disk is placed in one of the microscope eyepieces so that the
design is superimposed on the field of view.
1.1. History
Early surveys to determine asbestos exposures were conducted using
impinger counts of total dust with the counts expressed as million
particles per cubic foot. The British Asbestos Research Council
recommended filter membrane counting in 1969. In July 1969, the Bureau
of Occupational Safety and Health published a filter membrane method for
counting asbestos fibers in the United States. This method was refined
by NIOSH and published as P CAM 239. On May 29, 1971, OSHA specified
filter membrane sampling with phase contrast counting for evaluation of
asbestos exposures at work sites in the United States. The use of this
technique was again required by OSHA in 1986. Phase contrast microscopy
has continued to be the method of choice for the measurement of
occupational exposure to asbestos.
1.2. Principle
Air is drawn through a MCE filter to capture airborne asbestos
fibers. A wedge shaped portion of the filter is removed, placed on a
glass microscope slide and made transparent. A measured area (field) is
viewed by PCM. All the fibers meeting defined criteria for asbestos are
counted and considered a measure of the airborne asbestos concentration.
1.3. Advantages and Disadvantages
There are four main advantages of PCM over other methods:
(1) The technique is specific for fibers. Phase contrast is a fiber
counting technique which excludes non-fibrous particles from the
analysis.
(2) The technique is inexpensive and does not require specialized
knowledge to carry out the analysis for total fiber counts.
(3) The analysis is quick and can be performed on-site for rapid
determination of air concentrations of asbestos fibers.
(4) The technique has continuity with historical epidemiological
studies so that estimates of expected disease can be inferred from long-
term determinations of asbestos exposures.
The main disadvantage of PCM is that it does not positively identify
asbestos fibers. Other fibers which are not asbestos may be included in
the count unless differential counting is performed. This requires a
great deal of experience to adequately differentiate asbestos from non-
asbestos fibers. Positive identification of asbestos must be performed
by polarized light or electron microscopy techniques. A further
disadvantage of PCM is that the smallest visible fibers are about 0.2
m in diameter while the finest asbestos fibers may be as small
as 0.02 m in diameter. For some exposures, substantially more
fibers may be present than are actually counted.
1.4. Workplace Exposure
Asbestos is used by the construction industry in such products as
shingles, floor tiles, asbestos cement, roofing felts, insulation and
acoustical products. Non-construction uses include brakes, clutch
facings, paper, paints, plastics, and fabrics. One of the most
significant exposures in the workplace is the removal and encapsulation
of asbestos in schools, public buildings, and homes. Many workers have
the potential to be exposed to asbestos during these operations.
About 95% of the asbestos in commercial use in the United States is
chrysotile. Crocidolite and amosite make up most of the remainder.
Anthophyllite and tremolite or actinolite are likely to be encountered
as contaminants in various industrial products.
1.5. Physical Properties
Asbestos fiber possesses a high tensile strength along its axis, is
chemically inert, non-combustible, and heat resistant. It has a high
electrical resistance and good sound absorbing properties. It can be
weaved into cables, fabrics or other textiles, and also matted into
asbestos papers, felts, or mats.
2. Range and Detection Limit
2.1. The ideal counting range on the filter is 100 to 1,300 fibers/
mm\2\. With a Walton-
[[Page 35]]
Beckett graticule this range is equivalent to 0.8 to 10 fibers/field.
Using NIOSH counting statistics, a count of 0.8 fibers/field would give
an approximate coefficient of variation (CV) of 0.13.
2.2. The detection limit for this method is 4.0 fibers per 100
fields or 5.5 fibers/mm\2\. This was determined using an equation to
estimate the maximum CV possible at a specific concentration (95%
confidence) and a Lower Control Limit of zero. The CV value was then
used to determine a corresponding concentration from historical CV vs
fiber relationships. As an example:
Lower Control Limit (95% Confidence) = AC - 1.645(CV)(AC)
Where:
AC = Estimate of the airborne fiber concentration (fibers/cc) Setting
the Lower Control Limit = 0 and solving for CV:
0 = AC - 1.645(CV)(AC)
CV = 0.61
This value was compared with CV vs. count curves. The count at which
CV = 0.61 for Leidel-Busch counting statistics or for an OSHA Salt Lake
Technical Center (OSHA-SLTC) CV curve (see Appendix A for further
information) was 4.4 fibers or 3.9 fibers per 100 fields, respectively.
Although a lower detection limit of 4 fibers per 100 fields is supported
by the OSHA-SLTC data, both data sets support the 4.5 fibers per 100
fields value.
3. Method Performance--Precision and Accuracy
Precision is dependent upon the total number of fibers counted and
the uniformity of the fiber distribution on the filter. A general rule
is to count at least 20 and not more than 100 fields. The count is
discontinued when 100 fibers are counted, provided that 20 fields have
already been counted. Counting more than 100 fibers results in only a
small gain in precision. As the total count drops below 10 fibers, an
accelerated loss of precision is noted.
At this time, there is no known method to determine the absolute
accuracy of the asbestos analysis. Results of samples prepared through
the Proficiency Analytical Testing (PAT) Program and analyzed by the
OSHA-SLTC showed no significant bias when compared to PAT reference
values. The PAT samples were analyzed from 1987 to 1989 (N=36) and the
concentration range was from 120 to 1,300 fibers/mm\2\.
4. Interferences
Fibrous substances, if present, may interfere with asbestos
analysis.
Some common fibers are:
fiberglass
anhydrite
plant fibers
perlite veins
gypsum
some synthetic fibers
membrane structures
sponge spicules
diatoms
microorganisms
wollastonite
The use of electron microscopy or optical tests such as polarized
light, and dispersion staining may be used to differentiate these
materials from asbestos when necessary.
5. Sampling
5.1. Equipment
5.1.1. Sample assembly (The assembly is shown in Figure 3).
Conductive filter holder consisting of a 25-mm diameter, 3-piece
cassette having a 50-mm long electrically conductive extension cowl.
Backup pad, 25-mm, cellulose. Membrane filter, mixed-cellulose ester
(MCE), 25-mm, plain, white, 0.4 to 1.2-m pore size.
Notes: (a) Do not re-use cassettes.
(b) Fully conductive cassettes are required to reduce fiber loss to
the sides of the cassette due to electrostatic attraction.
(c) Purchase filters which have been selected by the manufacturer
for asbestos counting or analyze representative filters for fiber
background before use. Discard the filter lot if more than 4 fibers/100
fields are found.
(d) To decrease the possibility of contamination, the sampling
system (filter-backup pad-cassette) for asbestos is usually preassembled
by the manufacturer.
(e) Other cassettes, such as the Bell-mouth, may be used within the
limits of their validation.
5.1.2. Gel bands for sealing cassettes.
5.1.3. Sampling pump.
Each pump must be a battery operated, self-contained unit small
enough to be placed on the monitored employee and not interfere with the
work being performed. The pump must be capable of sampling at the
collection rate for the required sampling time.
5.1.4. Flexible tubing, 6-mm bore.
5.1.5. Pump calibration.
Stopwatch and bubble tube/burette or electronic meter.
5.2. Sampling Procedure
5.2.1. Seal the point where the base and cowl of each cassette meet
with a gel band or tape.
5.2.2. Charge the pumps completely before beginning.
5.2.3. Connect each pump to a calibration cassette with an
appropriate length of 6-mm bore plastic tubing. Do not use luer
connectors--the type of cassette specified above has built-in adapters.
5.2.4. Select an appropriate flow rate for the situation being
monitored. The sampling flow rate must be between 0.5 and 5.0 L/min for
personal sampling and is commonly set
[[Page 36]]
between 1 and 2 L/min. Always choose a flow rate that will not produce
overloaded filters.
5.2.5. Calibrate each sampling pump before and after sampling with a
calibration cassette in-line (Note: This calibration cassette should be
from the same lot of cassettes used for sampling). Use a primary
standard (e.g. bubble burette) to calibrate each pump. If possible,
calibrate at the sampling site.
Note: If sampling site calibration is not possible, environmental
influences may affect the flow rate. The extent is dependent on the type
of pump used. Consult with the pump manufacturer to determine dependence
on environmental influences. If the pump is affected by temperature and
pressure changes, correct the flow rate using the formula shown in the
section ``Sampling Pump Flow Rate Corrections'' at the end of this
appendix.
5.2.6. Connect each pump to the base of each sampling cassette with
flexible tubing. Remove the end cap of each cassette and take each air
sample open face. Assure that each sample cassette is held open side
down in the employee's breathing zone during sampling. The distance from
the nose/mouth of the employee to the cassette should be about 10 cm.
Secure the cassette on the collar or lapel of the employee using spring
clips or other similar devices.
5.2.7. A suggested minimum air volume when sampling to determine TWA
compliance is 25 L. For Excursion Limit (30 min sampling time)
evaluations, a minimum air volume of 48 L is recommended.
5.2.8. The most significant problem when sampling for asbestos is
overloading the filter with non-asbestos dust. Suggested maximum air
sample volumes for specific environments are:
------------------------------------------------------------------------
Environment Air vol. (L)
------------------------------------------------------------------------
Asbestos removal operations (visible dust).. 100
Asbestos removal operations (little dust)... 240
Office environments......................... 400
to
2,400
------------------------------------------------------------------------
Caution: Do not overload the filter with dust. High levels of non-
fibrous dust particles may obscure fibers on the filter and lower the
count or make counting impossible. If more than about 25 to 30% of the
field area is obscured with dust, the result may be biased low. Smaller
air volumes may be necessary when there is excessive non-asbestos dust
in the air.
While sampling, observe the filter with a small flashlight. If there
is a visible layer of dust on the filter, stop sampling, remove and seal
the cassette, and replace with a new sampling assembly. The total dust
loading should not exceed 1 mg.
5.2.9. Blank samples are used to determine if any contamination has
occurred during sample handling. Prepare two blanks for the first 1 to
20 samples. For sets containing greater than 20 samples, prepare blanks
as 10% of the samples. Handle blank samples in the same manner as air
samples with one exception: Do not draw any air through the blank
samples. Open the blank cassette in the place where the sample cassettes
are mounted on the employee. Hold it open for about 30 seconds. Close
and seal the cassette appropriately. Store blanks for shipment with the
sample cassettes.
5.2.10. Immediately after sampling, close and seal each cassette
with the base and plastic plugs. Do not touch or puncture the filter
membrane as this will invalidate the analysis.
5.2.11 Attach and secure a sample seal around each sample cassette
in such a way as to assure that the end cap and base plugs cannot be
removed without destroying the seal. Tape the ends of the seal together
since the seal is not long enough to be wrapped end-to-end. Also wrap
tape around the cassette at each joint to keep the seal secure.
5.3. Sample Shipment
5.3.1. Send the samples to the laboratory with paperwork requesting
asbestos analysis. List any known fibrous interferences present during
sampling on the paperwork. Also, note the workplace operation(s)
sampled.
5.3.2. Secure and handle the samples in such that they will not
rattle during shipment nor be exposed to static electricity. Do not ship
samples in expanded polystyrene peanuts, vermiculite, paper shreds, or
excelsior. Tape sample cassettes to sheet bubbles and place in a
container that will cushion the samples in such a manner that they will
not rattle.
5.3.3. To avoid the possibility of sample contamination, always ship
bulk samples in separate mailing containers.
6. Analysis
6.1. Safety Precautions
6.1.1. Acetone is extremely flammable and precautions must be taken
not to ignite it. Avoid using large containers or quantities of acetone.
Transfer the solvent in a ventilated laboratory hood. Do not use acetone
near any open flame. For generation of acetone vapor, use a spark free
heat source.
6.1.2. Any asbestos spills should be cleaned up immediately to
prevent dispersal of fibers. Prudence should be exercised to avoid
contamination of laboratory facilities or exposure of personnel to
asbestos. Asbestos spills should be cleaned up with wet methods and/or a
High Efficiency Particulate-Air (HEPA) filtered vacuum.
Caution: Do not use a vacuum without a HEPA filter--It will disperse
fine asbestos fibers in the air.
[[Page 37]]
6.2. Equipment
6.2.1. Phase contrast microscope with binocular or trinocular head.
6.2.2. Widefield or Huygenian 10X eyepieces (Note: The eyepiece
containing the graticule must be a focusing eyepiece. Use a 40X phase
objective with a numerical aperture of 0.65 to 0.75).
6.2.3. Kohler illumination (if possible) with green or blue filter.
6.2.4. Walton-Beckett Graticule, type G-22 with 100 2
m projected diameter.
6.2.5. Mechanical stage.
A rotating mechanical stage is convenient for use with polarized
light.
6.2.6. Phase telescope.
6.2.7. Stage micrometer with 0.01-mm subdivisions.
6.2.8. Phase-shift test slide, mark II (Available from PTR optics
Ltd., and also McCrone).
6.2.9. Precleaned glass slides, 25 mm X 75 mm. One end can be
frosted for convenience in writing sample numbers, etc., or paste-on
labels can be used.
6.2.10. Cover glass #1 \1/2\.
6.2.11. Scalpel (#10, curved blade).
6.2.12. Fine tipped forceps.
6.2.13. Aluminum block for clearing filter (see Appendix D and
Figure 4).
6.2.14. Automatic adjustable pipette, 100- to 500- L.
6.2.15. Micropipette, 5 L.
6.3. Reagents
6.3.1. Acetone (HPLC grade).
6.3.2. Triacetin (glycerol triacetate).
6.3.3. Lacquer or nail polish.
6.4. Standard Preparation
A way to prepare standard asbestos samples of known concentration
has not been developed. It is possible to prepare replicate samples of
nearly equal concentration. This has been performed through the PAT
program. These asbestos samples are distributed by the AIHA to
participating laboratories.
Since only about one-fourth of a 25-mm sample membrane is required
for an asbestos count, any PAT sample can serve as a ``standard'' for
replicate counting.
6.5. Sample Mounting
Note: See Safety Precautions in Section 6.1. before proceeding. The
objective is to produce samples with a smooth (non-grainy) background in
a medium with a refractive index of approximately 1.46. The technique
below collapses the filter for easier focusing and produces permanent
mounts which are useful for quality control and interlaboratory
comparison.
An aluminum block or similar device is required for sample
preparation.
6.5.1. Heat the aluminum block to about 70 deg.C. The hot block
should not be used on any surface that can be damaged by either the heat
or from exposure to acetone.
6.5.2. Ensure that the glass slides and cover glasses are free of
dust and fibers.
6.5.3. Remove the top plug to prevent a vacuum when the cassette is
opened. Clean the outside of the cassette if necessary. Cut the seal
and/or tape on the cassette with a razor blade. Very carefully separate
the base from the extension cowl, leaving the filter and backup pad in
the base.
6.5.4. With a rocking motion cut a triangular wedge from the filter
using the scalpel. This wedge should be one-sixth to one-fourth of the
filter. Grasp the filter wedge with the forceps on the perimeter of the
filter which was clamped between the cassette pieces. DO NOT TOUCH the
filter with your finger. Place the filter on the glass slide sample side
up. Static electricity will usually keep the filter on the slide until
it is cleared.
6.5.5. Place the tip of the micropipette containing about 200
L acetone into the aluminum block. Insert the glass slide into
the receiving slot in the aluminum block. Inject the acetone into the
block with slow, steady pressure on the plunger while holding the
pipette firmly in place. Wait 3 to 5 seconds for the filter to clear,
then remove the pipette and slide from the aluminum block.
6.5.6. Immediately (less than 30 seconds) place 2.5 to 3.5
L of triacetin on the filter (Note: Waiting longer than 30 seconds will
result in increased index of refraction and decreased contrast between
the fibers and the preparation. This may also lead to separation of the
cover slip from the slide).
6.5.7. Lower a cover slip gently onto the filter at a slight angle
to reduce the possibility of forming air bubbles. If more than 30
seconds have elapsed between acetone exposure and triacetin application,
glue the edges of the cover slip to the slide with lacquer or nail
polish.
6.5.8. If clearing is slow, warm the slide for 15 min on a hot plate
having a surface temperature of about 50 deg.C to hasten clearing. The
top of the hot block can be used if the slide is not heated too long.
6.5.9. Counting may proceed immediately after clearing and mounting
are completed.
6.6. Sample Analysis
Completely align the microscope according to the manufacturer's
instructions. Then, align the microscope using the following general
alignment routine at the beginning of every counting session and more
often if necessary.
6.6.1. Alignment
(1) Clean all optical surfaces. Even a small amount of dirt can
significantly degrade the image.
(2) Rough focus the objective on a sample.
[[Page 38]]
(3) Close down the field iris so that it is visible in the field of
view. Focus the image of the iris with the condenser focus. Center the
image of the iris in the field of view.
(4) Install the phase telescope and focus on the phase rings.
Critically center the rings. Misalignment of the rings results in
astigmatism which will degrade the image.
(5) Place the phase-shift test slide on the microscope stage and
focus on the lines. The analyst must see line set 3 and should see at
least parts of 4 and 5 but, not see line set 6 or 6. A microscope/
microscopist combination which does not pass this test may not be used.
6.6.2. Counting Fibers
(1) Place the prepared sample slide on the mechanical stage of the
microscope. Position the center of the wedge under the objective lens
and focus upon the sample.
(2) Start counting from one end of the wedge and progress along a
radial line to the other end (count in either direction from perimeter
to wedge tip). Select fields randomly, without looking into the
eyepieces, by slightly advancing the slide in one direction with the
mechanical stage control.
(3) Continually scan over a range of focal planes (generally the
upper 10 to 15 m of the filter surface) with the fine focus
control during each field count. Spend at least 5 to 15 seconds per
field.
(4) Most samples will contain asbestos fibers with fiber diameters
less than 1 m. Look carefully for faint fiber images. The
small diameter fibers will be very hard to see. However, they are an
important contribution to the total count.
(5) Count only fibers equal to or longer than 5 m. Measure
the length of curved fibers along the curve.
(6) Count fibers which have a length to width ratio of 3:1 or
greater.
(7) Count all the fibers in at least 20 fields. Continue counting
until either 100 fibers are counted or 100 fields have been viewed;
whichever occurs first. Count all the fibers in the final field.
(8) Fibers lying entirely within the boundary of the Walton-Beckett
graticule field shall receive a count of 1. Fibers crossing the boundary
once, having one end within the circle shall receive a count of \1/2\.
Do not count any fiber that crosses the graticule boundary more than
once. Reject and do not count any other fibers even though they may be
visible outside the graticule area. If a fiber touches the circle, it is
considered to cross the line.
(9) Count bundles of fibers as one fiber unless individual fibers
can be clearly identified and each individual fiber is clearly not
connected to another counted fiber. See Figure 1 for counting
conventions.
(10) Record the number of fibers in each field in a consistent way
such that filter non-uniformity can be assessed.
(11) Regularly check phase ring alignment.
(12) When an agglomerate (mass of material) covers more than 25% of
the field of view, reject the field and select another. Do not include
it in the number of fields counted.
(13) Perform a ``blind recount'' of 1 in every 10 filter wedges
(slides). Re-label the slides using a person other than the original
counter.
6.7. Fiber Identification
As previously mentioned in Section 1.3., PCM does not provide
positive confirmation of asbestos fibers. Alternate differential
counting techniques should be used if discrimination is desirable.
Differential counting may include primary discrimination based on
morphology, polarized light analysis of fibers, or modification of PCM
data by Scanning Electron or Transmission Electron Microscopy.
A great deal of experience is required to routinely and correctly
perform differential counting. It is discouraged unless it is legally
necessary. Then, only if a fiber is obviously not asbestos should it be
excluded from the count. Further discussion of this technique can be
found in reference 8.10.
If there is a question whether a fiber is asbestos or not, follow
the rule:
``WHEN IN DOUBT, COUNT.''
6.8. Analytical Recommendations--Quality Control System
6.8.1. All individuals performing asbestos analysis must have taken
the NIOSH course for sampling and evaluating airborne asbestos or an
equivalent course.
6.8.2. Each laboratory engaged in asbestos counting shall set up a
slide trading arrangement with at least two other laboratories in order
to compare performance and eliminate inbreeding of error. The slide
exchange occurs at least semiannually. The round robin results shall be
posted where all analysts can view individual analyst's results.
6.8.3. Each laboratory engaged in asbestos counting shall
participate in the Proficiency Analytical Testing Program, the Asbestos
Analyst Registry or equivalent.
6.8.4. Each analyst shall select and count prepared slides from a
``slide bank''. These are quality assurance counts. The slide bank shall
be prepared using uniformly distributed samples taken from the workload.
Fiber densities should cover the entire range routinely analyzed by the
laboratory. These slides are counted blind by all counters to establish
an original standard deviation. This historical distribution is compared
with the quality assurance counts. A counter must have 95% of all
quality control samples counted within three standard deviations of the
historical mean. This count is then integrated into a
[[Page 39]]
new historical mean and standard deviation for the slide.
The analyses done by the counters to establish the slide bank may be
used for an interim quality control program if the data are treated in a
proper statistical fashion.
7. Calculations
7.1. Calculate the estimated airborne asbestos fiber concentration
on the filter sample using the following formula:
where:
AC = Airborne fiber concentration
[GRAPHIC] [TIFF OMITTED] TR10AU94.000
FB = Total number of fibers greater than 5 m counted
FL = Total number of fields counted on the filter
BFB = Total number of fibers greater than 5 m counted in the
blank
BFL = Total number of fields counted on the blank
ECA = Effective collecting area of filter (385 mm\2\ nominal for a 25-mm
filter.)
FR = Pump flow rate (L/min)
MFA = Microscope count field area (mm\2\). This is 0.00785 mm\2\ for a
Walton-Beckett Graticule.
T = Sample collection time (min)
1,000 = Conversion of L to cc
Note: The collection area of a filter is seldom equal to 385 mm\2\.
It is appropriate for laboratories to routinely monitor the exact
diameter using an inside micrometer. The collection area is calculated
according to the formula:
Area = (d/2)\2\
7.2. Short-cut Calculation
Since a given analyst always has the same interpupillary distance,
the number of fields per filter for a particular analyst will remain
constant for a given size filter. The field size for that analyst is
constant (i.e. the analyst is using an assigned microscope and is not
changing the reticle).
For example, if the exposed area of the filter is always 385 mm\2\
and the size of the field is always 0.00785 mm\2\, the number of fields
per filter will always be 49,000. In addition it is necessary to convert
liters of air to cc. These three constants can then be combined such
that ECA/(1,000 X MFA)=49. The previous equation simplifies to:
[GRAPHIC] [TIFF OMITTED] TR10AU94.001
7.3. Recount Calculations
As mentioned in step 13 of Section 6.6.2., a ``blind recount'' of
10% of the slides is performed. In all cases, differences will be
observed between the first and second counts of the same filter wedge.
Most of these differences will be due to chance alone, that is, due to
the random variability (precision) of the count method. Statistical
recount criteria enables one to decide whether observed differences can
be explained due to chance alone or are probably due to systematic
differences between analysts, microscopes, or other biasing factors.
The following recount criterion is for a pair of counts that
estimate AC in fibers/cc. The criterion is given at the type-I error
level. That is, there is 5% maximum risk that we will reject a pair of
counts for the reason that one might be biased, when the large observed
difference is really due to chance.
Reject a pair of counts if:
[GRAPHIC] [TIFF OMITTED] TR29JN95.000
Where:
AC1=lower estimated airborne fiber concentration
AC2=higher estimated airborne fiber concentration
ACavg=average of the two concentration estimates
CVFB=CV for the average of the two concentration
estimates
If a pair of counts are rejected by this criterion then, recount the
rest of the filters in the submitted set. Apply the test and reject any
other pairs failing the test. Rejection shall include a memo to the
industrial hygienist stating that the sample failed a statistical test
for homogeneity and the true air concentration may be significantly
different than the reported value.
7.4. Reporting Results
Report results to the industrial hygienist as fibers/cc. Use two
significant figures. If multiple analyses are performed on a sample, an
average of the results is to be reported unless any of the results can
be rejected for cause.
8. References
8.1. Dreesen, W.C., et al, U.S. Public Health Service: A Study of
Asbestosis in the Asbestos Textile Industry, (Public Health Bulletin No.
241), US Treasury Dept., Washington, DC, 1938.
[[Page 40]]
8.2. Asbestos Research Council: The Measurement of Airborne Asbestos
Dust by the Membrane Filter Method (Technical Note), Asbestos Research
Council, Rockdale, Lancashire, Great Britain, 1969.
8.3. Bayer, S.G., Zumwalde, R.D., Brown, T.A., Equipment and
Procedure for Mounting Millipore Filters and Counting Asbestos Fibers by
Phase Contrast Microscopy, Bureau of Occupational Health, U.S. Dept. of
Health, Education and Welfare, Cincinnati, OH, 1969.
8.4. NIOSH Manual of Analytical Methods, 2nd ed., Vol. 1 (DHEW/NIOSH
Pub. No. 77-157-A). National Institute for Occupational Safety and
Health, Cincinnati, OH, 1977. pp. 239-1-239-21.
8.5. Asbestos, Code of Federal Regulations 29 CFR 1910.1001. 1971.
8.6. Occupational Exposure to Asbestos, Tremolite, Anthophyllite,
and Actinolite. Final Rule, Federal Register 51:119 (20 June 1986).
pp.22612-22790.
8.7. Asbestos, Tremolite, Anthophyllite, and Actinolite, Code of
Federal Regulations 1910.1001. 1988. pp 711-752.
8.8. Criteria for a Recommended Standard--Occupational Exposure to
Asbestos (DHEW/NIOSH Pub. No. HSM 72-10267), National Institute for
Occupational Safety and Health NIOSH, Cincinnati,OH, 1972. pp. III-1-
III-24.
8.9. Leidel, N.A., Bayer,S.G., Zumwalde, R.D.,Busch, K.A., USPHS/
NIOSH Membrane Filter Method for Evaluating Airborne Asbestos Fibers
(DHEW/NIOSH Pub. No. 79-127). National Institute for Occupational Safety
and Health, Cincinnati, OH, 1979.
8.10. Dixon, W.C., Applications of Optical Microscopy in Analysis of
Asbestos and Quartz, Analytical Techniques in Occupational Health
Chemistry, edited by D.D. Dollberg and A.W. Verstuyft. Wash. DC:
American Chemical Society, (ACS Symposium Series 120) 1980. pp. 13-41.
Quality Control
The OSHA asbestos regulations require each laboratory to establish a
quality control program. The following is presented as an example of how
the OSHA-SLTC constructed its internal CV curve as part of meeting this
requirement. Data is from 395 samples collected during OSHA compliance
inspections and analyzed from October 1980 through April 1986.
Each sample was counted by 2 to 5 different counters independently
of one another. The standard deviation and the CV statistic was
calculated for each sample. This data was then plotted on a graph of CV
vs. fibers/mm2. A least squares regression was performed
using the following equation:
CV =
antilog110[A(log10(x))2+B(log10
(x))+C]
where:
x = the number of fibers/mm2
Application of least squares gave:
A = 0.182205
B = -0.973343
C = 0.327499
Using these values, the equation becomes:
CV = antilog10 [0.182205(log10
(x))2-0.973343(log10 (x))+0.327499]
Sampling Pump Flow Rate Corrections
This correction is used if a difference greater than 5% in ambient
temperature and/or pressure is noted between calibration and sampling
sites and the pump does not compensate for the differences.
[GRAPHIC] [TIFF OMITTED] TR10AU94.003
Where:
Qact = actual flow rate
Qcal = calibrated flow rate (if a rotameter was used, the
rotameter value)
Pcal = uncorrected air pressure at calibration
Pact = uncorrected air pressure at sampling site
Tact = temperature at sampling site (K)
Tcal = temperature at calibration (K)
Walton-Beckett Graticule
When ordering the Graticule for asbestos counting, specify the exact
disc diameter needed to fit the ocular of the microscope and the
diameter (mm) of the circular counting area. Instructions for measuring
the dimensions necessary are listed:
(1) Insert any available graticule into the focusing eyepiece and
focus so that the graticule lines are sharp and clear.
(2) Align the microscope.
(3) Place a stage micrometer on the microscope object stage and
focus the microscope on the graduated lines.
(4) Measure the magnified grid length, PL ( m), using the
stage micrometer.
(5) Remove the graticule from the microscope and measure its actual
grid length, AL (mm). This can be accomplished by using a mechanical
stage fitted with verniers, or a jeweler's loupe with a direct reading
scale.
(6) Let D=100 m. Calculate the circle diameter,
dc (mm), for the Walton-Beckett graticule and specify the
diameter when making a purchase:
[GRAPHIC] [TIFF OMITTED] TR10AU94.004
Example: If PL=108 m, AL=2.93 mm and D=100 m, then,
[GRAPHIC] [TIFF OMITTED] TR10AU94.005
(7) Each eyepiece-objective-reticle combination on the microscope
must be calibrated. Should any of the three be changed
[[Page 41]]
(by zoom adjustment, disassembly, replacement, etc.), the combination
must be recalibrated. Calibration may change if interpupillary distance
is changed. Measure the field diameter, D (acceptable range:
1002 m) with a stage micrometer upon receipt of
the graticule from the manufacturer. Determine the field area
(mm2).
Field Area = (D/2)2
If D=100 m=0.1 mm, then
Field Area=(0.1 mm/2)2=0.00785 mm2
The Graticule is available from: Graticules Ltd., Morley Road,
Tonbridge TN9 IRN, Kent, England (Telephone 011-44-732-359061). Also
available from PTR Optics Ltd., 145 Newton Street, Waltham, MA 02154
[telephone (617) 891-6000] or McCrone Accessories and Components, 2506
S. Michigan Ave., Chicago, IL 60616 [phone (312)-842-7100]. The
graticule is custom made for each microscope.
Counts for the Fibers in the Figure
------------------------------------------------------------------------
Structure No. Count Explanation
------------------------------------------------------------------------
1 to 6...................... 1 Single fibers all contained
within the circle.
7........................... \1/2\ Fiber crosses circle once.
8........................... 0 Fiber too short.
9........................... 2 Two crossing fibers.
10........................... 0 Fiber outside graticule.
11........................... 0 Fiber crosses graticule twice.
12........................... \1/2\ Although split, fiber only
crosses once.
------------------------------------------------------------------------
[GRAPHIC] [TIFF OMITTED] TR10AU94.006
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Appendix C to Sec. 1910.1001 [Reserved]
Appendix D to Sec. 1910.1001--Medical Questionnaires; Mandatory
This mandatory appendix contains the medical questionnaires that
must be administered to all employees who are exposed to asbestos above
the permissible exposure limit, and who will therefore be included in
their employer's medical surveillance program. Part 1 of the appendix
contains the Initial Medical Questionnaire, which must be obtained for
all new hires who will be covered by the medical surveillance
requirements. Part 2 includes the abbreviated Periodical Medical
Questionnaire, which must be administered to all employees who are
provided periodic medical examinations under the medical surveillance
provisions of the standard.
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Appendix E to Sec. 1910.1001--Interpretation and Classification of Chest
Roentgenograms--Mandatory
(a) Chest roentgenograms shall be interpreted and classified in
accordance with a professionally accepted Classification system and
recorded on an interpretation form following the format of the CDC/NIOSH
(M) 2.8 form. As a minimum, the content within the bold lines of this
form (items 1 though 4) shall be included. This form is not to be
submitted to NIOSH.
(b) Roentgenograms shall be interpreted and classified only by a B-
reader, a board eligible/certified radiologist, or an experienced
physician with known expertise in pneumoconioses.
(c) All interpreters, whenever interpreting chest roentgenograms
made under this section, shall have immediately available for reference
a complete set of the ILO-U/C International Classification of
Radiographs for Pneumoconioses, 1980.
Appendix F to Sec. 1910.1001--Work Practices and Engineering Controls
for Automotive Brake and Clutch Inspection, Disassembly, Repair and
Assembly--Mandatory
This mandatory appendix specifies engineering controls and work
practices that must be implemented by the employer during automotive
brake and clutch inspection, disassembly, repair, and assembly
operations. Proper use of these engineering controls and work practices
by trained employees will reduce employees' asbestos exposure below the
permissible exposure level during clutch and brake inspection,
disassembly, repair, and assembly operations. The employer shall
institute engineering controls and work practices using either the
method set forth in paragraph [A] or paragraph [B] of this appendix, or
any other method which the employer can demonstrate to be equivalent in
terms of reducing employee exposure to asbestos as defined and which
meets the
[[Page 55]]
requirements described in paragraph [C] of this appendix, for those
facilities in which no more than 5 pairs of brakes or 5 clutches are
inspected, disassembled, reassembled and/or repaired per week, the
method set forth in paragraph [D] of this appendix may be used:
[A] Negative Pressure Enclosure/HEPA Vacuum System Method
(1) The brake and clutch inspection, disassembly, repair, and
assembly operations shall be enclosed to cover and contain the clutch or
brake assembly and to prevent the release of asbestos fibers into the
worker's breathing zone.
(2) The enclosure shall be sealed tightly and thoroughly inspected
for leaks before work begins on brake and clutch inspection,
disassembly, repair, and assembly.
(3) The enclosure shall be such that the worker can clearly see the
operation and shall provide impermeable sleeves through which the worker
can handle the brake and clutch inspection, disassembly, repair and
assembly. The integrity of the sleeves and ports shall be examined
before work begins.
(4) A HEPA-filtered vacuum shall be employed to maintain the
enclosure under negative pressure throughout the operation. Compressed-
air may be used to remove asbestos fibers or particles from the
enclosure.
(5) The HEPA vacuum shall be used first to loosen the asbestos
containing residue from the brake and clutch parts and then to evacuate
the loosened asbestos containing material from the enclosure and capture
the material in the vacuum filter.
(6) The vacuum's filter, when full, shall be first wetted with a
fine mist of water, then removed and placed immediately in an
impermeable container, labeled according to paragraph (j)(4) of this
section and disposed of according to paragraph (k) of this section.
(7) Any spills or releases of asbestos containing waste material
from inside of the enclosure or vacuum hose or vacuum filter shall be
immediately cleaned up and disposed of according to paragraph (k) of
this section.
[B] Low Pressure/Wet Cleaning Method
(1) A catch basin shall be placed under the brake assembly,
positioned to avoid splashes and spills.
(2) The reservoir shall contain water containing an organic solvent
or wetting agent. The flow of liquid shall be controlled such that the
brake assembly is gently flooded to prevent the asbestos-containing
brake dust from becoming airborne.
(3) The aqueous solution shall be allowed to flow between the brake
drum and brake support before the drum is removed.
(4) After removing the brake drum, the wheel hub and back of the
brake assembly shall be thoroughly wetted to suppress dust.
(5) The brake support plate, brake shoes and brake components used
to attach the brake shoes shall be thoroughly washed before removing the
old shoes.
(6) In systems using filters, the filters, when full, shall be first
wetted with a fine mist of water, then removed and placed immediately in
an impermeable container, labeled according to paragraph (j)(4) of this
section and disposed of according to paragraph (k) of this section.
(7) Any spills of asbestos-containing aqueous solution or any
asbestos-containing waste material shall be cleaned up immediately and
disposed of according to paragraph (k) of this section.
(8) The use of dry brushing during low pressure/wet cleaning
operations is prohibited.
[C] Equivalent Methods
An equivalent method is one which has sufficient written detail so
that it can be reproduced and has been demonstrated that the exposures
resulting from the equivalent method are equal to or less than the
exposures which would result from the use of the method described in
paragraph [A] of this appendix. For purposes of making this comparison,
the employer shall assume that exposures resulting from the use of the
method described in paragraph [A] of this appendix shall not exceed
0.016 f/cc, as measured by the OSHA reference method and as averaged
over at least 18 personal samples.
[D] Wet Method.
(1) A spray bottle, hose nozzle, or other implement capable of
delivering a fine mist of water or amended water or other delivery
system capable of delivering water at low pressure, shall be used to
first thoroughly wet the brake and clutch parts. Brake and clutch
components shall then be wiped clean with a cloth.
(2) The cloth shall be placed in an impermeable container, labelled
according to paragraph (j)(4) of this section and then disposed of
according to paragraph (k) of this section, or the cloth shall be
laundered in a way to prevent the release of asbestos fibers in excess
of 0.1 fiber per cubic centimeter of air.
(3) Any spills of solvent or any asbestos containing waste material
shall be cleaned up immediately according to paragraph (k) of this
section.
(4) The use of dry brushing during the wet method operations is
prohibited.
Appendix G to Sec. 1910.1001--Substance Technical Information for
Asbestos--Non-Mandatory
I. Substance Identification
A. Substance: ``Asbestos'' is the name of a class of magnesium-
silicate minerals that
[[Page 56]]
occur in fibrous form. Minerals that are included in this group are
chrysotile, crocidolite, amosite, tremolite asbestos, anthophyllite
asbestos, and actinolite asbestos.
B. Asbestos is used in the manufacture of heat-resistant clothing,
automative brake and clutch linings, and a variety of building materials
including floor tiles, roofing felts, ceiling tiles, asbestos-cement
pipe and sheet, and fire-resistant drywall. Asbestos is also present in
pipe and boiler insulation materials, and in sprayed-on materials
located on beams, in crawlspaces, and between walls.
C. The potential for a product containing asbestos to release
breatheable fibers depends on its degree of friability. Friable means
that the material can be crumbled with hand pressure and is therefore
likely to emit fibers. The fibrous or fluffy sprayed-on materials used
for fireproofing, insulation, or sound proofing are considered to be
friable, and they readily release airborne fibers if disturbed.
Materials such as vinyl-asbestos floor tile or roofing felts are
considered nonfriable and generally do not emit airborne fibers unless
subjected to sanding or sawing operations. Asbestos-cement pipe or sheet
can emit airborne fibers if the materials are cut or sawed, or if they
are broken during demolition operations.
D. Permissible exposure: Exposure to airborne asbestos fibers may
not exceed 0.2 fibers per cubic centimeter of air (0.1 f/cc) averaged
over the 8-hour workday.
II. Health Hazard Data
A. Asbestos can cause disabling respiratory disease and various
types of cancers if the fibers are inhaled. Inhaling or ingesting fibers
from contaminated clothing or skin can also result in these diseases.
The symptoms of these diseases generally do not appear for 20 or more
years after initial exposure.
B. Exposure to asbestos has been shown to cause lung cancer,
mesothelioma, and cancer of the stomach and colon. Mesothelioma is a
rare cancer of the thin membrane lining of the chest and abdomen.
Symptoms of mesothelioma include shortness of breath, pain in the walls
of the chest, and/or abdominal pain.
III. Respirators and Protective Clothing
A. Respirators: You are required to wear a respirator when
performing tasks that result in asbestos exposure that exceeds the
permissible exposure limit (PEL) of 0.1 f/cc. These conditions can occur
while your employer is in the process of installing engineering controls
to reduce asbestos exposure, or where engineering controls are not
feasible to reduce asbestos exposure. Air-purifying respirators equipped
with a high-efficiency particulate air (HEPA) filter can be used where
airborne asbestos fiber concentrations do not exceed 2 f/cc; otherwise,
air-supplied, positive-pressure, full facepiece respirators must be
used. Disposable respirators or dust masks are not permitted to be used
for asbestos work. For effective protection, respirators must fit your
face and head snugly. Your employer is required to conduct fit tests
when you are first assigned a respirator and every 6 months thereafter.
Respirators should not be loosened or removed in work situations where
their use is required.
B. Protective clothing: You are required to wear protective clothing
in work areas where asbestos fiber concentrations exceed the permissible
exposure limit.
IV. Disposal Procedures and Cleanup
A. Wastes that are generated by processes where asbestos is present
include:
1. Empty asbestos shipping containers.
2. Process wastes such as cuttings, trimmings, or reject material.
3. Housekeeping waste from sweeping or vacuuming.
4. Asbestos fireproofing or insulating material that is removed from
buildings.
5. Building products that contain asbestos removed during building
renovation or demolition.
6. Contaminated disposable protective clothing.
B. Empty shipping bags can be flattened under exhaust hoods and
packed into airtight containers for disposal. Empty shipping drums are
difficult to clean and should be sealed.
C. Vacuum bags or disposable paper filters should not be cleaned,
but should be sprayed with a fine water mist and placed into a labeled
waste container.
D. Process waste and housekeeping waste should be wetted with water
or a mixture of water and surfactant prior to packaging in disposable
containers.
E. Material containing asbestos that is removed from buildings must
be disposed of in leak-tight 6-mil thick plastic bags, plastic-lined
cardboard containers, or plastic-lined metal containers. These wastes,
which are removed while wet, should be sealed in containers before they
dry out to minimize the release of asbestos fibers during handling.
V. Access to Information
A. Each year, your employer is required to inform you of the
information contained in this standard and appendices for asbestos. In
addition, your employer must instruct you in the proper work practices
for handling materials containing asbestos, and the correct use of
protective equipment.
B. Your employer is required to determine whether you are being
exposed to asbestos. You or your representative has the right to observe
employee measurements and to
[[Page 57]]
record the results obtained. Your employer is required to inform you of
your exposure, and, if you are exposed above the permissible limit, he
or she is required to inform you of the actions that are being taken to
reduce your exposure to within the permissible limit.
C. Your employer is required to keep records of your exposures and
medical examinations. These exposure records must be kept for at least
thirty (30) years. Medical records must be kept for the period of your
employment plus thirty (30) years.
D. Your employer is required to release your exposure and medical
records to your physician or designated representative upon your written
request.
Appendix H to Sec. 1910.1001--Medical Surveillance Guidelines for
Asbestos Non-Mandatory
I. Route of Entry Inhalation, Ingestion
II. Toxicology
Clinical evidence of the adverse effects associated with exposure to
asbestos is present in the form of several well-conducted
epidemiological studies of occupationally exposed workers, family
contacts of workers, and persons living near asbestos mines. These
studies have shown a definite association between exposure to asbestos
and an increased incidence of lung cancer, pleural and peritoneal
mesothelioma, gastrointestinal cancer, and asbestosis. The latter is a
disabling fibrotic lung disease that is caused only by exposure to
asbestos. Exposure to asbestos has also been associated with an
increased incidence of esophageal, kidney, laryngeal, pharyngeal, and
buccal cavity cancers. As with other known chronic occupational
diseases, disease associated with asbestos generally appears about 20
years following the first occurrence of exposure: There are no known
acute effects associated with exposure to asbestos.
Epidemiological studies indicate that the risk of lung cancer among
exposed workers who smoke cigarettes is greatly increased over the risk
of lung cancer among non-exposed smokers or exposed nonsmokers. These
studies suggest that cessation of smoking will reduce the risk of lung
cancer for a person exposed to asbestos but will not reduce it to the
same level of risk as that existing for an exposed worker who has never
smoked.
III. Signs and Symptoms of Exposure-Related Disease
The signs and symptoms of lung cancer or gastrointestinal cancer
induced by exposure to asbestos are not unique, except that a chest X-
ray of an exposed patient with lung cancer may show pleural plaques,
pleural calcification, or pleural fibrosis. Symptoms characteristic of
mesothelioma include shortness of breath, pain in the walls of the
chest, or abdominal pain. Mesothelioma has a much longer latency period
compared with lung cancer (40 years versus 15-20 years), and
mesothelioma is therefore more likely to be found among workers who were
first exposed to asbestos at an early age. Mesothelioma is always fatal.
Asbestosis is pulmonary fibrosis caused by the accumulation of
asbestos fibers in the lungs. Symptoms include shortness of breath,
coughing, fatigue, and vague feelings of sickness. When the fibrosis
worsens, shortness of breath occurs even at rest. The diagnosis of
asbestosis is based on a history of exposure to asbestos, the presence
of characteristic radiologic changes, end-inspiratory crackles (rales),
and other clinical features of fibrosing lung disease. Pleural plaques
and thickening are observed on X-rays taken during the early stages of
the disease. Asbestosis is often a progressive disease even in the
absence of continued exposure, although this appears to be a highly
individualized characteristic. In severe cases, death may be caused by
respiratory or cardiac failure.
IV. Surveillance and Preventive Considerations
As noted above, exposure to asbestos has been linked to an increased
risk of lung cancer, mesothelioma, gastrointestinal cancer, and
asbestosis among occupationally exposed workers. Adequate screening
tests to determine an employee's potential for developing serious
chronic diseases, such as cancer, from exposure to asbestos do not
presently exist. However, some tests, particularly chest X-rays and
pulmonary function tests, may indicate that an employee has been
overexposed to asbestos increasing his or her risk of developing
exposure-related chronic diseases. It is important for the physician to
become familiar with the operating conditions in which occupational
exposure to asbestos is likely to occur. This is particularly important
in evaluating medical and work histories and in conducting physical
examinations. When an active employee has been identified as having been
overexposed to asbestos, measures taken by the employer to eliminate or
mitigate further exposure should also lower the risk of serious long-
term consequences.
The employer is required to institute a medical surveillance program
for all employees who are or will be exposed to asbestos at or above the
permissible exposure limit (0.1 fiber per cubic centimeter of air). All
examinations and procedures must be performed by or under the
supervision of a licensed physician, at a reasonable time and place, and
at no cost to the employee.
Although broad latitude is given to the physician in prescribing
specific tests to be
[[Page 58]]
included in the medical surveillance program, OSHA requires inclusion of
the following elements in the routine examination:
(i) Medical and work histories with special emphasis directed to
symptoms of the respiratory system, cardiovascular system, and digestive
tract.
(ii) Completion of the respiratory disease questionnaire contained
in Appendix D.
(iii) A physical examination including a chest roentgenogram and
pulmonary function test that includes measurement of the employee's
forced vital capacity (FVC) and forced expiratory volume at one second
(FEV1).
(iv) Any laboratory or other test that the examining physician deems
by sound medical practice to be necessary.
The employer is required to make the prescribed tests available at
least annually to those employees covered; more often than specified if
recommended by the examining physician; and upon termination of
employment.
The employer is required to provide the physician with the following
information: A copy of this standard and appendices; a description of
the mployee's duties as they relate to asbestos exposure; the employee's
representative level of exposure to asbestos; a description of any
personal protective and respiratory equipment used; and information from
previous medical examinations of the affected employee that is not
otherwise available to the physician. Making this information available
to the physician will aid in the evaluation of the employee's health in
relation to assigned duties and fitness to wear personal protective
equipment, if required.
The employer is required to obtain a written opinion from the
examining physician containing the results of the medical examination;
the physician's opinion as to whether the employee has any detected
medical conditions that would place the employee at an increased risk of
exposure-related disease; any recommended limitations on the employee or
on the use of personal protective equipment; and a statement that the
employee has been informed by the physician of the results of the
medical examination and of any medical conditions related to asbestos
exposure that require further explanation or treatment. This written
opinion must not reveal specific findings or diagnoses unrelated to
exposure to asbestos, and a copy of the opinion must be provided to the
affected employee.
Appendix I to Sec. 1910.1001--Smoking Cessation Program Information For
Asbestos--Non-Mandatory
The following organizations provide smoking cessation information
and program material.
1. The National Cancer Institute operates a toll-free Cancer
Information Service (CIS) with trained personnel to help you. Call 1-
800-4-CANCER* to reach the CIS office serving your area, or write:
Office of Cancer Communications, National Cancer Institute, National
Institutes of Health, Building 31, Room 10A24, Bethesda, Maryland 20892.
2. American Cancer Society, 3340 Peachtree Road, NE., Atlanta,
Georgia 30062, (404) 320-3333.
The American Cancer Society (ACS) is a voluntary organization
composed of 58 divisions and 3,100 local units. Through ``The Great
American Smokeout'' in November, the annual Cancer Crusade in April, and
numerous educational materials, ACS helps people learn about the health
hazards of smoking and become successful ex-smokers.
3. American Heart Association, 7320 Greenville Avenue, Dallas, Texas
75231, (214) 750-5300.
The American Heart Association (AHA) is a voluntary organization
with 130,000 members (physicians, scientists, and laypersons) in 55
state and regional groups. AHA produces a variety of publications and
audiovisual materials about the effects of smoking on the heart. AHA
also has developed a guidebook for incorporating a weight-control
component into smoking cessation programs.
4. American Lung Association, 1740 Broadway, New York, New York
10019, (212) 245-8000.
A voluntary organization of 7,500 members (physicians, nurses, and
laypersons), the American Lung Association (ALA) conducts numerous
public information programs about the health effect of smoking. ALA has
59 state and 85 local units. The organization actively supports
legislation and information campaigns for non-smokers' rights and
provides help for smokers who want to quit, for example, through
``Freedom From Smoking,'' a self-help smoking cessation program.
5. Office on Smoking and Health, U.S. Department of Health and,
Human Services, 5600 Fishers Lane, Park Building, Room 110, Rockville,
Maryland 20857.
The Office on Smoking and Health (OSH) is the Department of Health
and Human Services' lead agency in smoking control. OSH has sponsored
distribution of publications on smoking-realted topics, such as free
flyers on relapse after initial quitting, helping a friend or family
member quit smoking, the health hazards of smoking, and the effects of
parental smoking on teenagers.
*In Hawaii, on Oahu call 524-1234 (call collect from neighboring
islands),
Spanish-speaking staff members are available during daytime hours to
callers from the following areas: California, Florida, Georgia,
Illinois, New Jersey (area code 210), New York, and Texas. Consult your
local
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telephone directory for listings of local chapters.
Appendix J to Sec. 1910.1001--Polarized Light Microscopy of Asbestos--
Non-Mandatory
Method number: ID-191
Matrix: Bulk
Collection Procedure
Collect approximately 1 to 2 grams of each type of material and
place into separate 20 mL scintillation vials.
Analytical Procedure
A portion of each separate phase is analyzed by gross examination,
phase-polar examination, and central stop dispersion microscopy.
Commercial manufacturers and products mentioned in this method are
for descriptive use only and do not constitute endorsements by USDOL-
OSHA. Similar products from other sources may be substituted.
1. Introduction
This method describes the collection and analysis of asbestos bulk
materials by light microscopy techniques including phase- polar
illumination and central-stop dispersion microscopy. Some terms unique
to asbestos analysis are defined below:
Amphibole: A family of minerals whose crystals are formed by long,
thin units which have two thin ribbons of double chain silicate with a
brucite ribbon in between. The shape of each unit is similar to an ``I
beam''. Minerals important in asbestos analysis include cummingtonite-
grunerite, crocidolite, tremolite-actinolite and anthophyllite.
Asbestos: A term for naturally occurring fibrous minerals. Asbestos
includes chrysotile, cummingtonite-grunerite asbestos (amosite),
anthophyllite asbestos, tremolite asbestos, crocidolite, actinolite
asbestos and any of these minerals which have been chemically treated or
altered. The precise chemical formulation of each species varies with
the location from which it was mined. Nominal compositions are listed:
Chrysotile...............................Mg3 Si2
O5(OH)4
Crocidolite (Riebeckite asbestos)....Na2
Fe32+ Fe23+
Si8 O22(OH)2
Cummingtonite-Grunerite asbestos (Amosite)..........(Mg,Fe)7
Si8 O22(OH)2
Tremolite-Actinolite asbestos................Ca2
(Mg,Fe)5 Si8
O22(OH)2
Anthophyllite asbestos.............(Mg,Fe)7 Si8
O22(OH)2
Asbestos Fiber: A fiber of asbestos meeting the criteria for a
fiber. (See section 3.5.)
Aspect Ratio: The ratio of the length of a fiber to its diameter
usually defined as ``length : width'', e.g. 3:1.
Brucite: A sheet mineral with the composition Mg(OH)2.
Central Stop Dispersion Staining (microscope): This is a dark field
microscope technique that images particles using only light refracted by
the particle, excluding light that travels through the particle
unrefracted. This is usually accomplished with a McCrone objective or
other arrangement which places a circular stop with apparent aperture
equal to the objective aperture in the back focal plane of the
microscope.
Cleavage Fragments: Mineral particles formed by the comminution of
minerals, especially those characterized by relatively parallel sides
and moderate aspect ratio.
Differential Counting: The term applied to the practice of excluding
certain kinds of fibers from a phase contrast asbestos count because
they are not asbestos.
Fiber: A particle longer than or equal to 5 m with a
length to width ratio greater than or equal to 3:1. This may include
cleavage fragments. (see section 3.5 of this appendix).
Phase Contrast: Contrast obtained in the microscope by causing light
scattered by small particles to destructively interfere with unscattered
light, thereby enhancing the visibility of very small particles and
particles with very low intrinsic contrast.
Phase Contrast Microscope: A microscope configured with a phase mask
pair to create phase contrast. The technique which uses this is called
Phase Contrast Microscopy (PCM).
Phase-Polar Analysis: This is the use of polarized light in a phase
contrast microscope. It is used to see the same size fibers that are
visible in air filter analysis. Although fibers finer than 1 m
are visible, analysis of these is inferred from analysis of larger
bundles that are usually present.
Phase-Polar Microscope: The phase-polar microscope is a phase
contrast microscope which has an analyzer, a polarizer, a first order
red plate and a rotating phase condenser all in place so that the
polarized light image is enhanced by phase contrast.
Sealing Encapsulant: This is a product which can be applied,
preferably by spraying, onto an asbestos surface which will seal the
surface so that fibers cannot be released.
Serpentine: A mineral family consisting of minerals with the general
composition Mg3(Si2O5(OH)4 having the
magnesium in brucite layer over a silicate layer. Minerals important in
asbestos analysis included in this family are chrysotile, lizardite,
antigorite.
1.1. History
Light microscopy has been used for well over 100 years for the
determination of mineral species. This analysis is carried out using
specialized polarizing microscopes as
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well as bright field microscopes. The identification of minerals is an
on-going process with many new minerals described each year. The first
recorded use of asbestos was in Finland about 2500 B.C. where the
material was used in the mud wattle for the wooden huts the people lived
in as well as strengthening for pottery. Adverse health aspects of the
mineral were noted nearly 2000 years ago when Pliny the Younger wrote
about the poor health of slaves in the asbestos mines. Although known to
be injurious for centuries, the first modern references to its toxicity
were by the British Labor Inspectorate when it banned asbestos dust from
the workplace in 1898. Asbestosis cases were described in the literature
after the turn of the century. Cancer was first suspected in the mid
1930's and a causal link to mesothelioma was made in 1965. Because of
the public concern for worker and public safety with the use of this
material, several different types of analysis were applied to the
determination of asbestos content. Light microscopy requires a great
deal of experience and craft. Attempts were made to apply less
subjective methods to the analysis. X-ray diffraction was partially
successful in determining the mineral types but was unable to separate
out the fibrous portions from the non-fibrous portions. Also, the
minimum detection limit for asbestos analysis by X-ray diffraction (XRD)
is about 1%. Differential Thermal Analysis (DTA) was no more successful.
These provide useful corroborating information when the presence of
asbestos has been shown by microscopy; however, neither can determine
the difference between fibrous and non-fibrous minerals when both habits
are present. The same is true of Infrared Absorption (IR).
When electron microscopy was applied to asbestos analysis, hundreds
of fibers were discovered present too small to be visible in any light
microscope. There are two different types of electron microscope used
for asbestos analysis: Scanning Electron Microscope (SEM) and
Transmission Electron Microscope (TEM). Scanning Electron Microscopy is
useful in identifying minerals. The SEM can provide two of the three
pieces of information required to identify fibers by electron
microscopy: morphology and chemistry. The third is structure as
determined by Selected Area Electron Diffraction--SAED which is
performed in the TEM. Although the resolution of the SEM is sufficient
for very fine fibers to be seen, accuracy of chemical analysis that can
be performed on the fibers varies with fiber diameter in fibers of less
than 0.2 m diameter. The TEM is a powerful tool to identify
fibers too small to be resolved by light microscopy and should be used
in conjunction with this method when necessary. The TEM can provide all
three pieces of information required for fiber identification. Most
fibers thicker than 1 m can adequately be defined in the light
microscope. The light microscope remains as the best instrument for the
determination of mineral type. This is because the minerals under
investigation were first described analytically with the light
microscope. It is inexpensive and gives positive identification for most
samples analyzed. Further, when optical techniques are inadequate, there
is ample indication that alternative techniques should be used for
complete identification of the sample.
1.2. Principle
Minerals consist of atoms that may be arranged in random order or in
a regular arrangement. Amorphous materials have atoms in random order
while crystalline materials have long range order. Many materials are
transparent to light, at least for small particles or for thin sections.
The properties of these materials can be investigated by the effect that
the material has on light passing through it. The six asbestos minerals
are all crystalline with particular properties that have been identified
and cataloged. These six minerals are anisotropic. They have a regular
array of atoms, but the arrangement is not the same in all directions.
Each major direction of the crystal presents a different regularity.
Light photons travelling in each of these main directions will encounter
different electrical neighborhoods, affecting the path and time of
travel. The techniques outlined in this method use the fact that light
traveling through fibers or crystals in different directions will behave
differently, but predictably. The behavior of the light as it travels
through a crystal can be measured and compared with known or determined
values to identify the mineral species. Usually, Polarized Light
Microscopy (PLM) is performed with strain-free objectives on a bright-
field microscope platform. This would limit the resolution of the
microscope to about 0.4 m. Because OSHA requires the counting
and identification of fibers visible in phase contrast, the phase
contrast platform is used to visualize the fibers with the polarizing
elements added into the light path. Polarized light methods cannot
identify fibers finer than about 1 m in diameter even though
they are visible. The finest fibers are usually identified by inference
from the presence of larger, identifiable fiber bundles. When fibers are
present, but not identifiable by light microscopy, use either SEM or TEM
to determine the fiber identity.
1.3. Advantages and Disadvantages
The advantages of light microcopy are:
(a) Basic identification of the materials was first performed by
light microscopy and gross analysis. This provides a large base of
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published information against which to check analysis and analytical
technique.
(b) The analysis is specific to fibers. The minerals present can
exist in asbestiform, fibrous, prismatic, or massive varieties all at
the same time. Therefore, bulk methods of analysis such as X-ray
diffraction, IR analysis, DTA, etc. are inappropriate where the material
is not known to be fibrous.
(c) The analysis is quick, requires little preparation time, and can
be performed on-site if a suitably equipped microscope is available.
The disadvantages are:
(a) Even using phase-polar illumination, not all the fibers present
may be seen. This is a problem for very low asbestos concentrations
where agglomerations or large bundles of fibers may not be present to
allow identification by inference.
(b) The method requires a great degree of sophistication on the part
of the microscopist. An analyst is only as useful as his mental catalog
of images. Therefore, a microscopist's accuracy is enhanced by
experience. The mineralogical training of the analyst is very important.
It is the basis on which subjective decisions are made.
(c) The method uses only a tiny amount of material for analysis.
This may lead to sampling bias and false results (high or low). This is
especially true if the sample is severely inhomogeneous.
(d) Fibers may be bound in a matrix and not distinguishable as
fibers so identification cannot be made.
1.4. Method Performance
1.4.1. This method can be used for determination of asbestos content
from 0 to 100% asbestos. The detection limit has not been adequately
determined, although for selected samples, the limit is very low,
depending on the number of particles examined. For mostly homogeneous,
finely divided samples, with no difficult fibrous interferences, the
detection limit is below 1%. For inhomogeneous samples (most samples),
the detection limit remains undefined. NIST has conducted proficiency
testing of laboratories on a national scale. Although each round is
reported statistically with an average, control limits, etc., the
results indicate a difficulty in establishing precision especially in
the low concentration range. It is suspected that there is significant
bias in the low range especially near 1%. EPA tried to remedy this by
requiring a mandatory point counting scheme for samples less than 10%.
The point counting procedure is tedious, and may introduce significant
biases of its own. It has not been incorporated into this method.
1.4.2. The precision and accuracy of the quantitation tests
performed in this method are unknown. Concentrations are easier to
determine in commercial products where asbestos was deliberately added
because the amount is usually more than a few percent. An analyst's
results can be ``calibrated'' against the known amounts added by the
manufacturer. For geological samples, the degree of homogeneity affects
the precision.
1.4.3. The performance of the method is analyst dependent. The
analyst must choose carefully and not necessarily randomly the portions
for analysis to assure that detection of asbestos occurs when it is
present. For this reason, the analyst must have adequate training in
sample preparation, and experience in the location and identification of
asbestos in samples. This is usually accomplished through substantial
on-the-job training as well as formal education in mineralogy and
microscopy.
1.5. Interferences
Any material which is long, thin, and small enough to be viewed
under the microscope can be considered an interference for asbestos.
There are literally hundreds of interferences in workplaces. The
techniques described in this method are normally sufficient to eliminate
the interferences. An analyst's success in eliminating the interferences
depends on proper training.
Asbestos minerals belong to two mineral families: the serpentines
and the amphiboles. In the serpentine family, the only common fibrous
mineral is chrysotile. Occasionally, the mineral antigorite occurs in a
fibril habit with morphology similar to the amphiboles. The amphibole
minerals consist of a score of different minerals of which only five are
regulated by federal standard: amosite, crocidolite, anthophyllite
asbestos, tremolite asbestos and actinolite asbestos. These are the only
amphibole minerals that have been commercially exploited for their
fibrous properties; however, the rest can and do occur occasionally in
asbestiform habit.
In addition to the related mineral interferences, other minerals
common in building material may present a problem for some
microscopists: gypsum, anhydrite, brucite, quartz fibers, talc fibers or
ribbons, wollastonite, perlite, attapulgite, etc. Other fibrous
materials commonly present in workplaces are: fiberglass, mineral wool,
ceramic wool, refractory ceramic fibers, kevlar, nomex, synthetic
fibers, graphite or carbon fibers, cellulose (paper or wood) fibers,
metal fibers, etc.
Matrix embedding material can sometimes be a negative interference.
The analyst may not be able to easily extract the fibers from the matrix
in order to use the method. Where possible, remove the matrix before the
analysis, taking careful note of the loss of weight. Some common matrix
materials are: vinyl, rubber, tar, paint, plant fiber, cement, and
epoxy. A further negative interference is that the asbestos fibers
themselves may be either too small to be seen in Phase contrast
Microscopy (PCM) or of a very low
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fibrous quality, having the appearance of plant fibers. The analyst's
ability to deal with these materials increases with experience.
1.6. Uses and Occupational Exposure
Asbestos is ubiquitous in the environment. More than 40% of the land
area of the United States is composed of minerals which may contain
asbestos. Fortunately, the actual formation of great amounts of asbestos
is relatively rare. Nonetheless, there are locations in which
environmental exposure can be severe such as in the Serpentine Hills of
California.
There are thousands of uses for asbestos in industry and the home.
Asbestos abatement workers are the most current segment of the
population to have occupational exposure to great amounts of asbestos.
If the material is undisturbed, there is no exposure. Exposure occurs
when the asbestos-containing material is abraded or otherwise disturbed
during maintenance operations or some other activity. Approximately 95%
of the asbestos in place in the United States is chrysotile.
Amosite and crocidolite make up nearly all the difference. Tremolite
and anthophyllite make up a very small percentage. Tremolite is found in
extremely small amounts in certain chrysotile deposits. Actinolite
exposure is probably greatest from environmental sources, but has been
identified in vermiculite containing, sprayed-on insulating materials
which may have been certified as asbestos-free.
1.7. Physical and Chemical Properties
The nominal chemical compositions for the asbestos minerals were
given in Section 1. Compared to cleavage fragments of the same minerals,
asbestiform fibers possess a high tensile strength along the fiber axis.
They are chemically inert, non- combustible, and heat resistant. Except
for chrysotile, they are insoluble in Hydrochloric acid (HCl).
Chrysotile is slightly soluble in HCl. Asbestos has high electrical
resistance and good sound absorbing characteristics. It can be woven
into cables, fabrics or other textiles, or matted into papers, felts,
and mats.
1.8. Toxicology (This Section is for Information Only and Should Not Be
Taken as OSHA Policy)
Possible physiologic results of respiratory exposure to asbestos are
mesothelioma of the pleura or peritoneum, interstitial fibrosis,
asbestosis, pneumoconiosis, or respiratory cancer. The possible
consequences of asbestos exposure are detailed in the NIOSH Criteria
Document or in the OSHA Asbestos Standards 29 CFR 1910.1001 and 29 CFR
1926.1101 and 29 CFR 1915.1001.
2. Sampling Procedure
2.1. Equipment for Sampling
(a) Tube or cork borer sampling device
(b) Knife
(c) 20 mL scintillation vial or similar vial
(d) Sealing encapsulant
2.2. Safety Precautions
Asbestos is a known carcinogen. Take care when sampling. While in an
asbestos-containing atmosphere, a properly selected and fit-tested
respirator should be worn. Take samples in a manner to cause the least
amount of dust. Follow these general guidelines:
(a) Do not make unnecessary dust.
(b) Take only a small amount (1 to 2 g).
(c) Tightly close the sample container.
(d) Use encapsulant to seal the spot where the sample was taken, if
necessary.
2.3. Sampling Procedure
Samples of any suspect material should be taken from an
inconspicuous place. Where the material is to remain, seal the sampling
wound with an encapsulant to eliminate the potential for exposure from
the sample site. Microscopy requires only a few milligrams of material.
The amount that will fill a 20 mL scintillation vial is more than
adequate. Be sure to collect samples from all layers and phases of
material. If possible, make separate samples of each different phase of
the material. This will aid in determining the actual hazard. DO NOT USE
ENVELOPES, PLASTIC OR PAPER BAGS OF ANY KIND TO COLLECT SAMPLES. The use
of plastic bags presents a contamination hazard to laboratory personnel
and to other samples. When these containers are opened, a bellows effect
blows fibers out of the container onto everything, including the person
opening the container.
If a cork-borer type sampler is available, push the tube through the
material all the way, so that all layers of material are sampled. Some
samplers are intended to be disposable. These should be capped and sent
to the laboratory. If a non-disposable cork borer is used, empty the
contents into a scintillation vial and send to the laboratory.
Vigorously and completely clean the cork borer between samples.
2.4 Shipment
Samples packed in glass vials must not touch or they might break in
shipment.
(a) Seal the samples with a sample seal over the end to guard
against tampering and to identify the sample.
(b) Package the bulk samples in separate packages from the air
samples. They may cross-contaminate each other and will invalidate the
results of the air samples.
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(c) Include identifying paperwork with the samples, but not in
contact with the suspected asbestos.
(d) To maintain sample accountability, ship the samples by certified
mail, overnight express, or hand carry them to the laboratory.
3. Analysis
The analysis of asbestos samples can be divided into two major
parts: sample preparation and microscopy. Because of the different
asbestos uses that may be encountered by the analyst, each sample may
need different preparation steps. The choices are outlined below. There
are several different tests that are performed to identify the asbestos
species and determine the percentage. They will be explained below.
3.1. Safety
(a) Do not create unnecessary dust. Handle the samples in HEPA-
filter equipped hoods. If samples are received in bags, envelopes or
other inappropriate container, open them only in a hood having a face
velocity at or greater than 100 fpm. Transfer a small amount to a
scintillation vial and only handle the smaller amount.
(b) Open samples in a hood, never in the open lab area.
(c) Index of refraction oils can be toxic. Take care not to get this
material on the skin. Wash immediately with soap and water if this
happens.
(d) Samples that have been heated in the muffle furnace or the
drying oven may be hot. Handle them with tongs until they are cool
enough to handle.
(e) Some of the solvents used, such as THF (tetrahydrofuran), are
toxic and should only be handled in an appropriate fume hood and
according to instructions given in the Material Safety Data Sheet
(MSDS).
3.2. Equipment
(a) Phase contrast microscope with 10x, 16x and 40x objectives, 10x
wide-field eyepieces, G-22 Walton-Beckett graticule, Whipple disk,
polarizer, analyzer and first order red or gypsum plate, 100 Watt
illuminator, rotating position condenser with oversize phase rings,
central stop dispersion objective, Kohler illumination and a rotating
mechanical stage.
(b) Stereo microscope with reflected light illumination, transmitted
light illumination, polarizer, analyzer and first order red or gypsum
plate, and rotating stage.
(c) Negative pressure hood for the stereo microscope
(d) Muffle furnace capable of 600 deg.C
(e) Drying oven capable of 50--150 deg.C
(f) Aluminum specimen pans
(g) Tongs for handling samples in the furnace
(h) High dispersion index of refraction oils (Special for dispersion
staining.)
n = 1.550
n = 1.585
n = 1.590
n = 1.605
n = 1.620
n = 1.670
n = 1.680
n = 1.690
(i) A set of index of refraction oils from about n=1.350 to n=2.000
in n=0.005 increments. (Standard for Becke line analysis.)
(j) Glass slides with painted or frosted ends 1 x 3 inches 1mm
thick, precleaned.
(k) Cover Slips 22 x 22 mm, #1\1/2\
(l) Paper clips or dissection needles
(m) Hand grinder
(n) Scalpel with both #10 and #11 blades
(o) 0.1 molar HCl
(p) Decalcifying solution (Baxter Scientific Products)
Ethylenediaminetetraacetic Acid,
Tetrasodium......................................................0.7 g/l
Sodium Potassium Tartrate...................................8.0 mg/liter
Hydrochloric Acid...........................................99.2 g/liter
Sodium Tartrate.............................................0.14 g/liter
(q) Tetrahydrofuran (THF)
(r) Hotplate capable of 60 deg.C
(s) Balance
(t) Hacksaw blade
(u) Ruby mortar and pestle
3.3. Sample Pre-Preparation
Sample preparation begins with pre-preparation which may include
chemical reduction of the matrix, heating the sample to dryness or
heating in the muffle furnace. The end result is a sample which has been
reduced to a powder that is sufficiently fine to fit under the cover
slip. Analyze different phases of samples separately, e.g., tile and the
tile mastic should be analyzed separately as the mastic may contain
asbestos while the tile may not.
(a) Wet samples
Samples with a high water content will not give the proper
dispersion colors and must be dried prior to sample mounting. Remove the
lid of the scintillation vial, place the bottle in the drying oven and
heat at 100 deg.C to dryness (usually about 2 h). Samples which are not
submitted to the lab in glass must be removed and placed in glass vials
or aluminum weighing pans before placing them in the drying oven.
(b) Samples With Organic Interference--Muffle Furnace
These may include samples with tar as a matrix, vinyl asbestos tile,
or any other organic that can be reduced by heating. Remove the sample
from the vial and weigh in a balance to determine the weight of the
submitted portion. Place the sample in a muffle
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furnace at 500 deg.C for 1 to 2 h or until all obvious organic material
has been removed. Retrieve, cool and weigh again to determine the weight
loss on ignition. This is necessary to determine the asbestos content of
the submitted sample, because the analyst will be looking at a reduced
sample.
Note: Heating above 600 deg.C will cause the sample to undergo a
structural change which, given sufficient time, will convert the
chrysotile to forsterite. Heating even at lower temperatures for 1 to 2
h may have a measurable effect on the optical properties of the
minerals. If the analyst is unsure of what to expect, a sample of
standard asbestos should be heated to the same temperature for the same
length of time so that it can be examined for the proper interpretation.
(c) Samples With Organic Interference--THF
Vinyl asbestos tile is the most common material treated with this
solvent, although, substances containing tar will sometimes yield to
this treatment. Select a portion of the material and then grind it up if
possible. Weigh the sample and place it in a test tube. Add sufficient
THF to dissolve the organic matrix. This is usually about 4 to 5 mL.
Remember, THF is highly flammable. Filter the remaining material through
a tared silver membrane, dry and weigh to determine how much is left
after the solvent extraction. Further process the sample to remove
carbonate or mount directly.
(d) Samples With Carbonate Interference
Carbonate material is often found on fibers and sometimes must be
removed in order to perform dispersion microscopy. Weigh out a portion
of the material and place it in a test tube. Add a sufficient amount of
0.1 M HCl or decalcifying solution in the tube to react all the
carbonate as evidenced by gas formation; i.e., when the gas bubbles
stop, add a little more solution. If no more gas forms, the reaction is
complete. Filter the material out through a tared silver membrane, dry
and weigh to determine the weight lost.
3.4. Sample Preparation
Samples must be prepared so that accurate determination can be made
of the asbestos type and amount present. The following steps are carried
out in the low-flow hood (a low-flow hood has less than 50 fpm flow):
(1) If the sample has large lumps, is hard, or cannot be made to lie
under a cover slip, the grain size must be reduced. Place a small amount
between two slides and grind the material between them or grind a small
amount in a clean mortar and pestle. The choice of whether to use an
alumina, ruby, or diamond mortar depends on the hardness of the
material. Impact damage can alter the asbestos mineral if too much
mechanical shock occurs. (Freezer mills can completely destroy the
observable crystallinity of asbestos and should not be used). For some
samples, a portion of material can be shaved off with a scalpel, ground
off with a hand grinder or hack saw blade.
The preparation tools should either be disposable or cleaned
thoroughly. Use vigorous scrubbing to loosen the fibers during the
washing. Rinse the implements with copious amounts of water and air-dry
in a dust-free environment.
(2) If the sample is powder or has been reduced as in (1) above, it
is ready to mount. Place a glass slide on a piece of optical tissue and
write the identification on the painted or frosted end. Place two drops
of index of refraction medium n=1.550 on the slide. (The medium n=1.550
is chosen because it is the matching index for chrysotile. Dip the end
of a clean paper-clip or dissecting needle into the droplet of
refraction medium on the slide to moisten it. Then dip the probe into
the powder sample. Transfer what sticks on the probe to the slide. The
material on the end of the probe should have a diameter of about 3 mm
for a good mount. If the material is very fine, less sample may be
appropriate. For non-powder samples such as fiber mats, forceps should
be used to transfer a small amount of material to the slide. Stir the
material in the medium on the slide, spreading it out and making the
preparation as uniform as possible. Place a cover-slip on the
preparation by gently lowering onto the slide and allowing it to fall
``trapdoor'' fashion on the preparation to push out any bubbles. Press
gently on the cover slip to even out the distribution of particulate on
the slide. If there is insufficient mounting oil on the slide, one or
two drops may be placed near the edge of the coverslip on the slide.
Capillary action will draw the necessary amount of liquid into the
preparation. Remove excess oil with the point of a laboratory wiper.
Treat at least two different areas of each phase in this fashion.
Choose representative areas of the sample. It may be useful to select
particular areas or fibers for analysis. This is useful to identify
asbestos in severely inhomogeneous samples.
When it is determined that amphiboles may be present, repeat the
above process using the appropriate high-dispersion oils until an
identification is made or all six asbestos minerals have been ruled out.
Note that percent determination must be done in the index medium 1.550
because amphiboles tend to disappear in their matching mediums.
3.5. Analytical Procedure
Note: This method presumes some knowledge of mineralogy and optical
petrography.
The analysis consists of three parts: The determination of whether
there is asbestos
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present, what type is present and the determination of how much is
present. The general flow of the analysis is:
(1) Gross examination.
(2) Examination under polarized light on the stereo microscope.
(3) Examination by phase-polar illumination on the compound phase
microscope.
(4) Determination of species by dispersion stain. Examination by
Becke line analysis may also be used; however, this is usually more
cumbersome for asbestos determination.
(5) Difficult samples may need to be analyzed by SEM or TEM, or the
results from those techniques combined with light microscopy for a
definitive identification. Identification of a particle as asbestos
requires that it be asbestiform. Description of particles should follow
the suggestion of Campbell. (Figure 1)
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[GRAPHIC] [TIFF OMITTED] TR10AU94.007
For the purpose of regulation, the mineral must be one of the six
minerals covered and must be in the asbestos growth habit. Large
specimen samples of asbestos generally have the gross appearance of
wood. Fibers are easily parted from it. Asbestos fibers are very long
compared with their widths. The fibers have a very high tensile strength
as demonstrated by bending without breaking. Asbestos fibers exist in
bundles that are easily parted, show longitudinal fine structure and may
be tufted at the ends showing ``bundle of sticks'' morphology. In the
microscope
[[Page 67]]
some of these properties may not be observable. Amphiboles do not always
show striations along their length even when they are asbestos. Neither
will they always show tufting. They generally do not show a curved
nature except for very long fibers. Asbestos and asbestiform minerals
are usually characterized in groups by extremely high aspect ratios
(greater than 100:1). While aspect ratio analysis is useful for
characterizing populations of fibers, it cannot be used to identify
individual fibers of intermediate to short aspect ratio. Observation of
many fibers is often necessary to determine whether a sample consists of
``cleavage fragments'' or of asbestos fibers.
Most cleavage fragments of the asbestos minerals are easily
distinguishable from true asbestos fibers. This is because true cleavage
fragments usually have larger diameters than 1 m. Internal
structure of particles larger than this usually shows them to have no
internal fibrillar structure. In addition, cleavage fragments of the
monoclinic amphiboles show inclined extinction under crossed polars with
no compensator. Asbestos fibers usually show extinction at zero degrees
or ambiguous extinction if any at all. Morphologically, the larger
cleavage fragments are obvious by their blunt or stepped ends showing
prismatic habit. Also, they tend to be acicular rather than filiform.
Where the particles are less than 1 m in diameter and have
an aspect ratio greater than or equal to 3:1, it is recommended that the
sample be analyzed by SEM or TEM if there is any question whether the
fibers are cleavage fragments or asbestiform particles.
Care must be taken when analyzing by electron microscopy because the
interferences are different from those in light microscopy and may
structurally be very similar to asbestos. The classic interference is
between anthophyllite and biopyribole or intermediate fiber. Use the
same morphological clues for electron microscopy as are used for light
microscopy, e.g. fibril splitting, internal longitudinal striation,
fraying, curvature, etc.
(1) Gross examination:
Examine the sample, preferably in the glass vial. Determine the
presence of any obvious fibrous component. Estimate a percentage based
on previous experience and current observation. Determine whether any
pre- preparation is necessary. Determine the number of phases present.
This step may be carried out or augmented by observation at 6 to 40 x
under a stereo microscope.
(2) After performing any necessary pre-preparation, prepare slides
of each phase as described above. Two preparations of the same phase in
the same index medium can be made side-by-side on the same glass for
convenience. Examine with the polarizing stereo microscope. Estimate the
percentage of asbestos based on the amount of birefringent fiber
present.
(3) Examine the slides on the phase-polar microscopes at
magnifications of 160 and 400 x . Note the morphology of the fibers.
Long, thin, very straight fibers with little curvature are indicative of
fibers from the amphibole family. Curved, wavy fibers are usually
indicative of chrysotile. Estimate the percentage of asbestos on the
phase-polar microscope under conditions of crossed polars and a gypsum
plate. Fibers smaller than 1.0 m in thickness must be
identified by inference to the presence of larger, identifiable fibers
and morphology. If no larger fibers are visible, electron microscopy
should be performed. At this point, only a tentative identification can
be made. Full identification must be made with dispersion microscopy.
Details of the tests are included in the appendices.
(4) Once fibers have been determined to be present, they must be
identified. Adjust the microscope for dispersion mode and observe the
fibers. The microscope has a rotating stage, one polarizing element, and
a system for generating dark-field dispersion microscopy (see Section
4.6. of this appendix). Align a fiber with its length parallel to the
polarizer and note the color of the Becke lines. Rotate the stage to
bring the fiber length perpendicular to the polarizer and note the
color. Repeat this process for every fiber or fiber bundle examined. The
colors must be consistent with the colors generated by standard asbestos
reference materials for a positive identification. In n=1.550,
amphiboles will generally show a yellow to straw-yellow color indicating
that the fiber indices of refraction are higher than the liquid. If
long, thin fibers are noted and the colors are yellow, prepare further
slides as above in the suggested matching liquids listed below:
------------------------------------------------------------------------
Type of asbestos Index of refraction
------------------------------------------------------------------------
Chrysotile.......................... n=1.550.
Amosite............................. n=1.670 r 1.680.
Crocidolite......................... n=1.690.
Anthophyllite....................... n=1.605 nd 1.620.
Tremolite........................... n=1.605 and 1.620.
Actinolite.......................... n=1.620.
------------------------------------------------------------------------
Where more than one liquid is suggested, the first is preferred;
however, in some cases this liquid will not give good dispersion color.
Take care to avoid interferences in the other liquid; e.g., wollastonite
in n=1.620 will give the same colors as tremolite. In n=1.605
wollastonite will appear yellow in all directions. Wollastonite may be
determined under crossed polars as it will change from blue to yellow as
it is rotated along its fiber axis by tapping on the cover slip.
Asbestos minerals will not change in this way.
Determination of the angle of extinction may, when present, aid in
the determination
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of anthophyllite from tremolite. True asbestos fibers usually have
0 deg. extinction or ambiguous extinction, while cleavage fragments have
more definite extinction.
Continue analysis until both preparations have been examined and all
present species of asbestos are identified. If there are no fibers
present, or there is less than 0.1% present, end the analysis with the
minimum number of slides (2).
(5) Some fibers have a coating on them which makes dispersion
microscopy very difficult or impossible. Becke line analysis or electron
microscopy may be performed in those cases. Determine the percentage by
light microscopy. TEM analysis tends to overestimate the actual
percentage present.
(6) Percentage determination is an estimate of occluded area,
tempered by gross observation. Gross observation information is used to
make sure that the high magnification microscopy does not greatly over-
or under- estimate the amount of fiber present. This part of the
analysis requires a great deal of experience. Satisfactory models for
asbestos content analysis have not yet been developed, although some
models based on metallurgical grain-size determination have found some
utility. Estimation is more easily handled in situations where the grain
sizes visible at about 160 x are about the same and the sample is
relatively homogeneous.
View all of the area under the cover slip to make the percentage
determination. View the fields while moving the stage, paying attention
to the clumps of material. These are not usually the best areas to
perform dispersion microscopy because of the interference from other
materials. But, they are the areas most likely to represent the accurate
percentage in the sample. Small amounts of asbestos require slower
scanning and more frequent analysis of individual fields.
Report the area occluded by asbestos as the concentration. This
estimate does not generally take into consideration the difference in
density of the different species present in the sample. For most samples
this is adequate. Simulation studies with similar materials must be
carried out to apply microvisual estimation for that purpose and is
beyond the scope of this procedure.
(7) Where successive concentrations have been made by chemical or
physical means, the amount reported is the percentage of the material in
the ``as submitted'' or original state. The percentage determined by
microscopy is multiplied by the fractions remaining after pre-
preparation steps to give the percentage in the original sample. For
example:
Step 1. 60% remains after heating at 550 deg.C for 1 h. Step 2. 30%
of the residue of step 1 remains after dissolution of carbonate in 0.1 m
HCl.
Step 3. Microvisual estimation determines that 5% of the sample is
chrysotile asbestos.
The reported result is:
R=(Microvisual result in percent) x (Fraction remaining after step
2) x (Fraction remaining of original sample after step 1)
R=(5) x (.30) x (.60)=0.9%
(8) Report the percent and type of asbestos present. For samples
where asbestos was identified, but is less than 1.0%, report ``Asbestos
present, less than 1.0%.'' There must have been at least two observed
fibers or fiber bundles in the two preparations to be reported as
present. For samples where asbestos was not seen, report as ``None
Detected.''
4. Auxiliary Information
Because of the subjective nature of asbestos analysis, certain
concepts and procedures need to be discussed in more depth. This
information will help the analyst understand why some of the procedures
are carried out the way they are.
4.1. Light
Light is electromagnetic energy. It travels from its source in
packets called quanta. It is instructive to consider light as a plane
wave. The light has a direction of travel. Perpendicular to this and
mutually perpendicular to each other, are two vector components. One is
the magnetic vector and the other is the electric vector. We shall only
be concerned with the electric vector. In this description, the
interaction of the vector and the mineral will describe all the
observable phenomena. From a light source such a microscope illuminator,
light travels in all different direction from the filament.
In any given direction away from the filament, the electric vector
is perpendicular to the direction of travel of a light ray. While
perpendicular, its orientation is random about the travel axis. If the
electric vectors from all the light rays were lined up by passing the
light through a filter that would only let light rays with electric
vectors oriented in one direction pass, the light would then be
POLARIZED.
Polarized light interacts with matter in the direction of the
electric vector. This is the polarization direction. Using this property
it is possible to use polarized light to probe different materials and
identify them by how they interact with light.
The speed of light in a vacuum is a constant at about 2.99 x 10 \8\
m/s. When light travels in different materials such as air, water,
minerals or oil, it does not travel at this speed. It travels slower.
This slowing is a function of both the material through which the light
is traveling and the wavelength or
[[Page 69]]
frequency of the light. In general, the more dense the material, the
slower the light travels. Also, generally, the higher the frequency, the
slower the light will travel. The ratio of the speed of light in a
vacuum to that in a material is called the index of refraction (n). It
is usually measured at 589 nm (the sodium D line). If white light (light
containing all the visible wavelengths) travels through a material, rays
of longer wavelengths will travel faster than those of shorter
wavelengths, this separation is called dispersion. Dispersion is used as
an identifier of materials as described in Section 4.6.
4.2. Material Properties
Materials are either amorphous or crystalline. The difference
between these two descriptions depends on the positions of the atoms in
them. The atoms in amorphous materials are randomly arranged with no
long range order. An example of an amorphous material is glass. The
atoms in crystalline materials, on the other hand, are in regular arrays
and have long range order. Most of the atoms can be found in highly
predictable locations. Examples of crystalline material are salt, gold,
and the asbestos minerals.
It is beyond the scope of this method to describe the different
types of crystalline materials that can be found, or the full
description of the classes into which they can fall. However, some
general crystallography is provided below to give a foundation to the
procedures described.
With the exception of anthophyllite, all the asbestos minerals
belong to the monoclinic crystal type. The unit cell is the basic
repeating unit of the crystal and for monoclinic crystals can be
described as having three unequal sides, two 90 deg. angles and one
angle not equal to 90 deg.. The orthorhombic group, of which
anthophyllite is a member has three unequal sides and three 90 deg.
angles. The unequal sides are a consequence of the complexity of fitting
the different atoms into the unit cell. Although the atoms are in a
regular array, that array is not symmetrical in all directions. There is
long range order in the three major directions of the crystal. However,
the order is different in each of the three directions. This has the
effect that the index of refraction is different in each of the three
directions. Using polarized light, we can investigate the index of
refraction in each of the directions and identify the mineral or
material under investigation. The indices , , and
are used to identify the lowest, middle, and highest index of
refraction respectively. The x direction, associated with is
called the fast axis. Conversely, the z direction is associated with
and is the slow direction. Crocidolite has along the
fiber length making it ``length-fast''. The remainder of the asbestos
minerals have the axis along the fiber length. They are called
``length-slow''. This orientation to fiber length is used to aid in the
identification of asbestos.
4.3. Polarized Light Technique
Polarized light microscopy as described in this section uses the
phase-polar microscope described in Section 3.2. A phase contrast
microscope is fitted with two polarizing elements, one below and one
above the sample. The polarizers have their polarization directions at
right angles to each other. Depending on the tests performed, there may
be a compensator between these two polarizing elements. Light emerging
from a polarizing element has its electric vector pointing in the
polarization direction of the element. The light will not be
subsequently transmitted through a second element set at a right angle
to the first element. Unless the light is altered as it passes from one
element to the other, there is no transmission of light.
4.4. Angle of Extinction
Crystals which have different crystal regularity in two or three
main directions are said to be anisotropic. They have a different index
of refraction in each of the main directions. When such a crystal is
inserted between the crossed polars, the field of view is no longer dark
but shows the crystal in color. The color depends on the properties of
the crystal. The light acts as if it travels through the crystal along
the optical axes. If a crystal optical axis were lined up along one of
the polarizing directions (either the polarizer or the analyzer) the
light would appear to travel only in that direction, and it would blink
out or go dark. The difference in degrees between the fiber direction
and the angle at which it blinks out is called the angle of extinction.
When this angle can be measured, it is useful in identifying the
mineral. The procedure for measuring the angle of extinction is to first
identify the polarization direction in the microscope. A commercial
alignment slide can be used to establish the polarization directions or
use anthophyllite or another suitable mineral. This mineral has a zero
degree angle of extinction and will go dark to extinction as it aligns
with the polarization directions. When a fiber of anthophyllite has gone
to extinction, align the eyepiece reticle or graticule with the fiber so
that there is a visual cue as to the direction of polarization in the
field of view. Tape or otherwise secure the eyepiece in this position so
it will not shift.
After the polarization direction has been identified in the field of
view, move the particle of interest to the center of the field of view
and align it with the polarization direction. For fibers, align the
fiber along this direction. Note the angular reading of the rotating
stage. Looking at the particle, rotate
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the stage until the fiber goes dark or ``blinks out''. Again note the
reading of the stage. The difference in the first reading and the second
is an angle of extinction.
The angle measured may vary as the orientation of the fiber changes
about its long axis. Tables of mineralogical data usually report the
maximum angle of extinction. Asbestos forming minerals, when they
exhibit an angle of extinction, usually do show an angle of extinction
close to the reported maximum, or as appropriate depending on the
substitution chemistry.
4.5. Crossed Polars with Compensator
When the optical axes of a crystal are not lined up along one of the
polarizing directions (either the polarizer or the analyzer) part of the
light travels along one axis and part travels along the other visible
axis. This is characteristic of birefringent materials.
The color depends on the difference of the two visible indices of
refraction and the thickness of the crystal. The maximum difference
available is the difference between the and the
axes. This maximum difference is usually tabulated as the birefringence
of the crystal.
For this test, align the fiber at 45 deg. to the polarization
directions in order to maximize the contribution to each of the optical
axes. The colors seen are called retardation colors. They arise from the
recombination of light which has traveled through the two separate
directions of the crystal. One of the rays is retarded behind the other
since the light in that direction travels slower. On recombination, some
of the colors which make up white light are enhanced by constructive
interference and some are suppressed by destructive interference. The
result is a color dependent on the difference between the indices and
the thickness of the crystal. The proper colors, thicknesses, and
retardations are shown on a Michel-Levy chart. The three items,
retardation, thickness and birefringence are related by the following
relationship:
R=t(n--n)
R=retardation, t=crystal thickness in m, and
n,=indices of refraction.
Examination of the equation for asbestos minerals reveals that the
visible colors for almost all common asbestos minerals and fiber sizes
are shades of gray and black. The eye is relatively poor at
discriminating different shades of gray. It is very good at
discriminating different colors. In order to compensate for the low
retardation, a compensator is added to the light train between the
polarization elements. The compensator used for this test is a gypsum
plate of known thickness and birefringence. Such a compensator when
oriented at 45 deg. to the polarizer direction, provides a retardation
of 530 nm of the 530 nm wavelength color. This enhances the red color
and gives the background a characteristic red to red-magenta color. If
this ``full-wave'' compensator is in place when the asbestos preparation
is inserted into the light train, the colors seen on the fibers are
quite different. Gypsum, like asbestos has a fast axis and a slow axis.
When a fiber is aligned with its fast axis in the same direction as the
fast axis of the gypsum plate, the ray vibrating in the slow direction
is retarded by both the asbestos and the gypsum. This results in a
higher retardation than would be present for either of the two minerals.
The color seen is a second order blue. When the fiber is rotated 90 deg.
using the rotating stage, the slow direction of the fiber is now aligned
with the fast direction of the gypsum and the fast direction of the
fiber is aligned with the slow direction of the gypsum. Thus, one ray
vibrates faster in the fast direction of the gypsum, and slower in the
slow direction of the fiber; the other ray will vibrate slower in the
slow direction of the gypsum and faster in the fast direction of the
fiber. In this case, the effect is subtractive and the color seen is a
first order yellow. As long as the fiber thickness does not add
appreciably to the color, the same basic colors will be seen for all
asbestos types except crocidolite. In crocidolite the colors will be
weaker, may be in the opposite directions, and will be altered by the
blue absorption color natural to crocidolite. Hundreds of other
materials will give the same colors as asbestos, and therefore, this
test is not definitive for asbestos. The test is useful in
discriminating against fiberglass or other amorphous fibers such as some
synthetic fibers. Certain synthetic fibers will show retardation colors
different than asbestos; however, there are some forms of polyethylene
and aramid which will show morphology and retardation colors similar to
asbestos minerals. This test must be supplemented with a positive
identification test when birefringent fibers are present which can not
be excluded by morphology. This test is relatively ineffective for use
on fibers less than 1 m in diameter. For positive confirmation
TEM or SEM should be used if no larger bundles or fibers are visible.
4.6. Dispersion Staining
Dispersion microscopy or dispersion staining is the method of choice
for the identification of asbestos in bulk materials. Becke line
analysis is used by some laboratories and yields the same results as
does dispersion staining for asbestos and can be used in lieu of
dispersion staining. Dispersion staining is performed on the same
platform as the phase-polar analysis with the analyzer and compensator
removed. One polarizing element remains to define the direction of the
[[Page 71]]
light so that the different indices of refraction of the fibers may be
separately determined. Dispersion microscopy is a dark-field technique
when used for asbestos. Particles are imaged with scattered light. Light
which is unscattered is blocked from reaching the eye either by the back
field image mask in a McCrone objective or a back field image mask in
the phase condenser. The most convenient method is to use the rotating
phase condenser to move an oversized phase ring into place. The ideal
size for this ring is for the central disk to be just larger than the
objective entry aperture as viewed in the back focal plane. The larger
the disk, the less scattered light reaches the eye. This will have the
effect of diminishing the intensity of dispersion color and will shift
the actual color seen. The colors seen vary even on microscopes from the
same manufacturer. This is due to the different bands of wavelength
exclusion by different mask sizes. The mask may either reside in the
condenser or in the objective back focal plane. It is imperative that
the analyst determine by experimentation with asbestos standards what
the appropriate colors should be for each asbestos type. The colors
depend also on the temperature of the preparation and the exact
chemistry of the asbestos. Therefore, some slight differences from the
standards should be allowed. This is not a serious problem for
commercial asbestos uses. This technique is used for identification of
the indices of refraction for fibers by recognition of color. There is
no direct numerical readout of the index of refraction. Correlation of
color to actual index of refraction is possible by referral to published
conversion tables. This is not necessary for the analysis of asbestos.
Recognition of appropriate colors along with the proper morphology are
deemed sufficient to identify the commercial asbestos minerals. Other
techniques including SEM, TEM, and XRD may be required to provide
additional information in order to identify other types of asbestos.
Make a preparation in the suspected matching high dispersion oil,
e.g., n=1.550 for chrysotile. Perform the preliminary tests to determine
whether the fibers are birefringent or not. Take note of the
morphological character. Wavy fibers are indicative of chrysotile while
long, straight, thin, frayed fibers are indicative of amphibole
asbestos. This can aid in the selection of the appropriate matching oil.
The microscope is set up and the polarization direction is noted as in
Section 4.4. Align a fiber with the polarization direction. Note the
color. This is the color parallel to the polarizer. Then rotate the
fiber rotating the stage 90 deg. so that the polarization direction is
across the fiber. This is the perpendicular position. Again note the
color. Both colors must be consistent with standard asbestos minerals in
the correct direction for a positive identification of asbestos. If only
one of the colors is correct while the other is not, the identification
is not positive. If the colors in both directions are bluish-white, the
analyst has chosen a matching index oil which is higher than the correct
matching oil, e.g. the analyst has used n=1.620 where chrysotile is
present. The next lower oil (Section 3.5.) should be used to prepare
another specimen. If the color in both directions is yellow-white to
straw-yellow-white, this indicates that the index of the oil is lower
than the index of the fiber, e.g. the preparation is in n=1.550 while
anthophyllite is present. Select the next higher oil (Section 3.5.) and
prepare another slide. Continue in this fashion until a positive
identification of all asbestos species present has been made or all
possible asbestos species have been ruled out by negative results in
this test. Certain plant fibers can have similar dispersion colors as
asbestos. Take care to note and evaluate the morphology of the fibers or
remove the plant fibers in pre- preparation. Coating material on the
fibers such as carbonate or vinyl may destroy the dispersion color.
Usually, there will be some outcropping of fiber which will show the
colors sufficient for identification. When this is not the case, treat
the sample as described in Section 3.3. and then perform dispersion
staining. Some samples will yield to Becke line analysis if they are
coated or electron microscopy can be used for identification.
5. References
5.1. Crane, D.T., Asbestos in Air, OSHA method ID160, Revised
November 1992.
5.2. Ford, W.E., Dana's Textbook of Mineralogy; Fourth Ed.; John
Wiley and Son, New York, 1950, p. vii.
5.3. Selikoff,.I.J., Lee, D.H.K., Asbestos and Disease, Academic
Press, New York, 1978, pp. 3,20.
5.4. Women Inspectors of Factories. Annual Report for 1898, H.M.
Statistical Office, London, p. 170 (1898).
5.5. Selikoff, I.J., Lee, D.H.K., Asbestos and Disease, Academic
Press, New York, 1978, pp. 26,30.
5.6. Campbell, W.J., et al, Selected Silicate Minerals and Their
Asbestiform Varieties, United States Department of the Interior, Bureau
of Mines, Information Circular 8751, 1977.
5.7. Asbestos, Code of Federal Regulations, 29 CFR 1910.1001 and 29
CFR 1926.58.
5.8. National Emission Standards for Hazardous Air Pollutants;
Asbestos NESHAP Revision, Federal Register, Vol. 55, No. 224, 20
November 1990, p. 48410.
5.9. Ross, M. The Asbestos Minerals: Definitions, Description, Modes
of Formation, Physical and Chemical Properties and Health Risk to the
Mining Community, Nation Bureau of Standards Special Publication,
Washington, DC, 1977.
[[Page 72]]
5.10. Lilis, R., Fibrous Zeolites and Endemic Mesothelioma in
Cappadocia, Turkey, J. Occ Medicine, 1981, 23,(8),548-550.
5.11. Occupational Exposure to Asbestos--1972, U.S. Department of
Health, Education and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health, HSM-72-
10267.
5.12. Campbell, W.J., et al, Relationship of Mineral Habit to Size
Characteristics for Tremolite Fragments and Fibers, United States
Department of the Interior, Bureau of Mines, Information Circular 8367,
1979.
5.13. Mefford, D., DCM Laboratory, Denver, private communication,
July 1987.
5.14. Deer, W.A., Howie, R.A., Zussman, J., Rock Forming Minerals,
Longman, Thetford, UK, 1974.
5.15. Kerr, P.F., Optical Mineralogy; Third Ed. McGraw-Hill, New
York, 1959.
5.16. Veblen, D.R. (Ed.), Amphiboles and Other Hydrous Pyriboles--
Mineralogy, Reviews in Mineralogy, Vol 9A, Michigan, 1982, pp 1-102.
5.17. Dixon, W.C., Applications of Optical Microscopy in the
Analysis of Asbestos and Quartz, ACS Symposium Series, No. 120,
Analytical Techniques in Occupational Health Chemistry, 1979.
5.18. Polarized Light Microscopy, McCrone Research Institute,
Chicago, 1976.
5.19. Asbestos Identification, McCrone Research Institute, G & G
printers, Chicago, 1987.
5.20. McCrone, W.C., Calculation of Refractive Indices from
Dispersion Staining Data, The Microscope, No 37, Chicago, 1989.
5.21. Levadie, B. (Ed.), Asbestos and Other Health Related
Silicates, ASTM Technical Publication 834, ASTM, Philadelphia 1982.
5.22. Steel, E. and Wylie, A., Riordan, P.H. (Ed.), Mineralogical
Characteristics of Asbestos, Geology of Asbestos Deposits, pp. 93-101,
SME-AIME, 1981.
5.23. Zussman, J., The Mineralogy of Asbestos, Asbestos: Properties,
Applications and Hazards, pp. 45-67 Wiley, 1979.
[51 FR 22733, June 20, 1986, as amended at 51 FR 37004, Oct. 17, 1986;
52 FR 17754, 17755, May 12, 1987; 53 FR 35625, September 14, 1988; 54 FR
24334, June 7, 1989; 54 FR 29546, July 13, 1989; 54 FR 52027, Dec. 20,
1989, 55 FR 3731, Feb. 5, 1990; 55 FR 34710, Aug. 24, 1990; 57 FR 24330,
June 8, 1992; 59 FR 41057, Aug. 10, 1994; 60 FR 9625, Feb. 21, 1995; 60
FR 33344, June 28, 1995; 60 FR 33984-33987, June 29, 1995; 61 FR 5508,
Feb. 13, 1996; 61 FR 43457, Aug. 23, 1996; 63 FR 1285, Jan. 8, 1998]
Sec. 1910.1002 Coal tar pitch volatiles; interpretation of term.
As used in Sec. 1910.1000 (Table Z-1), coal tar pitch volatiles
include the fused polycyclic hydrocarbons which volatilize from the
distillation residues of coal, petroleum (excluding asphalt), wood, and
other organic matter. Asphalt (CAS 8052-42-4, and CAS 64742-93-4) is not
covered under the ``coal tar pitch volatiles'' standard.
[48 FR 2768, Jan. 21, 1983]
Sec. 1910.1003 13 Carcinogens (4-Nitrobiphenyl, etc.).
(a) Scope and application. (1) This section applies to any area in
which the 13 carcinogens addressed by this section are manufactured,
processed, repackaged, released, handled, or stored, but shall not apply
to transshipment in sealed containers, except for the labeling
requirements under paragraphs (e)(2), (3) and (4) of this section. The
13 carcinogens are the following:
4-Nitrobiphenyl, Chemical Abstracts Service Register Number (CAS No.)
92933;
alpha-Naphthylamine, CAS No. 134327;
methyl chloromethyl ether, CAS No. 107302;
3,'-Dichlorobenzidine (and its salts) CAS No. 91941;
bis-Chloromethyl ether, CAS No. 542881;
beta-Naphthylamine, CAS No. 91598;
Benzidine, CAS No. 92875;
4-Aminodiphenyl, CAS No. 92671;
Ethyleneimine, CAS No. 151564;
beta-Propiolactone, CAS No. 57578;
2-Acetylaminofluorene, CAS No. 53963;
4-Dimethylaminoazo-benezene, CAS No. 60117; and
N-Nitrosodimethylamine, CAS No. 62759.
(2) This section shall not apply to the following:
(i) Solid or liquid mixtures containing less than 0.1 percent by
weight or volume of 4-Nitrobiphenyl; methyl chloromethyl ether; bis-
chloromethyl ether; beta-Naphthylamine; benzidine or 4-Aminodiphenyl;
and
(ii) Solid or liquid mixtures containing less than 1.0 percent by
weight or volume of alpha-Naphthylamine; 3,'-Dichlorobenzidine (and its
salts); Ethyleneimine; beta-Propiolactone; 2-Acetylaminofluorene; 4-
Dimethylaminoazobenzene, or N-Nitrosodimethylamine.
(b) Definitions. For the purposes of this section:
Absolute filter is one capable of retaining 99.97 percent of a mono
disperse aerosol of 0.3 m particles.
Authorized employee means an employee whose duties require him to be
in the regulated area and who has been specifically assigned by the
employer.
[[Page 73]]
Clean change room means a room where employees put on clean clothing
and/or protective equipment in an environment free of the 13 carcinogens
addressed by this section. The clean change room shall be contiguous to
and have an entry from a shower room, when the shower room facilities
are otherwise required in this section.
Closed system means an operation involving a carcinogen addressed by
this section where containment prevents the release of the material into
regulated areas, non-regulated areas, or the external environment.
Decontamination means the inactivation of a carcinogen addressed by
this section or its safe disposal.
Director means the Director, National Institute for Occupational
Safety and Health, or any person directed by him or the Secretary of
Health and Human Services to act for the Director.
Disposal means the safe removal of the carcinogens addressed by this
section from the work environment.
Emergency means an unforeseen circumstance or set of circumstances
resulting in the release of a carcinogen addressed by this section that
may result in exposure to or contact with the material.
External environment means any environment external to regulated and
nonregulated areas.
Isolated system means a fully enclosed structure other than the
vessel of containment of a carcinogen addressed by this section that is
impervious to the passage of the material and would prevent the entry of
the carcinogen addressed by this section into regulated areas,
nonregulated areas, or the external environment, should leakage or
spillage from the vessel of containment occur.
Laboratory-type hood is a device enclosed on the three sides and the
top and bottom, designed and maintained so as to draw air inward at an
average linear face velocity of 150 feet per minute with a minimum of
125 feet per minute; designed, constructed, and maintained in such a way
that an operation involving a carcinogen addressed by this section
within the hood does not require the insertion of any portion of any
employee's body other than his hands and arms.
Nonregulated area means any area under the control of the employer
where entry and exit is neither restricted nor controlled.
Open-vessel system means an operation involving a carcinogen
addressed by this section in an open vessel that is not in an isolated
system, a laboratory-type hood, nor in any other system affording
equivalent protection against the entry of the material into regulated
areas, non-regulated areas, or the external environment.
Protective clothing means clothing designed to protect an employee
against contact with or exposure to a carcinogen addressed by this
section.
Regulated area means an area where entry and exit is restricted and
controlled.
(c) Requirements for areas containing a carcinogen addressed by this
section. A regulated area shall be established by an employer where a
carcinogen addressed by this section is manufactured, processed, used,
repackaged, released, handled or stored. All such areas shall be
controlled in accordance with the requirements for the following
category or categories describing the operation involved:
(1) Isolated systems. Employees working with a carcinogen addressed
by this section within an isolated system such as a ``glove box'' shall
wash their hands and arms upon completion of the assigned task and
before engaging in other activities not associated with the isolated
system.
(2) Closed system operation. (i) Within regulated areas where the
carcinogens addressed by this section are stored in sealed containers,
or contained in a closed system, including piping systems, with any
sample ports or openings closed while the carcinogens addressed by this
section are contained within, access shall be restricted to authorized
employees only.
(ii) Employees exposed to 4-Nitrobiphenyl; alpha-Naphthylamine; 3,'-
Dichlorobenzidine (and its salts); beta-Naphthylamine; benzidine; 4-
Aminodiphenyl; 2-Acetylaminofluorene; 4-Dimethylaminoazo-benzene; and N-
Nitrosodimethylamine shall be required to wash hands, forearms, face,
[[Page 74]]
and neck upon each exit from the regulated areas, close to the point of
exit, and before engaging in other activities.
(3) Open-vessel system operations. Open-vessel system operations as
defined in paragraph (b)(13) of this section are prohibited.
(4) Transfer from a closed system, charging or discharging point
operations, or otherwise opening a closed system. In operations
involving ``laboratory-type hoods,'' or in locations where the
carcinogens addressed by this section are contained in an otherwise
``closed system,'' but is transferred, charged, or discharged into other
normally closed containers, the provisions of this paragraph shall
apply.
(i) Access shall be restricted to authorized employees only.
(ii) Each operation shall be provided with continuous local exhaust
ventilation so that air movement is always from ordinary work areas to
the operation. Exhaust air shall not be discharged to regulated areas,
nonregulated areas or the external environment unless decontaminated.
Clean makeup air shall be introduced in sufficient volume to maintain
the correct operation of the local exhaust system.
(iii) Employees shall be provided with, and required to wear, clean,
full body protective clothing (smocks, coveralls, or long-sleeved shirt
and pants), shoe covers and gloves prior to entering the regulated area.
(iv) Employees engaged in handling operations involving the
carcinogens addressed by this section must be provided with, and
required to wear and use a half-face filter-type respirator with filters
for dusts, mists, and fumes, or air-purifying canisters or cartridges. A
respirator affording higher levels of protection than this respirator
may be substituted.
(v) Prior to each exit from a regulated area, employees shall be
required to remove and leave protective clothing and equipment at the
point of exit and at the last exit of the day, to place used clothing
and equipment in impervious containers at the point of exit for purposes
of decontamination or disposal. The contents of such impervious
containers shall be identified, as required under paragraphs (e) (2),
(3), and (4) of this section.
(vi) Drinking fountains are prohibited in the regulated area.
(vii) Employees shall be required to wash hands, forearms, face, and
neck on each exit from the regulated area, close to the point of exit,
and before engaging in other activities and employees exposed to 4-
Nitrobiphenyl; alpha-Naphthylamine; 3,'-Dichlorobenzidine (and its
salts); beta-Naphthylamine; Benzidine; 4-Aminodiphenyl; 2-
Acetylaminofluorene; 4-Dimethylaminoazo-benzene; and N-
Nitrosodimethylamine shall be required to shower after the last exit of
the day.
(5) Maintenance and decontamination activities. In cleanup of leaks
of spills, maintenance, or repair operations on contaminated systems or
equipment, or any operations involving work in an area where direct
contact with a carcinogen addressed by this section could result, each
authorized employee entering that area shall:
(i) Be provided with and required to wear clean, impervious
garments, including gloves, boots, and continuous-air supplied hood in
accordance with Sec. 1910.134;
(ii) Be decontaminated before removing the protective garments and
hood;
(iii) Be required to shower upon removing the protective garments
and hood.
(d) General regulated area requirements--(1) Respirator program. The
employer must implement a respiratory protection program in accordance
with 29 CFR 1910.134 (b), (c), (d) (except (d)(1)(iii) and (iv), and
(d)(3)), and (e) through (m).
(2) Emergencies. In an emergency, immediate measures including, but
not limited to, the requirements of paragraphs (d)(2) (i) through (v) of
this section shall be implemented.
(i) The potentially affected area shall be evacuated as soon as the
emergency has been determined.
(ii) Hazardous conditions created by the emergency shall be
eliminated and the potentially affected area shall be decontaminated
prior to the resumption of normal operations.
(iii) Special medical surveillance by a physician shall be
instituted within 24
[[Page 75]]
hours for employees present in the potentially affected area at the time
of the emergency. A report of the medical surveillance and any treatment
shall be included in the incident report, in accordance with paragraph
(f)(2) of this section.
(iv) Where an employee has a known contact with a carcinogen
addressed by this section, such employee shall be required to shower as
soon as possible, unless contraindicated by physical injuries.
(v) An incident report on the emergency shall be reported as
provided in paragraph (f)(2) of this section.
(vi) Emergency deluge showers and eyewash fountains supplied with
running potable water shall be located near, within sight of, and on the
same level with locations where a direct exposure to Ethyleneimine or
beta-Propiolactone only would be most likely as a result of equipment
failure or improper work practice.
(3) Hygiene facilities and practices. (i) Storage or consumption of
food, storage or use of containers of beverages, storage or application
of cosmetics, smoking, storage of smoking materials, tobacco products or
other products for chewing, or the chewing of such products are
prohibited in regulated areas.
(ii) Where employees are required by this section to wash, washing
facilities shall be provided in accordance with Sec. 1910.141(d) (1) and
(2) (ii) through (vii).
(iii) Where employees are required by this section to shower, shower
facilities shall be provided in accordance with Sec. 1910.141(d)(3).
(iv) Where employees wear protective clothing and equipment, clean
change rooms shall be provided for the number of such employees required
to change clothes, in accordance with Sec. 1910.141(e).
(v) Where toilets are in regulated areas, such toilets shall be in a
separate room.
(4) Contamination control. (i) Except for outdoor systems, regulated
areas shall be maintained under pressure negative with respect to
nonregulated areas. Local exhaust ventilation may be used to satisfy
this requirement. Clean makeup air in equal volume shall replace air
removed.
(ii) Any equipment, material, or other item taken into or removed
from a regulated area shall be done so in a manner that does not cause
contamination in nonregulated areas or the external environment.
(iii) Decontamination procedures shall be established and
implemented to remove carcinogens addressed by this section from the
surfaces of materials, equipment, and the decontamination facility.
(iv) Dry sweeping and dry mopping are prohibited for 4-
Nitrobiphenyl; alpha-Naphthylamine; 3,'-Dichlorobenzidine (and its
salts); beta-Naphthylamine; Benzidine; 4-Aminodiphenyl; 2-
Acetylaminofluorene; 4-Dimethylaminoazo-benzene and N-
Nitrosodimethylamine.
(e) Signs, information and training--(1) Signs--(i) Entrances to
regulated areas shall be posted with signs bearing the legend:
CANCER-SUSPECT AGENT
AUTHORIZED PERSONNEL ONLY
(ii) Entrances to regulated areas containing operations covered in
paragraph (c)(5) of this section shall be posted with signs bearing the
legend:
CANCER-SUSPECT AGENT EXPOSED IN THIS AREA
IMPERVIOUS SUIT INCLUDING GLOVES, BOOTS, AND AIR-SUPPLIED HOOD REQUIRED
AT ALL TIMES
AUTHORIZED PERSONNEL ONLY
(iii) Appropriate signs and instructions shall be posted at the
entrance to, and exit from, regulated areas, informing employees of the
procedures that must be followed in entering and leaving a regulated
area.
(2) Container contents identification. (i) Containers of a
carcinogen addressed by this section and containers required under
paragraphs (c)(4)(v) and (c)(6) (vii)(B) and (viii)(B) of this section
that are accessible only to and handled only by authorized employees, or
by other employees trained in accordance with paragraph (e)(5) of this
section, may have contents identification limited to
[[Page 76]]
a generic or proprietary name or other proprietary identification of the
carcinogen and percent.
(ii) Containers of a carcinogen addressed by this section and
containers required under paragraphs (c)(4)(v) and (c)(6) (vii)(B) and
(viii)(B) of this section that are accessible to or handled by employees
other than authorized employees or employees trained in accordance with
paragraph (e)(5) of this section shall have contents identification that
includes the full chemical name and Chemical Abstracts Service Registry
number as listed in paragraph (a)(1) of this section.
(iii) Containers shall have the warning words ``CANCER-SUSPECT
AGENT'' displayed immediately under or adjacent to the contents
identification.
(iv) Containers whose contents are carcinogens addressed by this
section with corrosive or irritating properties shall have label
statements warning of such hazards noting, if appropriate, particularly
sensitive or affected portions of the body.
(3) Lettering. Lettering on signs and instructions required by
paragraph (e)(1) shall be a minimum letter height of 2 inches (5 cm).
Labels on containers required under this section shall not be less than
one-half the size of the largest lettering on the package, and not less
than 8-point type in any instance. Provided, That no such required
lettering need be more than 1 inch (2.5 cm) in height.
(4) Prohibited statements. No statement shall appear on or near any
required sign, label, or instruction that contradicts or detracts from
the effect of any required warning, information, or instruction.
(5) Training and indoctrination. (i) Each employee prior to being
authorized to enter a regulated area, shall receive a training and
indoctrination program including, but not necessarily limited to:
(A) The nature of the carcinogenic hazards of a carcinogen addressed
by this section, including local and systemic toxicity;
(B) The specific nature of the operation involving a carcinogen
addressed by this section that could result in exposure;
(C) The purpose for and application of the medical surveillance
program, including, as appropriate, methods of self-examination;
(D) The purpose for and application of decontamination practices and
purposes;
(E) The purpose for and significance of emergency practices and
procedures;
(F) The employee's specific role in emergency procedures;
(G) Specific information to aid the employee in recognition and
evaluation of conditions and situations which may result in the release
of a carcinogen addressed by this section;
(H) The purpose for and application of specific first aid procedures
and practices;
(I) A review of this section at the employee's first training and
indoctrination program and annually thereafter.
(ii) Specific emergency procedures shall be prescribed, and posted,
and employees shall be familiarized with their terms, and rehearsed in
their application.
(iii) All materials relating to the program shall be provided upon
request to authorized representatives of the Assistant Secretary and the
Director.
(f) Reports--(1) Operations. The information required in paragraphs
(f)(1) (i) through (iv) of this section shall be reported in writing to
the nearest OSHA Area Director. Any changes in such information shall be
similarly reported in writing within 15 calendar days of such change:
(i) A brief description and in-plant location of the area(s)
regulated and the address of each regulated area;
(ii) The name(s) and other identifying information as to the
presence of a carcinogen addressed by this section in each regulated
area;
(iii) The number of employees in each regulated area, during normal
operations including maintenance activities; and
(iv) The manner in which carcinogens addressed by this section are
present in each regulated area; for example, whether it is manufactured,
processed, used, repackaged, released, stored, or otherwise handled.
(2) Incidents. Incidents that result in the release of a carcinogen
addressed
[[Page 77]]
by this section into any area where employees may be potentially exposed
shall be reported in accordance with this paragraph.
(i) A report of the occurrence of the incident and the facts
obtainable at that time including a report on any medical treatment of
affected employees shall be made within 24 hours to the nearest OSHA
Area Director.
(ii) A written report shall be filed with the nearest OSHA Area
Director within 15 calendar days thereafter and shall include:
(A) A specification of the amount of material released, the amount
of time involved, and an explanation of the procedure used in
determining this figure;
(B) A description of the area involved, and the extent of known and
possible employee exposure and area contamination;
(C) A report of any medical treatment of affected employees, and any
medical surveillance program implemented; and
(D) An analysis of the circumstances of the incident and measures
taken or to be taken, with specific completion dates, to avoid further
similar releases.
(g) Medical surveillance. At no cost to the employee, a program of
medical surveillance shall be established and implemented for employees
considered for assignment to enter regulated areas, and for authorized
employees.
(1) Examinations. (i) Before an employee is assigned to enter a
regulated area, a preassignment physical examination by a physician
shall be provided. The examination shall include the personal history of
the employee, family and occupational background, including genetic and
environmental factors.
(ii) Authorized employees shall be provided periodic physical
examinations, not less often than annually, following the preassignment
examination.
(iii) In all physical examinations, the examining physician shall
consider whether there exist conditions of increased risk, including
reduced immunological competence, those undergoing treatment with
steroids or cytotoxic agents, pregnancy, and cigarette smoking.
(2) Records. (i) Employers of employees examined pursuant to this
paragraph shall cause to be maintained complete and accurate records of
all such medical examinations. Records shall be maintained for the
duration of the employee's employment. Upon termination of the
employee's employment, including retirement or death, or in the event
that the employer ceases business without a successor, records, or
notarized true copies thereof, shall be forwarded by registered mail to
the Director.
(ii) Records required by this paragraph shall be provided upon
request to employees, designated representatives, and the Assistant
Secretary in accordance with 29 CFR 1910.20 (a) through (e) and (g)
through (i). These records shall also be provided upon request to the
Director.
(iii) Any physician who conducts a medical examination required by
this paragraph shall furnish to the employer a statement of the
employee's suitability for employment in the specific exposure.
[61 FR 9242, Mar. 7, 1996, as amended at 63 FR 1286, Jan. 8, 1998; 63 FR
20099, Apr. 23, 1998]
Sec. 1910.1004 alpha-Naphthylamine.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1005 [Reserved]
Sec. 1910.1006 Methyl chloromethyl ether.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1007 3,'-Dichlorobenzidine (and its salts).
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1008 bis-Chloromethyl ether.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1009 beta-Naphthylamine.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
[[Page 78]]
Sec. 1910.1010 Benzidine.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1011 4-Aminodiphenyl.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1012 Ethyleneimine.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1013 beta-Propiolactone.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1014 2-Acetylaminofluorene.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1015 4-Dimethylaminoazobenzene.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1016 N-Nitrosodimethylamine.
See Sec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1017 Vinyl chloride.
(a) Scope and application. (1) This section includes requirements
for the control of employee exposure to vinyl chloride (chloroethene),
Chemical Abstracts Service Registry No. 75014.
(2) This section applies to the manufacture, reaction, packaging,
repackaging, storage, handling or use of vinyl chloride or polyvinyl
chloride, but does not apply to the handling or use of fabricated
products made of polyvinyl chloride.
(3) This section applies to the transportation of vinyl chloride or
polyvinyl chloride except to the extent that the Department of
Transportation may regulate the hazards covered by this section.
(b) Definitions. (1) Action level means a concentration of vinyl
chloride of 0.5 ppm averaged over an 8-hour work day.
(2) Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or his
designee.
(3) Authorized person means any person specifically authorized by
the employer whose duties require him to enter a regulated area or any
person entering such an area as a designated representative of employees
for the purpose of exercising an opportunity to observe monitoring and
measuring procedures.
(4) Director means the Director, National Institute for Occupational
Safety and Health, U.S. Department of Health and Human Services, or his
designee.
(5) Emergency means any occurrence such as, but not limited to,
equipment failure, or operation of a relief device which is likely to,
or does, result in massive release of vinyl chloride.
(6) Fabricated product means a product made wholly or partly from
polyvinyl chloride, and which does not require further processing at
temperatures, and for times, sufficient to cause mass melting of the
polyvinyl chloride resulting in the release of vinyl chloride.
(7) Hazardous operation means any operation, procedure, or activity
where a release of either vinyl chloride liquid or gas might be expected
as a consequence of the operation or because of an accident in the
operation, which would result in an employee exposure in excess of the
permissible exposure limit.
(8) OSHA Area Director means the Director for the Occupational
Safety and Health Administration Area Office having jurisdiction over
the geographic area in which the employer's establishment is located.
(9) Polyvinyl chloride means polyvinyl chloride homopolymer or
copolymer before such is converted to a fabricated product.
(10) Vinyl chloride means vinyl chloride monomer.
(c) Permissible exposure limit. (1) No employee may be exposed to
vinyl chloride at concentrations greater than 1 ppm averaged over any 8-
hour period, and
(2) No employee may be exposed to vinyl chloride at concentrations
greater than 5 ppm averaged over any period not exceeding 15 minutes.
[[Page 79]]
(3) No employee may be exposed to vinyl chloride by direct contact
with liquid vinyl chloride.
(d) Monitoring. (1) A program of initial monitoring and measurement
shall be undertaken in each establishment to determine if there is any
employee exposed, without regard to the use of respirators, in excess of
the action level.
(2) Where a determination conducted under paragraph (d)(1) of this
section shows any employee exposures, without regard to the use of
respirators, in excess of the action level, a program for determining
exposures for each such employee shall be established. Such a program:
(i) Shall be repeated at least monthly where any employee is
exposed, without regard to the use of respirators, in excess of the
permissible exposure limit.
(ii) Shall be repeated not less than quarterly where any employee is
exposed, without regard to the use of respirators, in excess of the
action level.
(iii) May be discontinued for any employee only when at least two
consecutive monitoring determinations, made not less than 5 working days
apart, show exposures for that employee at or below the action level.
(3) Whenever there has been a production, process or control change
which may result in an increase in the release of vinyl chloride, or the
employer has any other reason to suspect that any employee may be
exposed in excess of the action level, a determination of employee
exposure under paragraph (d)(1) of this section shall be performed.
(4) The method of monitoring and measurement shall have an accuracy
(with a confidence level of 95 percent) of not less than plus or minus
50 percent from 0.25 through 0.5 ppm, plus or minus 35 percent from over
0.5 ppm through 1.0 ppm, and plus or minus 25 percent over 1.0 ppm.
(Methods meeting these accuracy requirements are available in the
``NIOSH Manual of Analytical Methods'').
(5) Employees or their designated representatives shall be afforded
reasonable opportunity to observe the monitoring and measuring required
by this paragraph.
(e) Regulated area. (1) A regulated area shall be established where:
(i) Vinyl chloride or polyvinyl chloride is manufactured, reacted,
repackaged, stored, handled or used; and
(ii) Vinyl chloride concentrations are in excess of the permissible
exposure limit.
(2) Access to regulated areas shall be limited to authorized
persons.
(f) Methods of compliance. Employee exposures to vinyl chloride
shall be controlled to at or below the permissible exposure limit
provided in paragraph (c) of this section by engineering, work practice,
and personal protective controls as follows:
(1) Feasible engineering and work practice controls shall
immediately be used to reduce exposures to at or below the permissible
exposure limit.
(2) Wherever feasible engineering and work practice controls which
can be instituted immediately are not sufficient to reduce exposures to
at or below the permissible exposure limit, they shall nonetheless be
used to reduce exposures to the lowest practicable level, and shall be
supplemented by respiratory protection in accordance with paragraph (g)
of this section. A program shall be established and implemented to
reduce exposures to at or below the permissible exposure limit, or to
the greatest extent feasible, solely by means of engineering and work
practice controls, as soon as feasible.
(3) Written plans for such a program shall be developed and
furnished upon request for examination and copying to authorized
representatives of the Assistant Secretary and the Director. Such plans
shall be updated at least every six months.
(g) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide
respirators that comply with the requirements of this paragraph.
(2) Respirator program. The employer must implement a respiratory
protection program in accordance with 29 CFR 1910.134 (b) through (d)
(except (d)(1)(iii), and (d)(3)(iii)(B)(1) and (2)), and (f) through
(m).
(3) Respirator selection. (i) Respirators must be selected from the
following table:
[[Page 80]]
------------------------------------------------------------------------
Atmospheric concentration of
vinyl chloride Required apparatus
------------------------------------------------------------------------
(i) Unknown, or above 3,600 p/ Open-circuit, self-contained breathing
m. apparatus, pressure demand type, with
full facepiece.
(ii) Not over 3,600 p/m...... (A) Combination type C supplied air
respirator, pressure demand type, with
full or half facepiece, and auxiliary
self-contained air supply; or
(iii) Not over 1,000 p/m..... (B) Combination type, supplied air
respirator continuous flow type, with
full or half facepiece, and auxiliary
self-contained air supply. Type C,
supplied air respirator, continuous flow
type, with full or half facepiece,
helmet or hood.
(iv) Not over 100 p/m........ (A) Combination type C supplied air
respirator demand type, with full
facepiece, and auxiliary self-contained
air supply; or
(B) Open-circuit self-contained breathing
apparatus with full facepiece, in demand
mode; or
Type (C) supplied air respirator, demand
type, with full facepiece.
(v) Not over 25 p/m.......... (A) A powered air-purifying respirator
with hood, helmet, full or half
facepiece, and a canister which provides
a service life of at least 4 hours for
concentrations of vinyl chloride up to
25 p/m, or
(B) Gas mask, front- or back-mounted
canister which provides a service life
of at least 4 hours for concentrations
of vinyl chloride up to 25 p/m.
(vi) Not over 10 p/m......... (A) Combination type C supplied-air
respirator, demand type, with half
facepiece, and auxiliary self-contained
air supply; or
(B) Type C supplied-air respirator,
demand type, with half facepiece; or
(C) Any chemical cartridge respirator
with an organic vapor cartridge which
provides a service life of at least 1
hour for concentrations of vinyl
chloride up to 10 p/m.
------------------------------------------------------------------------
(ii) When air-purifying respirators are used:
(A) Air-purifying canisters or cartridges must be replaced prior to
the expiration of their service life or the end of the shift in which
they are first used, whichever occurs first.
(B) A continuous-monitoring and alarm system must be provided when
concentrations of vinyl chloride could reasonably exceed the allowable
concentrations for the devices in use. Such a system must be used to
alert employees when vinyl chloride concentrations exceed the allowable
concentrations for the devices in use.
(iii) Respirators specified for higher concentrations may be used
for lower concentrations.
(h) Hazardous operations. (1) Employees engaged in hazardous
operations, including entry of vessels to clean polyvinyl chloride
residue from vessel walls, shall be provided and required to wear and
use;
(i) Respiratory protection in accordance with paragraphs (c) and (g)
of this section; and
(ii) Protective garments to prevent skin contact with liquid vinyl
chloride or with polyvinyl chloride residue from vessel walls. The
protective garments shall be selected for the operation and its possible
exposure conditions.
(2) Protective garments shall be provided clean and dry for each
use.
(i) Emergency situations. A written operational plan for emergency
situations shall be developed for each facility storing, handling, or
otherwise using vinyl chloride as a liquid or compressed gas.
Appropriate portions of the plan shall be implemented in the event of an
emergency. The plan shall specifically provide that:
(1) Employees engaged in hazardous operations or correcting
situations of existing hazardous releases shall be equipped as required
in paragraph (h) of this section;
(2) Other employees not so equipped shall evacuate the area and not
return until conditions are controlled by the methods required in
paragraph (f) of this section and the emergency is abated.
(j) Training. Each employee engaged in vinyl chloride or polyvinyl
chloride operations shall be provided training in a program relating to
the hazards of vinyl chloride and precautions for its safe use.
(1) The program shall include:
(i) The nature of the health hazard from chronic exposure to vinyl
chloride including specifically the carcinogenic hazard;
(ii) The specific nature of operations which could result in
exposure to vinyl chloride in excess of the permissible limit and
necessary protective steps;
[[Page 81]]
(iii) The purpose for, proper use, and limitations of respiratory
protective devices;
(iv) The fire hazard and acute toxicity of vinyl chloride, and the
necessary protective steps;
(v) The purpose for and a description of the monitoring program;
(vi) The purpose for, and a description of, the medical surveillance
program;
(vii) Emergency procedures;
(viii) Specific information to aid the employee in recognition of
conditions which may result in the release of vinyl chloride; and
(ix) A review of this standard at the employee's first training and
indoctrination program, and annually thereafter.
(2) All materials relating to the program shall be provided upon
request to the Assistant Secretary and the Director.
(k) Medical surveillance. A program of medical surveillance shall be
instituted for each employee exposed, without regard to the use of
respirators, to vinyl chloride in excess of the action level. The
program shall provide each such employee with an opportunity for
examinations and tests in accordance with this paragraph. All medical
examinations and procedures shall be performed by or under the
supervision of a licensed physician, and shall be provided without cost
to the employee.
(1) At the time of initial assignment, or upon institution of
medical surveillance;
(i) A general physical examination shall be performed, with specific
attention to detecting enlargement of liver, spleen or kidneys, or
dysfunction in these organs, and for abnormalities in skin, connective
tissues and the pulmonary system (See Appendix A).
(ii) A medical history shall be taken, including the following
topics:
(A) Alcohol intake;
(B) Past history of hepatitis;
(C) Work history and past exposure to potential hepatotoxic agents,
including drugs and chemicals;
(D) Past history of blood transfusions; and
(E) Past history of hospitalizations.
(iii) A serum specimen shall be obtained and determinations made of:
(A) Total bilirubin;
(B) Alkaline phosphatase;
(C) Serum glutamic oxalacetic transaminase (SGOT);
(D) Serum glutamic pyruvic transaminase (SGPT); and
(E) Gamma glustamyl transpeptidase.
(2) Examinations provided in accordance with this paragraph shall be
performed at least:
(i) Every 6 months for each employee who has been employed in vinyl
chloride or polyvinyl chloride manufacturing for 10 years or longer; and
(ii) Annually for all other employees.
(3) Each employee exposed to an emergency shall be afforded
appropriate medical surveillance.
(4) A statement of each employee's suitability for continued
exposure to vinyl chloride including use of protective equipment and
respirators, shall be obtained from the examining physician promptly
after any examination. A copy of the physician's statement shall be
provided each employee.
(5) If any employee's health would be materially impaired by
continued exposure, such employee shall be withdrawn from possible
contact with vinyl chloride.
(6) Laboratory analyses for all biological specimens included in
medical examinations shall be performed in laboratories licensed under
42 CFR Part 74.
(7) If the examining physician determines that alternative medical
examinations to those required by paragraph (k)(1) of this section will
provide at least equal assurance of detecting medical conditions
pertinent to the exposure to vinyl chloride, the employer may accept
such alternative examinations as meeting the requirements of paragraph
(k)(1) of this section, if the employer obtains a statement from the
examining physician setting forth the alternative examinations and the
rationale for substitution. This statement shall be available upon
request for examination and copying to authorized representatives of the
Assistant Secretary and the Director.
(l) Signs and labels. (1) Entrances to regulated areas shall be
posted with legible signs bearing the legend:
[[Page 82]]
Cancer-Suspect Agent Area Authorized Personnel Only
(2) Areas containing hazardous operations or where an emergency
currently exists shall be posted with legible signs bearing the legend:
Cancer-Suspect Agent in This Area Protective Equipment Required
Authorized Personnel Only
(3) Containers of polyvinyl chloride resin waste from reactors or
other waste contaminated with vinyl chloride shall be legibly labeled:
Contaminated With Vinyl Chloride
Cancer-Suspect Agent
(4) Containers of polyvinyl chloride shall be legibly labeled:
Polyvinyl Chloride (or Trade Name)
Contains
Vinyl Chloride
Vinyl Chloride is a Cancer-Suspect Agent
(5) Containers of vinyl chloride shall be legibly labeled either:
(i)
Vinyl Chloride
Extremely Flammable Gas Under Pressure
Cancer Suspect Agent
or (ii) In accordance with 49 CFR Parts 170 through 189, with the
additional legend:
Cancer-Suspect Agent
applied near the label or placard.
(6) No statement shall appear on or near any required sign, label or
instruction which contradicts or detracts from the effect of, any
required warning, information or instruction.
(m) Records. (1) All records maintained in accordance with this
section shall include the name and social security number of each
employee where relevant.
(2) Records of required monitoring and measuring and medical records
shall be provided upon request to employees, designated representatives,
and the Assistant Secretary in accordance with 29 CFR 1910.20 (a)
through (e) and (g) through (i). These records shall be provided upon
request to the Director. Authorized personnel rosters shall also be
provided upon request to the Assistant Secretary and the Director.
(i) Monitoring and measuring records shall:
(A) State the date of such monitoring and measuring and the
concentrations determined and identify the instruments and methods used;
(B) Include any additional information necessary to determine
individual employee exposures where such exposures are determined by
means other than individual monitoring of employees; and
(C) Be maintained for not less than 30 years.
(ii) [Reserved]
(iii) Medical records shall be maintained for the duration of the
employment of each employee plus 20 years, or 30 years, whichever is
longer.
(3) In the event that the employer ceases to do business and there
is no successor to receive and retain his records for the prescribed
period, these records shall be transmitted by registered mail to the
Director, and each employee individually notified in writing of this
transfer. The employer shall also comply with any additional
requirements set forth in 29 CFR 1910.20(h).
(n) Reports. (1) Not later than 1 month after the establishment of a
regulated area, the following information shall be reported to the OSHA
Area Director. Any changes to such information shall be reported within
15 days.
(i) The address and location of each establishment which has one or
more regulated areas; and
(ii) The number of employees in each regulated area during normal
operations, including maintenance.
(2) Emergencies, and the facts obtainable at that time, shall be
reported within 24 hours to the OSHA Area Director. Upon request of the
Area Director, the employer shall submit additional information in
writing relevant to the nature and extent of employee
[[Page 83]]
exposures and measures taken to prevent future emergencies of similar
nature.
(3) Within 10 working days following any monitoring and measuring
which discloses that any employee has been exposed, without regard to
the use of respirators, in excess of the permissible exposure limit,
each such employee shall be notified in writing of the results of the
exposure measurement and the steps being taken to reduce the exposure to
within the permissible exposure limit.
(o) Effective dates. (1) Until April 1, 1975, the provisions
currently set forth in Sec. 1910.93q of this part shall apply.
(2) Effective April 1, 1975, the provisions set forth in
Sec. 1910.93q of this part shall apply.
Appendix A to Sec. 1910.1017--Supplementary Medical Information
When required tests under paragraph (k)(1) of this section show
abnormalities, the tests should be repeated as soon as practicable,
preferably within 3 to 4 weeks. If tests remain abnormal, consideration
should be given to withdrawal of the employee from contact with vinyl
chloride, while a more comprehensive examination is made.
Additional tests which may be useful:
A. For kidney dysfunction: urine examination for albumin, red blood
cells, and exfoliative abnormal cells.
B. Pulmonary system: Forced vital capacity, Forced expiratory volume
at 1 second, and chest roentgenogram (posterior-anterior, 14 x 17
inches).
C. Additional serum tests: Lactic acid dehydrogenase, lactic acid
dehydrogenase isoenzyme, protein determination, and protein
electrophoresis.
D. For a more comprehensive examination on repeated abnormal serum
tests: Hepatitis B antigen, and liver scanning.
[39 FR 35896, Oct. 4, 1974; 39 FR 41848, Dec. 3, 1974, as amended at 40
FR 13211, Mar. 25, 1975. Redesignated at 40 FR 23072, May 28, 1975 and
amended at 43 FR 49751, Oct. 24, 1978; 45 FR 35282, May 23, 1980; 54 FR
24334, June 7, 1989; 58 FR 35310, June 30, 1993; 61 FR 5508, Feb. 13,
1996; 63 FR 1286, Jan. 8, 1998]
Sec. 1910.1018 Inorganic arsenic.
(a) Scope and application. This section applies to all occupational
exposures to inorganic arsenic except that this section does not apply
to employee exposures in agriculture or resulting from pesticide
application, the treatment of wood with preservatives or the utilization
of arsenically preserved wood.
(b) Definitions. Action level means a concentration of inorganic
arsenic of 5 micrograms per cubic meter of air (5 g/
m3) averaged over any eight (8) hour period.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the
employer whose duties require the person to enter a regulated area, or
any person entering such an area as a designated representative of
employees for the purpose of exercising the right to observe monitoring
and measuring procedures under paragraph (e) of this section.
Director means the Director, National Institute for Occupational
Safety and Health, U.S. Department of Health and Human Services, or
designee.
Inorganic arsenic means copper aceto- arsenite and all inorganic
compounds containing arsenic except arsine, measured as arsenic (As).
(c) Permissible exposure limit. The employer shall assure that no
employee is exposed to inorganic arsenic at concentrations greater than
10 micrograms per cubic meter of air (10 g/m3),
averaged over any 8-hour period.
(d) Notification of use. (1) By October 1, 1978 or within 60 days
after the introduction of inorganic arsenic into the workplace, every
employer who is required to establish a regulated area in his workplaces
shall report in writing to the OSHA area office for each such workplace:
(i) The address of each such workplace;
(ii) The approximate number of employees who will be working in
regulated areas; and
(iii) A brief summary of the operations creating the exposure and
the actions which the employer intends to take to reduce exposures.
(2) Whenever there has been a significant change in the information
required by paragraph (d)(1) of this section the employer shall report
the changes in writing within 60 days to the OSHA area office.
[[Page 84]]
(e) Exposure monitoring--(1) General. (i) Determinations of airborne
exposure levels shall be made from air samples that are representative
of each employee's exposure to inorganic arsenic over an eight (8) hour
period.
(ii) For the purposes of this section, employee exposure is that
exposure which would occur if the employee were not using a respirator.
(iii) The employer shall collect full shift (for at least 7
continuous hours) personal samples including at least one sample for
each shift for each job classification in each work area.
(2) Initial monitoring. Each employer who has a workplace or work
operation covered by this standard shall monitor each such workplace and
work operation to accurately determine the airborne concentration of
inorganic arsenic to which employees may be exposed.
(3) Frequency. (i) If the initial monitoring reveals employee
exposure to be below the action level the measurements need not be
repeated except as otherwise provided in paragraph (e)(4) of this
section.
(ii) If the initial monitoring, required by this section, or
subsequent monitoring reveals employee exposure to be above the
permissible exposure limit, the employer shall repeat monitoring at
least quarterly.
(iii) If the initial monitoring, required by this section, or
subsequent monitoring reveals employee exposure to be above the action
level and below the permissible exposure limit the employer shall repeat
monitoring at least every six months.
(iv) The employer shall continue monitoring at the required
frequency until at least two consecutive measurements, taken at least
seven (7) days apart, are below the action level at which time the
employer may discontinue monitoring for that employee until such time as
any of the events in paragraph (e)(4) of this section occur.
(4) Additional monitoring. Whenever there has been a production,
process, control or personal change which may result in new or
additional exposure to inorganic arsenic, or whenever the employer has
any other reason to suspect a change which may result in new or
additional exposures to inorganic arsenic, additional monitoring which
complies with paragraph (e) of this section shall be conducted.
(5) Employee notification. (i) Within five (5) working days after
the receipt of monitoring results, the employer shall notify each
employee in writing of the results which represent that employee's
exposures.
(ii) Whenever the results indicate that the representative employee
exposure exceeds the permissible exposure limit, the employer shall
include in the written notice a statement that the permissible exposure
limit was exceeded and a description of the corrective action taken to
reduce exposure to or below the permissible exposure limit.
(6) Accuracy of measurement. (i) The employer shall use a method of
monitoring and measurement which has an accuracy (with a confidence
level of 95 percent) of not less than plus or minus 25 percent for
concentrations of inorganic arsenic greater than or equal to 10
g/m3.
(ii) The employer shall use a method of monitoring and measurement
which has an accuracy (with confidence level of 95 percent) of not less
than plus or minus 35 percent for concentrations of inorganic arsenic
greater than 5 g/m3but less than 10 g/
m3.
(f) Regulated area--(1) Establishment. The employer shall establish
regulated areas where worker exposures to inorganic arsenic, without
regard to the use of respirators, are in excess of the permissible
limit.
(2) Demarcation. Regulated areas shall be demarcated and segregated
from the rest of the workplace in any manner that minimizes the number
of persons who will be exposed to inorganic arsenic.
(3) Access. Access to regulated areas shall be limited to authorized
persons or to persons otherwise authorized by the Act or regulations
issued pursuant thereto to enter such areas.
(4) Provision of respirators. All persons entering a regulated area
shall be supplied with a respirator, selected in accordance with
paragraph (h)(2) of this section.
(5) Prohibited activities. The employer shall assure that in
regulated areas, food or beverages are not consumed, smoking products,
chewing tobacco
[[Page 85]]
and gum are not used and cosmetics are not applied, except that these
activities may be conducted in the lunchrooms, change rooms and showers
required under paragraph (m) of this section. Drinking water may be
consumed in the regulated area.
(g) Methods of compliance--(1) Controls. (i) The employer shall
institute at the earliest possible time but not later than December 31,
1979, engineering and work practice controls to reduce exposures to or
below the permissible exposure limit, except to the extent that the
employer can establish that such controls are not feasible.
(ii) Where engineering and work practice controls are not sufficient
to reduce exposures to or below the permissible exposure limit, they
shall nonetheless be used to reduce exposures to the lowest levels
achievable by these controls and shall be supplemented by the use of
respirators in accordance with paragraph (h) of this section and other
necessary personal protective equipment. Employee rotation is not
required as a control strategy before respiratory protection is
instituted.
(2) Compliance Program. (i) The employer shall establish and
implement a written program to reduce exposures to or below the
permissible exposure limit by means of engineering and work practice
controls.
(ii) Written plans for these compliance programs shall include at
least the following:
(A) A description of each operation in which inorganic arsenic is
emitted; e.g. machinery used, material processed, controls in place,
crew size, operating procedures and maintenance practices;
(B) Engineering plans and studies used to determine methods selected
for controlling exposure to inorganic arsenic;
(C) A report of the technology considered in meeting the permissible
exposure limit;
(D) Monitoring data;
(E) A detailed schedule for implementation of the engineering
controls and work practices that cannot be implemented immediately and
for the adaption and implementation of any additional engineering and
work practices necessary to meet the permissible exposure limit;
(F) Whenever the employer will not achieve the permissible exposure
limit with engineering controls and work practices by December 31, 1979,
the employer shall include in the compliance plan an analysis of the
effectiveness of the various controls, shall install engineering
controls and institute work practices on the quickest schedule feasible,
and shall include in the compliance plan and implement a program to
minimize the discomfort and maximize the effectiveness of respirator
use; and
(G) Other relevant information.
(iii) Written plans for such a program shall be submitted upon
request to the Assistant Secretary and the Director, and shall be
available at the worksite for examination and copying by the Assistant
Secretary, Director, any affected employee or authorized employee
representatives.
(iv) The plans required by this paragraph shall be revised and
updated at least every 6 months to reflect the current status of the
program.
(h) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide
respirators that comply with the requirements of this paragraph.
Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
or work-practice controls.
(ii) Work operations, such as maintenance and repair activities, for
which the employer establishes that engineering and work-practice
controls are not feasible.
(iii) Work operations for which engineering and work-practice
controls are not yet sufficient to reduce employee exposures to or below
the permissible exposure limit.
(iv) Emergencies.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance with 29 CFR 1910.134 (b)
through (d) (except (d)(1)(iii)), and (f) through (m).
(ii) If an employee exhibits breathing difficulty during fit testing
or respirator use, they must be examined by a physician trained in
pulmonary medicine to determine whether they can use
[[Page 86]]
a respirator while performing the required duty.
(3) Respirator selection. (i) The employer must use Table I of this
section to select the appropriate respirator or combination of
respirators for inorganic arsenic compounds without significant vapor
pressure, and Table II of this section to select the appropriate
respirator or combination of respirators for inorganic arsenic compounds
that have significant vapor pressure.
(ii) When employee exposures exceed the permissible exposure limit
for inorganic arsenic and also exceed the relevant limit for other gases
(for example, sulfur dioxide), an air-purifying respirator provided to
the employee as specified by this section must have a combination high-
efficiency filter with an appropriate gas sorbent. (See footnote in
Table 1 of this section.)
(iii) Employees required to use respirators may choose, and the
employer must provide, a powered air-purifying respirator if it will
provide proper protection. In addition, the employer must provide a
combination dust and acid-gas respirator to employees who are exposed to
gases over the relevant exposure limits.
Table I--Respiratory Protection for Inorganic Arsenic Particulate Except
for Those With Significant Vapor Pressure
------------------------------------------------------------------------
Concentration of inorganic
arsenic (as As) or condition Required respirator
of use
------------------------------------------------------------------------
(i) Unknown or greater or (A) Any full facepiece self-contained
lesser than 20,000 g/m(3) (20 mg/m(3)) or pressure mode.
firefighting.
(ii) Not greater than 20,000 (A) Supplied air respirator with full
g/m(3) (20 mg/m(3)). facepiece, hood, or helmet or suit and
operated in positive pressure mode.
(iii) Not greater than 10,000 (A) Powered air-purifying respirators in
g/m(3) (10 mg/m(3)). all inlet face coverings with high
efficiency filters \1\.
(B)Half-mask supplied air respirators
operated in positive pressure mode.
(iv) Not greater than 500 (A) Full facepiece air-purifying
g/m(3). respirator equipped with high-efficiency
filter \1\.
(B) Any full facepiece supplied air
respirator.
(C) Any full facepiece self-contained
breathing apparatus.
(v) Not greater than 100 (A) Half-mask air-purifying respirator
g/m(3). equipped with high-efficiency filter
\1\.
(B) Any half-mask supplied air
respirator.
------------------------------------------------------------------------
\1\ High-efficiency filter-99.97 pct efficiency against 0.3 micrometer
monodisperse diethyl-hexyl phthalate (DOP) particles.
Table II--Respiratory Protection for Inorganic Arsenicals (Such as
Arsenic Trichloride \2\ and Arsenic Phosphide) With Significant Vapor
Pressure
------------------------------------------------------------------------
Concentration of inorganic
arsenic (as As) or condition Required respirator
of use
------------------------------------------------------------------------
(i) Unknown or greater or (A) Any full facepiece self-contained
lesser than 20,000 g/m(3) (20 mg/m(3)) or pressure mode.
firefighting.
(ii) Not greater than 20,000 (A) Supplied air respirator with full
g/m(3) (20 mg/m(3)). facepiece, hood, or helmet or suit and
operated in positive pressure mode.
(iii) Not greater than 10,000 (A) Half-mask \2\ supplied air respirator
g/m(3) (10 mg/m(3)). operated in positive pressure mode.
(iv) Not greater than 500 (A) Front or back mounted gas mask
g/m(3). equipped with high-efficiency filter \1\
and acid gas canister.
(B) Any full facepiece supplied air
respirator.
(C) Any full facepiece self-contained
breathing apparatus.
(v) Not greater than 100 (A) Half-mask air-purifying respirator
g/m(3). equipped with high efficiency filter \1\
and acid gas cartridge.
(B) Any half-mask supplied air
respirator.
------------------------------------------------------------------------
\1\ High-efficiency filter-99.97 pct efficiency against 0.3 micrometer
monodisperse diethyl-hexyl phthalate (DOP) particles.
\2\ Half-mask respirators shall not be used for protection against
arsenic trichloride, as it is rapidly absorbed through the skin.
(i) [Reserved]
(j) Protective work clothing and equipment--(1) Provision and use.
Where the possibility of skin or eye irritation from inorganic arsenic
exists, and for all workers working in regulated areas, the employer
shall provide at no cost
[[Page 87]]
to the employee and assure that employees use appropriate and clean
protective work clothing and equipment such as, but not limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, and shoes or coverlets;
(iii) Face shields or vented goggles when necessary to prevent eye
irritation, which comply with the requirements of Sec. 1910.133(a) (2)-
(6); and
(iv) Impervious clothing for employees subject to exposure to
arsenic trichloride.
(2) Cleaning and replacement. (i) The employer shall provide the
protective clothing required in paragraph (j) (1) of this section in a
freshly laundered and dry condition at least weekly, and daily if the
employee works in areas where exposures are over 100 g/
m3of inorganic arsenic or in areas where more frequent
washing is needed to prevent skin irritation.
(ii) The employer shall clean, launder, or dispose of protective
clothing required by paragraph (j) (1) of this section.
(iii) The employer shall repair or replace the protective clothing
and equipment as needed to maintain their effectiveness.
(iv) The employer shall assure that all protective clothing is
removed at the completion of a work shift only in change rooms
prescribed in paragraph (m) (1) of this section.
(v) The employer shall assure that contaminated protective clothing
which is to be cleaned, laundered, or disposed of, is placed in a closed
container in the change-room which prevents dispersion of inorganic
arsenic outside the container.
(vi) The employer shall inform in writing any person who cleans or
launders clothing required by this section, of the potentially harmful
effects including the carcinogenic effects of exposure to inorganic
arsenic.
(vii) The employer shall assure that the containers of contaminated
protective clothing and equipment in the workplace or which are to be
removed from the workplace are labelled as follows:
Caution: Clothing contaminated with inorganic arsenic; do not remove
dust by blowing or shaking. Dispose of inorganic arsenic contaminated
wash water in accordance with applicable local, State or Federal
regulations.
(viii) The employer shall prohibit the removal of inorganic arsenic
from protective clothing or equipment by blowing or shaking.
(k) Housekeeping--(1) Surfaces. All surfaces shall be maintained as
free as practicable of accumulations of inorganic arsenic.
(2) Cleaning floors. Floors and other accessible surfaces
contaminated with inorganic arsenic may not be cleaned by the use of
compressed air, and shoveling and brushing may be used only where
vacuuming or other relevant methods have been tried and found not to be
effective.
(3) Vacuuming. Where vacuuming methods are selected, the vacuums
shall be used and emptied in a manner to minimize the reentry of
inorganic arsenic into the workplace.
(4) Housekeeping plan. A written housekeeping and maintenance plan
shall be kept which shall list appropriate frequencies for carrying out
housekeeping operations, and for cleaning and maintaining dust
collection equipment. The plan shall be available for inspection by the
Assistant Secretary.
(5) Maintenance of equipment. Periodic cleaning of dust collection
and ventilation equipment and checks of their effectiveness shall be
carried out to maintain the effectiveness of the system and a notation
kept of the last check of effectiveness and cleaning or maintenance.
(l) [Reserved]
(m) Hygiene facilities and practices--(1) Change rooms. The employer
shall provide for employees working in regulated areas or subject to the
possibility of skin or eye irritation from inorganic arsenic, clean
change rooms equipped with storage facilities for street clothes and
separate storage facilities for protective clothing and equipment in
accordance with 29 CFR 1910.141(e).
(2) Showers. (i) The employer shall assure that employees working in
regulated areas or subject to the possibility of skin or eye irritation
from inorganic arsenic shower at the end of the work shift.
[[Page 88]]
(ii) The employer shall provide shower facilities in accordance with
Sec. 1910.141(d)(3).
(3) Lunchrooms. (i) The employer shall provide for employees working
in regulated areas, lunchroom facilities which have a temperature
controlled, positive pressure, filtered air supply, and which are
readily accessible to employees working in regulated areas.
(ii) The employer shall assure that employees working in the
regulated area or subject to the possibility of skin or eye irritation
from exposure to inorganic arsenic wash their hands and face prior to
eating.
(4) Lavatories. The employer shall provide lavatory facilities which
comply with Sec. 1910.141(d) (1) and (2).
(5) Vacuuming clothes. The employer shall provide facilities for
employees working in areas where exposure, without regard to the use of
respirators, exceeds 100 g/m3to vacuum their
protective clothing and clean or change shoes worn in such areas before
entering change rooms, lunchrooms or shower rooms required by paragraph
(j) of this section and shall assure that such employees use such
facilities.
(6) Avoidance of skin irritation. The employer shall assure that no
employee is exposed to skin or eye contact with arsenic trichloride, or
to skin or eye contact with liquid or particulate inorganic arsenic
which is likely to cause skin or eye irritation.
(n) Medical surveillance--(1) General--(i) Employees covered. The
employer shall institute a medical surveillance program for the
following employees:
(A) All employees who are or will be exposed above the action level,
without regard to the use of respirators, at least 30 days per year; and
(B) All employees who have been exposed above the action level,
without regard to respirator use, for 30 days or more per year for a
total of 10 years or more of combined employment with the employer or
predecessor employers prior to or after the effective date of this
standard. The determination of exposures prior to the effective date of
this standard shall be based upon prior exposure records, comparison
with the first measurements taken after the effective date of this
standard, or comparison with records of exposures in areas with similar
processes, extent of engineering controls utilized and materials used by
that employer.
(ii) Examination by physician. The employer shall assure that all
medical examinations and procedures are performed by or under the
supervision of a licensed physician, and shall be provided without cost
to the employee, without loss of pay and at a reasonable time and place.
(2) Initial examinations. By December 1, 1978, for employees
initially covered by the medical provisions of this section, or
thereafter at the time of initial assignment to an area where the
employee is likely to be exposed over the action level at least 30 days
per year, the employer shall provide each affected employee an
opportunity for a medical examination, including at least the following
elements:
(i) A work history and a medical history which shall include a
smoking history and the presence and degree of respiratory symptoms such
as breathlessness, cough, sputum production and wheezing.
(ii) A medical examination which shall include at least the
following:
(A) A 14" by 17" posterior-anterior chest X-ray and International
Labor Office UICC/Cincinnati (ILO U/C) rating;
(B) A nasal and skin examination; and
(C) Other examinations which the physician believes appropriate
because of the employees exposure to inorganic arsenic or because of
required respirator use.
(3) Periodic examinations. (i) The employer shall provide the
examinations specified in paragraphs (n)(2)(i) and (n)(2)(ii) at least
annually for covered employees who are under 45 years of age with fewer
than 10 years of exposure over the action level without regard to
respirator use.
(ii) The employer shall provide the examinations specified in
paragraphs (n)(2)(i) and (n)(2)(ii)(B) and (C) of this section at least
semiannually, and the x-ray requirement specified in paragraph
(n)(2)(ii)(A) of this section at least annually, for other covered
employees.
[[Page 89]]
(iii) Whenever a covered employee has not taken the examinations
specified in paragraphs (n)(2)(i) and (n)(2)(ii) of this section within
six (6) months preceding the termination of employment, the employer
shall provide such examinations to the employee upon termination of
employment.
(4) Additional examinations. If the employee for any reason develops
signs or symptoms commonly associated with exposure to inorganic arsenic
the employer shall provide an appropriate examination and emergency
medical treatment.
(5) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this standard and its appendices;
(ii) A description of the affected employee's duties as they relate
to the employee's exposure;
(iii) The employee's representative exposure level or anticipated
exposure level;
(iv) A description of any personal protective equipment used or to
be used; and
(v) Information from previous medical examinations of the affected
employee which is not readily available to the examining physician.
(6) Physician's written opinion. (i) The employer shall obtain a
written opinion from the examining physician which shall include:
(A) The results of the medical examination and tests performed;
(B) The physician's opinion as to whether the employee has any
detected medical conditions which would place the employee at increased
risk of material impairment of the employee's health from exposure to
inorganic arsenic;
(C) Any recommended limitations upon the employee's exposure to
inorganic arsenic or upon the use of protective clothing or equipment
such as respirators; and
(D) A statement that the employee has been informed by the physician
of the results of the medical examination and any medical conditions
which require further explanation or treatment.
(ii) The employer shall instruct the physician not to reveal in the
written opinion specific findings or diagnoses unrelated to occupational
exposure.
(iii) The employer shall provide a copy of the written opinion to
the affected employee.
(o) Employee information and training--(1) Training program. (i) The
employer shall institute a training program for all employees who are
subject to exposure to inorganic arsenic above the action level without
regard to respirator use, or for whom there is the possibility of skin
or eye irritation from inorganic arsenic. The employer shall assure that
those employees participate in the training program.
(ii) The training program shall be provided by October 1, 1978, for
employees covered by this provision, at the time of initial assignment
for those subsequently covered by this provision, and at least annually
for other covered employees thereafter; and the employer shall assure
that each employee is informed of the following:
(A) The information contained in Appendix A;
(B) The quantity, location, manner of use, storage, sources of
exposure, and the specific nature of operations which could result in
exposure to inorganic arsenic as well as any necessary protective steps;
(C) The purpose, proper use, and limitation of respirators;
(D) The purpose and a description of the medical surveillance
program as required by paragraph (n) of this section;
(E) The engineering controls and work practices associated with the
employee's job assignment; and
(F) A review of this standard.
(2) Access to training materials. (i) The employer shall make
readily available to all affected employees a copy of this standard and
its appendices.
(ii) The employer shall provide; upon request, all materials
relating to the employee information and training program to the
Assistant Secretary and the Director.
(p) Signs and labels--(1) General. (i) The employer may use labels
or signs required by other statutes, regulations, or ordinances in
addition to, or in combination with, signs and labels required by this
paragraph.
[[Page 90]]
(ii) The employer shall assure that no statement appears on or near
any sign or label required by this paragraph which contradicts or
detracts from the meaning of the required sign or label.
(2) Signs. (i) The employer shall post signs demarcating regulated
areas bearing the legend;
DANGER
INORGANIC ARSENIC
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
NO SMOKING OR EATING
RESPIRATOR REQUIRED
(ii) The employer shall assure that signs required by this paragraph
are illuminated and cleaned as necessary so that the legend is readily
visible.
(3) Labels. The employer shall apply precautionary labels to all
shipping and storage containers of inorganic arsenic, and to all
products containing inorganic arsenic except when the inorganic arsenic
in the product is bound in such a manner so as to make unlikely the
possibility of airborne exposure to inorganic arsenic. (Possible
examples of products not requiring labels are semiconductors, light
emitting diodes and glass). The label shall bear the following legend:
DANGER
CONTAINS INORGANIC ARSENIC
CANCER HAZARD
HARMFUL IF INHALED OR SWALLOWED
USE ONLY WITH ADEQUATE VENITLATION
OR RESPIRATORY PROTECTION
(q) Recordkeeping--(1) Exposure monitoring. (i) The employer shall
establish and maintain an accurate record of all monitoring required by
paragraph (e) of this section.
(ii) This record shall include:
(A) The date(s), number, duration location, and results of each of
the samples taken, including a description of the sampling procedure
used to determine representative employee exposure where applicable;
(B) A description of the sampling and analytical methods used and
evidence of their accuracy;
(C) The type of respiratory protective devices worn, if any;
(D) Name, social security number, and job classification of the
employees monitored and of all other employees whose exposure the
measurement is intended to represent; and
(E) The environmental variables that could affect the measurement of
the employee's exposure.
(iii) The employer shall maintain these monitoring records for at
least 40 years or for the duration of employment plus 20 years,
whichever, is longer.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance as required by paragraph (n) of this section.
(ii) This record shall include:
(A) The name, social security number, and description of duties of
the employee;
(B) A copy of the physician's written opinions;
(C) Results of any exposure monitoring done for that employee and
the representative exposure levels supplied to the physician; and
(D) Any employee medical complaints related to exposure to inorganic
arsenic.
(iii) The employer shall in addition keep, or assure that the
examining physician keeps, the following medical records;
(A) A copy of the medical examination results including medical and
work history required under paragraph (n) of this section;
(B) A description of the laboratory procedures and a copy of any
standards or guidelines used to interpret the test results or references
to that information;
(C) The initial X-ray;
(D) The X-rays for the most recent 5 years; and
(E) Any X-rays with a demonstrated abnormality and all subsequent X-
rays;
(iv) The employer shall maintain or assure that the physician
maintains those medical records for at least 40
[[Page 91]]
years, or for the duration of employment plus 20 years whichever is
longer.
(3) Availability. (i) The employer shall make available upon request
all records required to be maintained by paragraph (q) of this section
to the Assistant Secretary and the Director for examination and copying.
(ii) Records required by this paragraph shall be provided upon
request to employees, designated representatives, and the Assistant
Secretary in accordance with 29 CFR 1910.20 (a) through (e) and (g)
through (i).
(4) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by this section.
(ii) Whenever the employer ceases to do business and there is no
successor employer to receive and retain the records required to be
maintained by this section for the prescribed period, these records
shall be transmitted to the Director.
(iii) At the expiration of the retention period for the records
required to be maintained by this section, the employer shall notify the
Director at least 3 months prior to the disposal of such records and
shall transmit those records to the Director if he requests them within
that period.
(iv) The employer shall also comply with any additional requirements
involving the transfer of records set in 29 CFR 1910.20(h).
(r) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to inorganic arsenic conducted pursuant to paragraph (e) of
this section.
(2) Observation procedures. (i) Whenever observation of the
monitoring of employee exposure to inorganic arsenic requires entry into
an area where the use of respirators, protective clothing, or equipment
is required, the employer shall provide the observer with and assure the
use of such respirators, clothing, and such equipment, and shall require
the observer to comply with all other applicable safety and health
procedures.
(ii) Without interfering with the monitoring, observers shall be
entitled to;
(A) Receive an explanation of the measurement procedures;
(B) Observe all steps related to the monitoring of inorganic arsenic
performed at the place of exposure; and
(C) Record the results obtained or receive copies of the results
when returned by the laboratory.
(s) Effective date. This standard shall become effective August 1,
1978.
(t) Appendices. The information contained in the appendices to this
section is not intended by itself, to create any additional obligations
not otherwise imposed by this standard nor detract from any existing
obligation.
(u) Startup dates--(1) General. The startup dates of requirements of
this standard shall be the effective date of this standard unless
another startup date is provided for either in other paragraphs of this
section or in this paragraph.
(2) Monitoring. Initial monitoring shall be commenced on August 1,
1978, and shall be completed by September 15, 1978.
(3) Regulated areas. Regulated areas required to be established as a
result of initial monitoring shall be set up as soon as possible after
the results of that monitoring is known and no later than October 1,
1978.
(4) Compliance program. The written program required by paragraph
(g)(2) as a result of initial monitoring shall be made available for
inspection and copying as soon as possible and no later than December 1,
1978.
(5) Hygiene and lunchroom facilities. Construction plans for change-
rooms, showers, lavatories, and lunchroom facilities shall be completed
no later than December 1, 1978, and these facilities shall be
constructed and in use no later than July 1, 1979. However, if as part
of the compliance plan it is predicted by an independent engineering
firm that engineering controls and work practices will reduce exposures
below the permissible exposure limit by December 31, 1979, for affected
employees, then such facilities need not be completed until 1 year after
the engineering controls are completed or December 31, 1980, whichever
is earlier,
[[Page 92]]
if such controls have not in fact succeeded in reducing exposure to
below the permissible exposure limit.
(6) Summary of startup dates set forth elsewhere in this standard.
Startup Dates
August 1, 1978--Respirator use over 500 g/m3.
as soon as possible but no later than
September 15, 1978--Completion of initial monitoring.
October 1, 1978--Complete establishment of regulated areas. Respirator
use for employees exposed above 50 g/m3. Completion
of initial training. Notification of use.
December 1, 1978--Respirator use over 10 g/m3.
Completion of initial medical. Completion of compliance plan. Optional
use of powered air-purifying respirators.
July 1, 1979--Completion of lunch rooms and hygiene facilities.
December 31, 1979--Completion of engineering controls.
All other requirements of the standard have as their startup date August
1, 1978.
Appendix A to Sec. 1910.1018--Inorganic Arsenic Substance Information
Sheet
i. substance identification
A. Substance. Inorganic Arsenic.
B. Definition. Copper acetoarsenite, arsenic and all inorganic
compounds containing arsenic except arsine, measured as arsenic (As).
C. Permissible Exposure Limit. 10 micrograms per cubic meter of air
as determined as an average over an 8-hour period. No employee may be
exposed to any skin or eye contact with arsenic trichloride or to skin
or eye contact likely to cause skin or eye irritation.
D. Regulated Areas. Only employees authorized by your employer
should enter a regulated area.
ii. health hazard data
A. Comments. The health hazard of inorganic arsenic is high.
B. Ways in which the chemical affects your body. Exposure to
airborne concentrations of inorganic arsenic may cause lung cancer, and
can be a skin irritant. Inorganic arsenic may also affect your body if
swallowed. One compound in particular, arsenic trichloride, is
especially dangerous because it can be absorbed readily through the
skin. Because inorganic arsenic is a poison, you should wash your hands
thoroughly prior to eating or smoking.
iii. protective clothing and equipment
A. Respirators. Respirators will be provided by your employer at no
cost to you for routine use if your employer is in the process of
implementing engineering and work practice controls or where engineering
and work practice controls are not feasible or insufficient. You must
wear respirators for non-routine activities or in emergency situations
where you are likely to be exposed to levels of inorganic arsenic in
excess of the permissible exposure limit. Since how well your respirator
fits your face is very important, your employer is required to conduct
fit tests to make sure the respirator seals properly when you wear it.
These tests are simple and rapid and will be explained to you during
training sessions.
B. Protective clothing. If you work in a regulated area, your
employer is required to provide at no cost to you, and you must wear,
appropriate, clean, protective clothing and equipment. The purpose of
this equipment is to prevent you from bringing to your home arsenic-
contaminated dust and to protect your body from repeated skin contact
with inorganic arsenic likely to cause skin irritation. This clothing
should include such items as coveralls or similar full-body clothing,
gloves, shoes or coverlets, and aprons. Protective equipment should
include face shields or vented goggles, where eye irritation may occur.
y
iv. hygiene facilities and practices
You must not eat, drink, smoke, chew gum or tobacco, or apply
cosmetics in the regulated area, except that drinking water is
permitted. If you work in a regulated area your employer is required to
provide lunchrooms and other areas for these purposes.
If you work in a regulated area, your employer is required to
provide showers, washing facilities, and change rooms. You must wash
your face, and hands before eating and must shower at the end of the
work shift. Do not take used protective clothing out of change rooms
without your employer's permission. Your employer is required to provide
for laundering or cleaning of your protective clothing.
v. signs and labels
Your employer is required to post warning signs and labels for your
protection. Signs must be posted in regulated areas. The signs must warn
that a cancer hazard is present, that only authorized employees may
enter the area, and that no smoking or eating is allowed, and that
respirators must be worn.
vi. medical examinations
If your exposure to arsenic is over the Action Level (5 mg/m3)--
(including all persons working in regulated areas) at least 30 days per
year, or you have been exposed to arsenic
[[Page 93]]
for more than 10 years over the Action Level, your employer is required
to provide you with a medical examination. The examination shall be
every 6 months for employees over 45 years old or with more than 10
years exposure over the Action Level and annually for other covered
employees. The medical examination must include a medical history; a
chest x-ray; a skin examination and a nasal examination. The examining
physician will provide a written opinion to your employer containing the
results of your medical exams. You should also receive a copy of this
opinion. The physician must not tell your employer any conditions he
detects unrelated to occupational exposure to arsenic but must tell you
those conditions.
vii. observation of monitoring
Your employer is required to monitor your exposure to arsenic and
you or your representatives are entitled to observe the monitoring
procedure. You are entitled to receive an explanation of the measurement
procedure, and to record the results obtained. When the monitoring
procedure is taking place in an area where respirators or personal
protective clothing and equipment are required to be worn, you must also
be provided with and must wear the protective clothing and equipment.
viii. access to records
You or your representative are entitled to records of your exposure
to inorganic arsenic and your medical examination records if you request
your employer to provide them.
ix. training and notification
Additional information on all of these items plus training as to
hazards of exposure to inorganic arsenic and the engineering and work
practice controls associated with your job will also be provided by your
employer. If you are exposed over the permissible exposure limit, your
employer must inform you of that fact and the actions he is taking to
reduce your exposures.
Appendix B to Sec. 1910.1018--Substance Technical Guidelines
arsenic, arsenic trioxide, arsenic trichloride (three examples)
I. Physical and chemical properties
A. Arsenic (metal).
1. Formula: As.
2. Appearance: Gray metal.
3. Melting point: Sublimes without melting at 613C.
4. Specific Gravity: (H20=1):5.73.
5. Solubility in water: Insoluble.
B. Arsenic Trioxide.
1. Formula: As203, (As406).
2. Appearance: White powder.
3. Melting point: 315C.
4. Specific Gravity (H20=1):3.74.
5. Solubility in water: 3.7 grams in 100cc of water at 20c.
C. Arsenic Trichloride (liquid).
1. Formula: AsC13.
2. Appearance: Colorless or pale yellow liquid.
3. Melting point: -8.5C.
4. Boiling point: 130.2C.
5. Specific Gravity (H20=1):2.16 at 20C.
6. Vapor Pressure: 10mm Hg at 23.5C.
7. Solubility in Water: Decomposes in water.
II. Fire, explosion and reactivity data.
A. Fire: Arsenic, arsenic Trioxide and Arsenic Trichloride are
nonflammable.
B. Reactivity:
1. Conditions Contributing to instability: Heat.
2. Incompatibility: Hydrogen gas can react with inorganic arsenic to
form the highly toxic gas arsine.
III. Monitoring and Measurement Procedures
Samples collected should be full shift (at least 7-hour) samples.
Sampling should be done using a personal sampling pump at a flow rate of
2 liters per minute. Samples should be collected on 0.8 micrometer pore
size membrane filter (37mm diameter). Volatile arsenicals such as
arsenic trichloride can be most easily collected in a midget bubbler
filled with 15 ml. of 0.1 N NaOH.
The method of sampling and analysis should have an accuracy of not
less than 25 percent (with a confidence limit of 95 percent)
for 10 micrograms per cubic meter of air (10 g/m3)
and 35 percent (with a confidence limit of 95 percent) for
concentrations of inorganic arsenic between 5 and 10 g/
m3.
Appendix C to Sec. 1910.1018--Medical Surveillance Guidelines
I. General
Medical examinations are to be provided for all employees exposed to
levels of inorganic arsenic above the action level (5 g/
m3) for at least 30 days per year (which would include among
others, all employees, who work in regulated areas). Examinations are
also to be provided to all employees who have had 10 years or more
exposure above the action level for more than 30 days per year while
working for the present or predecessor employer though they may no
longer be exposed above the level.
An initial medical examination is to be provided to all such
employees by December 1, 1978. In addition, an initial medical
examination is to be provided to all employees who are first assigned to
areas in which worker exposure will probably exceed 5 g/
[[Page 94]]
m3(after the effective date of this standard) at the time of
initial assignment. In addition to its immediate diagnostic usefulness,
the initial examination will provide a baseline for comparing future
test results. The initial examination must include as a minimum the
following elements:
(1) A work and medical history, including a smoking history, and
presence and degree of respiratory symptoms such as breathlessness,
cough, sputum production, and wheezing;
(2) A 14" by 17" posterior-anterior chest X-ray and an International
Labor Office UICC/Cincinnati (ILO U/C) rating;
(3) A nasal and skin examination; and
(4) Other examinations which the physician believes appropriate
because of the employee's exposure to inorganic arsenic or because of
required respirator use.
Periodic examinations are also to be provided to the employees
listed above. The periodic examinations shall be given annually for
those covered employees 45 years of age or less with fewer than 10 years
employment in areas where employee exposure exceeds the action level (5
g/m3). Periodic examinations need not include sputum
cytology and only an updated medical history is required.
Periodic examinations for other covered employees, shall be provided
every six (6) months. These examinations shall include all tests
required in the initial examination, except that the medical history
need only be updated.
The examination contents are minimum requirements. Additional tests
such as lateral and oblique X-rays or pulmonary function tests may be
useful. For workers exposed to three arsenicals which are associated
with lymphatic cancer, copper acetoarsenite, potassium arsenite, or
sodium arsenite the examination should also include palpation of
superficial lymph nodes and complete blood count.
ii. noncarcinogenic effects
The OSHA standard is based on minimizing risk of exposed workers
dying of lung cancer from exposure to inorganic arsenic. It will also
minimize skin cancer from such exposures.
The following three sections quoted from ``Occupational Diseases: A
Guide to Their Recognition'', Revised Edition, June 1977, National
Institute for Occupational Safety and Health is included to provide
information on the nonneoplastic effects of exposure to inorganic
arsenic. Such effects should not occur if the OSHA standards are
followed.
A. Local-- Trivalent arsenic compounds are corrosive to the skin.
Brief contact has no effect but prolonged contact results in a local
hyperemia and later vesicular or pustular eruption. The moist mucous
membranes are most sensitive to the irritant action. Conjunctiva, moist
and macerated areas of skin, the eyelids, the angles of the ears, nose,
mouth, and respiratory mucosa are also vulnerable to the irritant
effects. The wrists are common sites of dermatitis, as are the genitalia
if personal hygiene is poor. Perforations of the nasal septum may occur.
Arsenic trioxide and pentoxide are capable of producing skin
sensitization and contact dermatitis. Arsenic is also capable of
producing keratoses, especially of the palms and soles.
B. Systemic-- The acute toxic effects of arsenic are generally seen
following ingestion of inorganic arsenical compounds. This rarely occurs
in an industrial setting. Symptoms develop within \1/2\ to 4 hours
following ingestion and are usually characterized by constriction of the
throat followed by dysphagia, epigastric pain, vomiting, and watery
diarrhea. Blood may appear in vomitus and stools. If the amount ingested
is sufficiently high, shock may develop due to severe fluid loss, and
death may ensue in 24 hours. If the acute effects are survived,
exfoliative dermatitis and peripheral neuritis may develop.
Cases of acute arsenical poisoning due to inhalation are exceedingly
rare in industry. When it does occur, respiratory tract symptoms--cough,
chest pain, dyspnea--giddiness, headache, and extreme general weakness
precede gastrointestinal symptoms. The acute toxic symptoms of trivalent
arsenical poisoning are due to severe inflammation of the mucous
membranes and greatly increased permeability of the blood capillaries.
Chronic arsenical poisoning due to ingestion is rare and generally
confined to patients taking prescribed medications. However, it can be a
concomitant of inhaled inorganic arsenic from swallowed sputum and
improper eating habits. Symptoms are weight loss, nausea and diarrhea
alternating with constipation, pigmentation and eruption of the skin,
loss of hair, and peripheral neuritis. Chronic hepatitis and cirrhosis
have been described. Polyneuritis may be the salient feature, but more
frequently there are numbness and parasthenias of ``glove and stocking''
distribution. The skin lesions are usually melanotic and keratotic and
may occasionally take the form of an intradermal cancer of the squamous
cell type, but without infiltrative properties. Horizontal white lines
(striations) on the fingernails and toenails are commonly seen in
chronic arsenical poisoning and are considered to be a diagnostic
accompaniment of arsenical polyneuritis.
Inhalation of inorganic arsenic compounds is the most common cause
of chronic poisoning in the industrial situation. This condition is
divided into three phases based on signs and symptoms.
[[Page 95]]
First Phase: The worker complains of weakness, loss of appetite,
some nausea, occasional vomiting, a sense of heaviness in the stomach,
and some diarrhea.
Second Phase: The worker complains of conjunctivitis, a catarrhal
state of the mucous membranes of the nose, larynx, and respiratory
passage. Coryza, hoarseness, and mild tracheobronchitis may occur.
Perforation of the nasal septum is common, and is probably the most
typical lesion of the upper respiratory tract in occupational exposure
to arsenical dust. Skin lesions, eczematoid and allergic in type, are
common.
Third Phase: The worker complains of symptoms of peripheral
neuritis, initially of hands and feet, which is essentially sensory. In
more severe cases, motor paralyses occur; the first muscles affected are
usually the toe extensors and the peronei. In only the most severe cases
will paralysis of flexor muscles of the feet or of the extensor muscles
of hands occur.
Liver damage from chronic arsenical poisoning is still debated, and
as yet the question is unanswered. In cases of chronic and acute
arsenical poisoning, toxic effects to the myocardium have been reported
based on EKG changes. These findings, however, are now largely
discounted and the EKG changes are ascribed to electrolyte disturbances
concomitant with arsenicalism. Inhalation of arsenic trioxide and other
inorganic arsenical dusts does not give rise to radiological evidence or
pneumoconiosis. Arsenic does have a depressant effect upon the bone
marrow, with disturbances of both erythropoiesis and myelopoiesis.
Bibliography
Dinman, B. D. 1960. Arsenic; chronic human intoxication. J. Occup.
Med. 2:137.
Elkins, H. B. 1959. The Chemistry of Industrial Toxicology, 2nd ed.
John Wiley and Sons, New York.
Holmquist, L. 1951. Occupational arsenical dermatitis; a study among
employees at a copper-ore smelting works including investigations of
skin reactions to contact with arsenic compounds. Acta. Derm. Venereol.
(Supp. 26) 31:1.
Pinto, S. S., and C. M. McGill. 1953. Arsenic trioxide exposure in
industry. Ind. Med. Surg. 22:281.
Pinto, S. S., and K. W. Nelson. 1976. Arsenic toxicology and
industrial exposure. Annu. Rev. Pharmacol. Toxicol. 16:95.
Vallee, B. L., D. D. Ulmer, and W. E. C. Wacker. 1960. Arsenic
toxicology and biochemistry. AMA Arch. Indust. Health 21:132.
[39 FR 23502, June 27, 1974, as amended at 43 FR 19624, May 5, 1978; 43
FR 28472, June 30, 1978; 45 FR 35282, May 23, 1980; 54 FR 24334, June 7,
1989; 58 FR 35310, June 30, 1993; 61 FR 5508, Feb. 13, 1996; 61 FR 9245,
Mar. 7, 1996; 63 FR 1286, Jan. 8, 1998; 63 FR 33468, June 18, 1998]
Sec. 1910.1020 Access to employee exposure and medical records.
(a) Purpose. The purpose of this section is to provide employees and
their designated representatives a right of access to relevant exposure
and medical records; and to provide representatives of the Assistant
Secretary a right of access to these records in order to fulfill
responsibilities under the Occupational Safety and Health Act. Access by
employees, their representatives, and the Assistant Secretary is
necessary to yield both direct and indirect improvements in the
detection, treatment, and prevention of occupational disease. Each
employer is responsible for assuring compliance with this section, but
the activities involved in complying with the access to medical records
provisions can be carried out, on behalf of the employer, by the
physician or other health care personnel in charge of employee medical
records. Except as expressly provided, nothing in this section is
intended to affect existing legal and ethical obligations concerning the
maintenance and confidentiality of employee medical information, the
duty to disclose information to a patient/employee or any other aspect
of the medical-care relationship, or affect existing legal obligations
concerning the protection of trade secret information.
(b) Scope and application. (1) This section applies to each general
industry, maritime, and construction employer who makes, maintains,
contracts for, or has access to employee exposure or medical records, or
analyses thereof, pertaining to employees exposed to toxic substances or
harmful physical agents.
[[Page 96]]
(2) This section applies to all employee exposure and medical
records, and analyses thereof, of such employees, whether or not the
records are mandated by specific occupational safety and health
standards.
(3) This section applies to all employee exposure and medical
records, and analyses thereof, made or maintained in any manner,
including on an in-house of contractual (e.g., fee-for-service) basis.
Each employer shall assure that the preservation and access requirements
of this section are complied with regardless of the manner in which the
records are made or maintained.
(c) Definitions. (1) Access means the right and opportunity to
examine and copy.
(2) Analysis using exposure or medical records means any compilation
of data or any statistical study based at least in part on information
collected from individual employee exposure or medical records or
information collected from health insurance claims records, provided
that either the analysis has been reported to the employer or no further
work is currently being done by the person responsible for preparing the
analysis.
(3) Designated representative means any individual or organization
to whom an employee gives written authorization to exercise a right of
access. For the purposes of access to employee exposure records and
analyses using exposure or medical records, a recognized or certified
collective bargaining agent shall be treated automatically as a
designated representative without regard to written employee
authorization.
(4) Employee means a current employee, a former employee, or an
employee being assigned or transferred to work where there will be
exposure to toxic substances or harmful physical agents. In the case of
a deceased or legally incapacitated employee, the employee's legal
representative may directly exercise all the employee's rights under
this section.
(5) Employee exposure record means a record containing any of the
following kinds of information:
(i) Environmental (workplace) monitoring or measuring of a toxic
substance or harmful physical agent, including personal, area, grab,
wipe, or other form of sampling, as well as related collection and
analytical methodologies, calculations, and other background data
relevant to interpretation of the results obtained;
(ii) Biological monitoring results which directly assess the
absorption of a toxic substance or harmful physical agent by body
systems (e.g., the level of a chemical in the blood, urine, breath,
hair, fingernails, etc) but not including results which assess the
biological effect of a substance or agent or which assess an employee's
use of alcohol or drugs;
(iii) Material safety data sheets indicating that the material may
pose a hazard to human health; or
(iv) In the absence of the above, a chemcial inventory or any other
record which reveals where and when used and the identity (e.g.,
chemical, common, or trade name) of a toxic substance or harmful
physical agent.
(6)(i) Employee medical record means a record concerning the health
status of an employee which is made or maintained by a physician, nurse,
or other health care personnel or technician, including:
(A) Medical and employment questionnaires or histories (including
job description and occupational exposures),
(B) The results of medical examinations (pre-employment, pre-
assignment, periodic, or episodic) and laboratory tests (including chest
and other X-ray examinations taken for the purposes of establishing a
base-line or detecting occupational illness, and all biological
monitoring not defined as an ``employee exposure record''),
(C) Medical opinions, diagnoses, progress notes, and
recommendations,
(D) First aid records,
(E) Descriptions of treatments and prescriptions, and
(F) Employee medical complaints.
(ii) ``Employee medical record'' does not include medical
information in the form of:
(A) Physical specimens (e.g., blood or urine samples) which are
routinely discarded as a part of normal medical practice; or
[[Page 97]]
(B) Records concerning health insurance claims if maintained
separately from the employer's medical program and its records, and not
accessible to the employer by employee name or other direct personal
identifier (e.g., social security number, payroll number, etc.); or
(C) Records created solely in preparation for litigation which are
privileged from discovery under the applicable rules of procedure or
evidence; or
(D) Records concerning voluntary employee assistance programs
(alcohol, drug abuse, or personal counseling programs) if maintained
separately from the employer's medical program and its records.
(7) Employer means a current employer, a former employer, or a
successor employer.
(8) Exposure or exposed means that an employee is subjected to a
toxic substance or harmful physical agent in the course of employment
through any route of entry (inhalation, ingestion, skin contact or
absorption, etc.), and includes past exposure and potential (e.g.,
accidental or possible) exposure, but does not include situations where
the employer can demonstrate that the toxic substance or harmful
physical agent is not used, handled, stored, generated, or present in
the workplace in any manner different from typical non-occupational
situations.
(9) Health Professional means a physician, occupational health
nurse, industrial hygienist, toxicologist, or epidemiologist, providing
medical or other occupational health services to exposed employees.
(10) Record means any item, collection, or grouping of information
regardless of the form or process by which it is maintained (e.g., paper
document, microfiche, microfilm, X-ray film, or automated data
processing).
(11) Specific chemical identity means the chemical name, Chemical
Abstracts Service (CAS) Registry Number, or any other information that
reveals the precise chemical designation of the substance.
(12)(i) Specific written consent means a written authorization
containing the following:
(A) The name and signature of the employee authorizing the release
of medical information,
(B) The date of the written authorization,
(C) The name of the individual or organization that is authorized to
release the medical information,
(D) The name of the designated representative (individual or
organization) that is authorized to receive the released information,
(E) A general description of the medical information that is
authorized to be released,
(F) A general description of the purpose for the release of the
medical information, and
(G) A date or condition upon which the written authorization will
expire (if less than one year).
(ii) A written authorization does not operate to authorize the
release of medical information not in existence on the date of written
authorization, unless the release of future information is expressly
authorized, and does not operate for more than one year from the date of
written authorization.
(iii) A written authorization may be revoked in writing
prospectively at any time.
(13) Toxic substance or harmful physical agent means any chemical
substance, biological agent (bacteria, virus, fungus, etc.), or physical
stress (noise, heat, cold, vibration, repetitive motion, ionizing and
non-ionizing radiation, hypo-or hyperbaric pressure, etc.) which:
(i) Is listed in the latest printed edition of the National
Institute for Occupational Safety and Health (NIOSH) Registry of Toxic
Effects of Chemical Substances (RTECS), which is incorporated by
reference as specified in Sec. 1910.6; or
(ii) Has yielded positive evidence of an acute or chronic health
hazard in testing conducted by, or known to, the employer; or
(iii) Is the subject of a material safety data sheet kept by or
known to the employer indicating that the material may pose a hazard to
human health.
(14) Trade secret means any confidential formula, pattern, process,
device, or information or compilation of information that is used in an
employer's
[[Page 98]]
business and that gives the employer an opportunity to obtain an
advantage over competitors who do not know or use it.
(d) Preservation of records. (1) Unless a specific occupational
safety and health standard provides a different period of time, each
employer shall assure the preservation and retention of records as
follows:
(i) Employee medical records. The medical record for each employee
shall be preserved and maintained for at least the duration of
employment plus thirty (30) years, except that the following types of
records need not be retained for any specified period:
(A) Health insurance claims records maintained separately from the
employer's medical program and its records,
(B) First aid records (not including medical histories) of one-time
treatment and subsequent observation of minor scratches, cuts, burns,
splinters, and the like which do not involve medical treatment, loss of
consciousness, restriction of work or motion, or transfer to another
job, if made on-site by a non-physician and if maintained separately
from the employer's medical program and its records, and
(C) The medical records of employees who have worked for less than
(1) year for the employer need not be retained beyond the term of
employment if they are provided to the employee upon the termination of
employment.
(ii) Employee exposure records. Each employee exposure record shall
be preserved and maintained for at least thirty (30) years, except that:
(A) Background data to environmental (workplace) monitoring or
measuring, such as laboratory reports and worksheets, need only be
retained for one (1) year as long as the sampling results, the
collection methodology (sampling plan), a description of the analytical
and mathematical methods used, and a summary of other background data
relevant to interpretation of the results obtained, are retained for at
least thirty (30) years; and
(B) Material safety data sheets and paragraph (c)(5)(iv) records
concerning the identity of a substance or agent need not be retained for
any specified period as long as some record of the identity (chemical
name if known) of the substance or agent, where it was used, and when it
was used is retained for at least thirty (30) years;\1\ and
---------------------------------------------------------------------------
\1\ Material safety data sheets must be kept for those chemicals
currently in use that are effected by the Hazard Communication Standard
in accordance with 29 CFR 1910.1200(g).
---------------------------------------------------------------------------
(C) Biological monitoring results designated as exposure records by
specific occupational safety and health standards shall be preserved and
maintained as required by the specific standard.
(iii) Analyses using exposure or medical records. Each analysis
using exposure or medial records shall be preserved and maintained for
at least thirty (30) years.
(2) Nothing in this section is intended to mandate the form, manner,
or process by which an employer preserves a record as long as the
information contained in the record is preserved and retrievable, except
that chest X-ray films shall be preserved in their original state.
(e) Access to records--(1) General. (i) Whenever an employee or
designated representative requests access to a record, the employer
shall assure that access is provided in a reasonable time, place, and
manner. If the employer cannot reasonably provide access to the record
within fifteen (15) working days, the employer shall within the fifteen
(15) working days apprise the employee or designated representative
requesting the record of the reason for the delay and the earliest date
when the record can be made available.
(ii) The employer may require of the requester only such information
as should be readily known to the requester and which may be necessary
to locate or identify the records being requested (e.g. dates and
locations where the employee worked during the time period in question).
(iii) Whenever an employee or designated representative requests a
copy of a record, the employer shall assure that either:
(A) A copy of the record is provided without cost to the employee or
representative,
(B) The necessary mechanical copying facilities (e.g., photocopying)
are
[[Page 99]]
made available without cost to the employee or representative for
copying the record, or
(C) The record is loaned to the employee or representative for a
reasonable time to enable a copy to be made.
(iv) In the case of an original X-ray, the employer may restrict
access to on-site examination or make other suitable arrangements for
the temporary loan of the X-ray.
(v) Whenever a record has been previously provided without cost to
an employee or designated representative, the employer may charge
reasonable, non-discriminatory administrative costs (i.e., search and
copying expenses but not including overhead expenses) for a request by
the employee or designated representative for additional copies of the
record, except that
(A) An employer shall not charge for an initial request for a copy
of new information that has been added to a record which was previously
provided; and
(B) An employer shall not charge for an initial request by a
recognized or certified collective bargaining agent for a copy of an
employee exposure record or an analysis using exposure or medical
records.
(vi) Nothing in this section is intended to preclude employees and
collective bargaining agents from collectively bargaining to obtain
access to information in addition to that available under this section.
(2) Employee and designated representative access--(i) Employee
exposure records. (A) Except as limited by paragraph (f) of this
section, each employer shall, upon request, assure the access to each
employee and designated representative to employee exposure records
relevant to the employee. For the purpose of this section, an exposure
record relevant to the employee consists of:
(1) A record which measures or monitors the amount of a toxic
substance or harmful physical agent to which the employee is or has been
exposed;
(2) In the absence of such directly relevant records, such records
of other employees with past or present job duties or working conditions
related to or similar to those of the employee to the extent necessary
to reasonably indicate the amount and nature of the toxic substances or
harmful physical agents to which the employee is or has been subjected,
and
(3) Exposure records to the extent necessary to reasonably indicate
the amount and nature of the toxic substances or harmful physical agents
at workplaces or under working conditions to which the employee is being
assigned or transferred.
(B) Requests by designated representatives for unconsented access to
employee exposure records shall be in writing and shall specify with
reasonable particularity:
(1) The records requested to be disclosed; and
(2) The occupational health need for gaining access to these
records.
(ii) Employee medical records. (A) Each employer shall, upon
request, assure the access of each employee to employee medical records
of which the employee is the subject, except as provided in paragraph
(e)(2)(ii)(D) of this section.
(B) Each employer shall, upon request, assure the access of each
designated representative to the employee medical records of any
employee who has given the designated representative specific written
consent. Appendix A to this section contains a sample form which may be
used to establish specific written consent for access to employee
medical records.
(C) Whenever access to employee medical records is requested, a
physician representing the employer may recommend that the employee or
designated representative:
(1) Consult with the physician for the purposes of reviewing and
discussing the records requested,
(2) Accept a summary of material facts and opinions in lieu of the
records requested, or
(3) Accept release of the requested records only to a physician or
other designated representative.
(D) Whenever an employee requests access to his or her employee
medical records, and a physician representing the employer believes that
direct employee access to information contained in the records regarding
a specific diagnosis of a terminal illness or a psychiatric condition
could be detrimental
[[Page 100]]
to the employee's health, the employer may inform the employee that
access will only be provided to a designated representative of the
employee having specific written consent, and deny the employee's
request for direct access to this information only. Where a designated
representative with specific written consent requests access to
information so withheld, the employer shall assure the access of the
designated representative to this information, even when it is known
that the designated representative will give the information to the
employee.
(E) A physician, nurse, or other responsible health care personnel
maintaining medical records may delete from requested medical records
the identity of a family member, personal friend, or fellow employee who
has provided confidential information concerning an employee's health
status.
(iii) Analyses using exposure or medical records. (A) Each employee
shall, upon request, assure the access of each employee and designated
representative to each analysis using exposure or medical records
concerning the employee's working conditions or workplace.
(B) Whenever access is requested to an analysis which reports the
contents of employee medical records by either direct identifier (name,
address, social security number, payroll number, etc.) or by information
which could reasonably be used under the circumstances indirectly to
identify specific employees (exact age, height, weight, race, sex, date
of initial employment, job title, etc.), the employer shall assure that
personal identifiers are removed before access is provided. If the
employer can demonstrate that removal of personal identifiers from an
analysis is not feasible, access to the personally identifiable portions
of the analysis need not be provided.
(3) OSHA access. (i) Each employer shall, upon request, and without
derogation of any rights under the Constitution or the Occupational
Safety and Health Act of 1970, 29 U.S.C. 651 et seq., that the employer
chooses to exercise, assure the prompt access of representatives of the
Assistant Secretary of Labor for Occupational Safety and Health to
employee exposure and medical records and to analyses using exposure or
medical records. Rules of agency practice and procedure governing OSHA
access to employee medical records are contained in 29 CFR 1913.10.
(ii) Whenever OSHA seeks access to personally identifiable employee
medical information by presenting to the employer a written access order
pursuant to 29 CFR 1913.10(d), the employer shall prominently post a
copy of the written access order and its accompanying cover letter for
at least fifteen (15) working days.
(f) Trade secrets. (1) Except as provided in paragraph (f)(2) of
this section, nothing in this section precludes an employer from
deleting from records requested by a health professional, employee, or
designated representative any trade secret data which discloses
manufacturing processes, or discloses the percentage of a chemical
substance in mixture, as long as the health professional, employee, or
designated representative is notified that information has been deleted.
Whenever deletion of trade secret information substantially impairs
evaluation of the place where or the time when exposure to a toxic
substance or harmful physical agent occurred, the employer shall provide
alternative information which is sufficient to permit the requesting
party to identify where and when exposure occurred.
(2) The employer may withhold the specific chemical identity,
including the chemical name and other specific identification of a toxic
substance from a disclosable record provided that:
(i) The claim that the information withheld is a trade secret can be
supported;
(ii) All other available information on the properties and effects
of the toxic substance is disclosed;
(iii) The employer informs the requesting party that the specific
chemical identity is being withheld as a trade secret; and
(iv) The specific chemical identity is made available to health
professionals, employees and designated representatives in accordance
with the specific applicable provisions of this paragraph.
(3) Where a treating physician or nurse determines that a medical
emergency exists and the specific chemical
[[Page 101]]
identity of a toxic substance is necessary for emergency or first-aid
treatment, the employer shall immediately disclose the specific chemical
identity of a trade secret chemical to the treating physician or nurse,
regardless of the existence of a written statement of need or a
confidentiality agreement. The employer may require a written statement
of need and confidentiality agreement, in accordance with the provisions
of paragraphs (f)(4) and (f)(5), as soon as circumstances permit.
(4) In non-emergency situations, an employer shall, upon request,
disclose a specific chemical identity, otherwise permitted to be
withheld under paragraph (f)(2) of this section, to a health
professional, employee, or designated representative if:
(i) The request is in writing;
(ii) The request describes with reasonable detail one or more of the
following occupational health needs for the information:
(A) To assess the hazards of the chemicals to which employees will
be exposed;
(B) To conduct or assess sampling of the workplace atmosphere to
determine employee exposure levels;
(C) To conduct pre-assignment or periodic medical surveillance of
exposed employees;
(D) To provide medical treatment to exposed employees;
(E) To select or assess appropriate personal protective equipment
for exposed employees;
(F) To design or assess engineering controls or other protective
measures for exposed employees; and
(G) To conduct studies to determine the health effects of exposure.
(iii) The request explains in detail why the disclosure of the
specific chemical identity is essential and that, in lieu thereof, the
disclosure of the following information would not enable the health
professional, employee or designated representative to provide the
occupational health services described in paragraph (f)(4)(ii) of this
section:
(A) The properties and effects of the chemical;
(B) Measures for controlling workers' exposure to the chemical;
(C) Methods of monitoring and analyzing worker exposure to the
chemical; and,
(D) Methods of diagnosing and treating harmful exposures to the
chemical;
(iv) The request includes a description of the procedures to be used
to maintain the confidentiality of the disclosed information; and,
(v) The health professional, employee, or designated representative
and the employer or contractor of the services of the health
professional or designated representative agree in a written
confidentiality agreement that the health professional, employee or
designated representative will not use the trade secret information for
any purpose other than the health need(s) asserted and agree not to
release the information under any circumstances other than to OSHA, as
provided in paragraph (f)(9) of this section, except as authorized by
the terms of the agreement or by the employer.
(5) The confidentiality agreement authorized by paragraph (f)(4)(iv)
of this section:
(i) May restrict the use of the information to the health purposes
indicated in the written statement of need;
(ii) May provide for appropriate legal remedies in the event of a
breach of the agreement, including stipulation of a reasonable pre-
estimate of likely damages; and,
(iii) May not include requirements for the posting of a penalty
bond.
(6) Nothing in this section is meant to preclude the parties from
pursuing non-contractual remedies to the extent permitted by law.
(7) If the health professional, employee or designated
representative receiving the trade secret information decides that there
is a need to disclose it to OSHA, the employer who provided the
information shall be informed by the health professional prior to, or at
the same time as, such disclosure.
(8) If the employer denies a written request for disclosure of a
specific chemical identity, the denial must:
(i) Be provided to the health professional, employee or designated
representative within thirty days of the request;
(ii) Be in writing;
[[Page 102]]
(iii) Include evidence to support the claim that the specific
chemical identity is a trade secret;
(iv) State the specific reasons why the request is being denied;
and,
(v) Explain in detail how alternative information may satisfy the
specific medical or occupational health need without revealing the
specific chemical identity.
(9) The health professional, employee, or designated representative
whose request for information is denied under paragraph (f)(4) of this
section may refer the request and the written denial of the request to
OSHA for consideration.
(10) When a heath professional employee, or designated
representative refers a denial to OSHA under paragraph (f)(9) of this
section, OSHA shall consider the evidence to determine if:
(i) The employer has supported the claim that the specific chemical
identity is a trade secret;
(ii) The health professional employee, or designated representative
has supported the claim that there is a medical or occupational health
need for the information; and
(iii) The health professional, employee or designated representative
has demonstrated adequate means to protect the confidentiality.
(11)(i) If OSHA determines that the specific chemical identity
requested under paragraph (f)(4) of this section is not a bona fide
trade secret, or that it is a trade secret but the requesting health
professional, employee or designated representatives has a legitimate
medical or occupational health need for the information, has executed a
written confidentiality agreement, and has shown adequate means for
complying with the terms of such agreement, the employer will be subject
to citation by OSHA.
(ii) If an employer demonstrates to OSHA that the execution of a
confidentiality agreement would not provide sufficient protection
against the potential harm from the unauthorized disclosure of a trade
secret specific chemical identity, the Assistant Secretary may issue
such orders or impose such additional limitations or conditions upon the
disclosure of the requested chemical information as may be appropriate
to assure that the occupational health needs are met without an undue
risk of harm to the employer.
(12) Notwithstanding the existence of a trade secret claim, an
employer shall, upon request, disclose to the Assistant Secretary any
information which this section requires the employer to make available.
Where there is a trade secret claim, such claim shall be made no later
than at the time the information is provided to the Assistant Secretary
so that suitable determinations of trade secret status can be made and
the necessary protections can be implemented.
(13) Nothing in this paragraph shall be construed as requiring the
disclosure under any circumstances of process or percentage of mixture
information which is trade secret.
(g) Employee information. (1) Upon an employee's first entering into
employment, and at least annually thereafter, each employer shall inform
current employees covered by this section of the following:
(i) The existence, location, and availability of any records covered
by this section;
(ii) The person responsible for maintaining and providing access to
records; and
(iii) Each employee's rights of access to these records.
(2) Each employer shall keep a copy of this section and its
appendices, and make copies readily available, upon request, to
employees. The employer shall also distribute to current employees any
informational materials concerning this section which are made available
to the employer by the Assistant Secretary of Labor for Occupational
Safety and Health.
(h) Transfer of records. (1) Whenever an employer is ceasing to do
business, the employer shall transfer all records subject to this
section to the successor employer. The successor employer shall receive
and maintain these records.
(2) Whenever an employer is ceasing to do business and there is no
successor employer to receive and maintain the records subject to this
standard, the employer shall notify affected current employees of their
rights of access to records at least three (3) months prior
[[Page 103]]
to the cessation of the employer's business.
(3) Whenever an employer either is ceasing to do business and there
is no successor employer to receive and maintain the records, or intends
to dispose of any records required to be preserved for at least thirty
(30) years, the employer shall:
(i) Transfer the records to the Director of the National Institute
for Occupational Safety and Health (NIOSH) if so required by a specific
occupational safety and health standard; or
(ii) Notify the Director of NIOSH in writing of the impending
disposal of records at least three (3) months prior to the disposal of
the records.
(4) Where an employer regularly disposes of records required to be
preserved for at least thirty (30) years, the employer may, with at
least (3) months notice, notify the Director of NIOSH on an annual basis
of the records intended to be disposed of in the coming year.
(i) Appendices. The information contained in appendices A and B to
this section is not intended, by itself, to create any additional
obligations not otherwise imposed by this section nor detract from any
existing obligation.
Appendix A to Sec. 1910.20--Sample Authorization Letter for the Release
of Employee Medical Record Information to a Designated Representative
(Non-Mandatory)
I, ---------- (full name of worker/patient), hereby authorize ------
------ (individual or organization holding the medical records) to
release to ------------ (individual or organization authorized to
receive the medical information), the following medical information from
my personal medical records:
_______________________________________________________________________
_______________________________________________________________________
(Describe generally the information desired to be released)
I give my permission for this medical information to be used for the
following purpose:
_______________________________________________________________________
_______________________________________________________________________
but I do not give permission for any other use or re-disclosure of this
information.
Note: Several extra lines are provided below so that you can place
additional restrictions on this authorization letter if you want to. You
may, however, leave these lines blank. On the other hand, you may want
to (1) specify a particular expiration date for this letter (if less
than one year); (2) describe medical information to be created in the
future that you intend to be covered by this authorization letter; or
(3) describe portions of the medical information in your records which
you do not intend to be released as a result of this letter.)
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
Full name of Employee or Legal Representative
_______________________________________________________________________
Signature of Employee or Legal Representative
_______________________________________________________________________
_______________________________________________________________________
Date of Signature
Appendix B to Sec. 1910.20--Availability of NIOSH Registry of Toxic
Effects of Chemical Substances (RTECS) (Non-Mandatory)
The final regulation, 29 CFR 1910.20, applies to all employee
exposure and medical records, and analyses thereof, of employees exposed
to toxic substances or harmful physical agents (paragraph (b)(2)). The
term toxic substance or harmful physical agent is defined by paragraph
(c)(13) to encompass chemical substances, biological agents, and
physical stresses for which there is evidence of harmful health effects.
The regulation uses the latest printed edition of the National Institute
for Occupational Safety and Health (NIOSH) Registry of Toxic Effects of
Chemical Substances (RTECS) as one of the chief sources of information
as to whether evidence of harmful health effects exists. If a substance
is listed in the latest printed RTECS, the regulation applies to
exposure and medical records (and analyses of these records) relevant to
employees exposed to the substance.
It is appropriate to note that the final regulation does not require
that employers purchase a copy of RTECS, and many employers need not
consult RTECS to ascertain whether their employee exposure or medical
records are subject to the rule. Employers who do not currently have the
latest printed edition of the NIOSH RTECS, however, may desire to obtain
a copy. The RTECS is issued in an annual printed edition as mandated by
section 20(a)(6) of the Occupational Safety and Health Act (29 U.S.C.
669(a)(6)).
The Introduction to the 1980 printed edition describes the RTECS as
follows:
``The 1980 edition of the Registry of Toxic Effects of Chemical
Substances, formerly known as the Toxic Substances list, is the ninth
revision prepared in compliance with the requirements of Section
20(a)(6) of the
[[Page 104]]
Occupational Safety and Health Act of 1970 (Public Law 91-596). The
original list was completed on June 28, 1971, and has been updated
annually in book format. Beginning in October 1977, quarterly revisions
have been provided in microfiche. This edition of the Registry contains
168,096 listings of chemical substances: 45,156 are names of different
chemicals with their associated toxicity data and 122,940 are synonyms.
This edition includes approximately 5,900 new chemical compounds that
did not appear in the 1979 Registry. (p. xi)
``The Registry's purposes are many, and it serves a variety of
users. It is a single source document for basic toxicity information and
for other data, such as chemical identifiers ad information necessary
for the preparation of safety directives and hazard evaluations for
chemical substances. The various types of toxic effects linked to
literature citations provide researchers and occupational health
scientists with an introduction to the toxicological literature, making
their own review of the toxic hazards of a given substance easier. By
presenting data on the lowest reported doses that produce effects by
several routes of entry in various species, the Registry furnishes
valuable information to those responsible for preparing safety data
sheets for chemical substances in the workplace. Chemical and production
engineers can use the Registry to identify the hazards which may be
associated with chemical intermediates in the development of final
products, and thus can more readily select substitutes or alternative
processes which may be less hazardous. Some organizations, including
health agencies and chemical companies, have included the NIOSH Registry
accession numbers with the listing of chemicals in their files to
reference toxicity information associated with those chemicals. By
including foreign language chemical names, a start has been made toward
providing rapid identification of substances produced in other
countries. (p. xi)
``In this edition of the Registry, the editors intend to identify
``all known toxic substances'' which may exist in the environment and to
provide pertinent data on the toxic effects from known doses entering an
organism by any route described. (p xi)
``It must be reemphasized that the entry of a substance in the
Registry does not automatically mean that it must be avoided. A listing
does mean, however, that the substance has the documented potential of
being harmful if misused, and care must be exercised to prevent tragic
consequences. Thus, the Registry lists many substances that are common
in everyday life and are in nearly every household in the United States.
One can name a variety of such dangerous substances: prescription and
non-prescription drugs; food additives; pesticide concentrates, sprays,
and dusts; fungicides; herbicides; paints; glazes, dyes; bleaches and
other household cleaning agents; alkalies; and various solvents and
diluents. The list is extensive because chemicals have become an
integral part of our existence.''
The RTECS printed edition may be purchased from the Superintendent
of Documents, U.S. Government Printing Office (GPO), Washington, DC
20402 (202-783-3238).
Some employers may desire to subscribe to the quarterly update to
the RTECS which is published in a microfiche edition. An annual
subscription to the quarterly microfiche may be purchased from the GPO
(Order the ``Microfiche Edition, Registry of Toxic Effects of Chemical
Substances''). Both the printed edition and the microfiche edition of
RTECS are available for review at many university and public libraries
throughout the country. The latest RTECS editions may also be examined
at the OSHA Technical Data Center, Room N2439--Rear, United States
Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210
(202-523-9700), or at any OSHA Regional or Area Office (See, major city
telephone directories under United States Government-Labor Department).
[53 FR 38163, Sept. 29, 1988; 53 FR 49981, Dec. 13, 1988, as amended at
54 FR 24333, June 7, 1989; 55 FR 26431, June 28, 1990; 61 FR 9235, Mar.
7, 1996. Redesignated at 61 FR 31430, June 20, 1996]
Sec. 1910.1025 Lead.
(a) Scope and application. (1) This section applies to all
occupational exposure to lead, except as provided in paragraph (a)(2).
(2) This section does not apply to the construction industry or to
agricultural operations covered by 29 CFR Part 1928.
(b) Definitions. Action level means employee exposure, without
regard to the use of respirators, to an airborne concentration of lead
of 30 micrograms per cubic meter of air (30 g/m3)
averaged over an 8-hour period.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Director means the Director, National Institute for Occupational
Safety and Health (NIOSH), U.S. Department of Health, Education, and
Welfare, or designee.
Lead means metallic lead, all inorganic lead compounds, and organic
lead soaps. Excluded from this definition are all other organic lead
compounds.
[[Page 105]]
(c) Permissible exposure limit (PEL). (1) The employer shall assure
that no employee is exposed to lead at concentrations greater than fifty
micrograms per cubic meter of air (50 g/m3) averaged
over an 8-hour period.
(2) If an employee is exposed to lead for more than 8 hours in any
work day, the permissible exposure limit, as a time weighted average
(TWA) for that day, shall be reduced according to the following formula:
Maximum permissible limit (in g/m3)=400hours
worked in the day.
(3) When respirators are used to supplement engineering and work
practice controls to comply with the PEL and all the requirements of
paragraph (f) have been met, employee exposure, for the purpose of
determining whether the employer has complied with the PEL, may be
considered to be at the level provided by the protection factor of the
respirator for those periods the respirator is worn. Those periods may
be averaged with exposure levels during periods when respirators are not
worn to determine the employee's daily TWA exposure.
(d) Exposure monitoring--(1) General. (i) For the purposes of
paragraph (d), employee exposure is that exposure which would occur if
the employee were not using a respirator.
(ii) With the exception of monitoring under paragraph (d)(3), the
employer shall collect full shift (for at least 7 continuous hours)
personal samples including at least one sample for each shift for each
job classification in each work area.
(iii) Full shift personal samples shall be representative of the
monitored employee's regular, daily exposure to lead.
(2) Initial determination. Each employer who has a workplace or work
operation covered by this standard shall determine if any exployee may
be exposed to lead at or above the action level.
(3) Basis of initial determination. (i) The employer shall monitor
employee exposures and shall base initial determinations on the employee
exposure monitoring results and any of the following, relevant
considerations:
(A) Any information, observations, or calculations which would
indicate employee exposure to lead;
(B) Any previous measurements of airborne lead; and
(C) Any employee complaints of symptoms which may be attributable to
exposure to lead.
(ii) Monitoring for the initial determination may be limited to a
representative sample of the exposed employees who the employer
reasonably believes are exposed to the greatest airborne concentrations
of lead in the workplace.
(iii) Measurements of airborne lead made in the preceding 12 months
may be used to satisfy the requirement to monitor under paragraph
(d)(3)(i) if the sampling and analytical methods used meet the accuracy
and confidence levels of paragraph (d)(9) of this section.
(4) Positive initial determination and initial monitoring. (i) Where
a determination conducted under paragraphs (d) (2) and (3) of this
section shows the possibility of any employee exposure at or above the
action level, the employer shall conduct monitoring which is
representative of the exposure for each employee in the workplace who is
exposed to lead.
(ii) Measurements of airborne lead made in the preceding 12 months
may be used to satisfy this requirement if the sampling and analytical
methods used meet the accuracy and confidence levels of paragraph (d)(9)
of this section.
(5) Negative initial determination. Where a determination, conducted
under paragraphs (d) (2) and (3) of this section is made that no
employee is exposed to airborne concentrations of lead at or above the
action level, the employer shall make a written record of such
determination. The record shall include at least the information
specified in paragraph (d)(3) of this section and shall also include the
date of determination, location within the worksite, and the name and
social security number of each employee monitored.
(6) Frequency. (i) If the initial monitoring reveals employee
exposure to be below the action level the measurements need not be
repeated except as otherwise provided in paragraph (d)(7) of this
section.
[[Page 106]]
(ii) If the initial determination or subsequent monitoring reveals
employee exposure to be at or above the action level but below the
permissible exposure limit the employer shall repeat monitoring in
accordance with this paragraph at least every 6 months. The employer
shall continue monitoring at the required frequency until at least two
consecutive measurements, taken at least 7 days apart, are below the
action level at which time the employer may discontinue monitoring for
that employee except as otherwise provided in paragraph (d)(7) of this
section.
(iii) If the initial monitoring reveals that employee exposure is
above the permissible exposure limit the employer shall repeat
monitoring quarterly. The employer shall continue monitoring at the
required frequency until at least two consecutive measurements, taken at
least 7 days apart, are below the PEL but at or above the action level
at which time the employer shall repeat monitoring for that employee at
the frequency specified in paragraph (d)(6)(ii), except as otherwise
provided in paragraph (d)(7) of this section.
(7) Additional monitoring. Whenever there has been a production,
process, control or personnel change which may result in new or
additional exposure to lead, or whenever the employer has any other
reason to suspect a change which may result in new or additional
exposures to lead, additional monitoring in accordance with this
paragraph shall be conducted.
(8) Employee notification. (i) Within 5 working days after the
receipt of monitoring results, the employer shall notify each employee
in writing of the results which represent that employee's exposure.
(ii) Whenever the results indicate that the representative employee
exposure, without regard to respirators, exceeds the permissible
exposure limit, the employer shall incude in the written notice a
statement that the permissible exposure limit was exceeded and a
description of the corrective action taken or to be taken to reduce
exposure to or below the permissible exposure limit.
(9) Accuracy of measurement. The employer shall use a method of
monitoring and analysis which has an accuracy (to a confidence level of
95%) of not less than plus or minus 20 percent for airborne
concentrations of lead equal to or greater than 30 g/
m3.
(e) Methods of compliance--(1) Engineering and work practice
controls. (i) Where any employee is exposed to lead above the
permissible exposure limit for more than 30 days per year, the employer
shall implement engineering and work practice controls (including
administrative controls) to reduce and maintain employee exposure to
lead in accordance with the implementation schedule in Table I below,
except to the extent that the employer can demonstrate that such
controls are not feasible. Wherever the engineering and work practice
controls which can be instituted are not sufficient to reduce employee
exposure to or below the permissible exposure limit, the employer shall
nonetheless use them to reduce exposures to the lowest feasible level
and shall supplement them by the use of respiratory protection which
complies with the requirements of paragraph (f) of this section.
(ii) Where any employee is exposed to lead above the permissible
exposure limit, but for 30 days or less per year, the employer shall
implement engineering controls to reduce exposures to 200 g/
m3, but thereafter may implement any combination of
engineering, work practice (including administrative controls), and
respiratory controls to reduce and maintain employee exposure to lead to
or below 50 g/m3.
Table I
------------------------------------------------------------------------
Compliance dates: 1 (50
Industry g/m\3\)
------------------------------------------------------------------------
Lead chemicals, secondary copper smelting July 19, 1996.
Nonferrous foundries..................... July 19, 1996. \2\
Brass and bronze ingot manufacture....... 6 years.\3\
------------------------------------------------------------------------
\1\ Calculated by counting from the date the stay on implementation of
paragraph (e)(1) was lifted by the U.S. Court of Appeals for the
District of Columbia, the number of years specified in the 1978 lead
standard and subsequent amendments for compliance with the PEL of 50
g/m\3\ for exposure to airborne concentrations of lead
levels for the particular industry.
\2\ Large nonferrous foundries (20 or more employees) are required to
achieve the PEL of 50 g/m\3\ by means of engineering and
work practice controls. Small nonferrous foundries (fewer than 20
employees) are required to achieve an 8-hour TWA of 75 g/
m\3\ by such controls.
[[Page 107]]
\3\ Expressed as the number of years from the date on which the Court
lifts the stay on the implementation of paragraph (e)(1) for this
industry for employers to achieve a lead in air concentration of 75
g/m\3\. Compliance with paragraph (e) in this industry is
determined by a compliance directive that incorporates elements from
the settlement agreement between OSHA and representatives of the
industry.
(2) Respiratory protection. Where engineering and work practice
controls do not reduce employee exposure to or below the 50 g/
m3permissible exposure limit, the employer shall supplement
these controls with respirators in accordance with paragraph (f).
(3) Compliance program. (i) Each employer shall establish and
implement a written compliance program to reduce exposures to or below
the permissible exposure limit, and interim levels if applicable, solely
by means of engineering and work practice controls in accordance with
the implementation schedule in paragraph (e)(1).
(ii) Written plans for these compliance programs shall include at
least the following:
(A) A description of each operation in which lead is emitted; e.g.
machinery used, material processed, controls in place, crew size,
employee job responsibilities, operating procedures and maintenance
practices;
(B) A description of the specific means that will be employed to
achieve compliance, including engineering plans and studies used to
determine methods selected for controlling exposure to lead;
(C) A report of the technology considered in meeting the permissible
exposure limit;
(D) Air monitoring data which documents the source of lead
emissions;
(E) A detailed schedule for implementation of the program, including
documentation such as copies of purchase orders for equipment,
construction contracts, etc.;
(F) A work practice program which includes items required under
paragraphs (g), (h) and (i) of this regulation;
(G) An administrative control schedule required by paragraph (e)(6),
if applicable;
(H) Other relevant information.
(iii) Written programs shall be submitted upon request to the
Assistant Secretary and the Director, and shall be available at the
worksite for examination and copying by the Assistant Secretary,
Director, any affected employee or authorized employee representatives.
(iv) Written programs shall be revised and updated at least every 6
months to reflect the current status of the program.
(4) Mechanical ventilation. (i) When ventilation is used to control
exposure, measurements which demonstrate the effectiveness of the system
in controlling exposure, such as capture velocity, duct velocity, or
static pressure shall be made at least every 3 months. Measurements of
the system's effectiveness in controlling exposure shall be made within
5 days of any change in production, process, or control which might
result in a change in employee exposure to lead.
(ii) Recirculation of air. If air from exhaust ventilation is
recirculated into the workplace, the employer shall assure that (A) the
system has a high efficiency filter with reliable back-up filter; and
(B) controls to monitor the concentration of lead in the return air and
to bypass the recirculation system automatically if it fails are
installed, operating, and maintained.
(5) Administrative controls. If administrative controls are used as
a means of reducing employees TWA exposure to lead, the employer shall
establish and implement a job rotation schedule which includes:
(i) Name or identification number of each affected employee;
(ii) Duration and exposure levels at each job or work station where
each affected employee is located; and
(iii) Any other information which may be useful in assessing the
reliability of administrative controls to reduce exposure to lead.
(f) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide
respirators that comply with the requirements of this paragraph.
Respirators must be used during:
(i) Periods necessary to install or implement engineering or work-
practice controls.
(ii) Work operations for which engineering and work-practice
controls are
[[Page 108]]
not sufficient to reduce employee exposures to or below the permissible
exposure limit.
(iii) Periods when an employee requests a respirator.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance with 29 CFR 1910.134 (b)
through (d) (except (d)(1)(iii)), and (f) through (m).
(ii) If an employee has breathing difficulty during fit testing or
respirator use, the employer must provide the employee with a medical
examination in accordance with paragraph (j)(3)(i)(C) of this section to
determine whether or not the employee can use a respirator while
performing the required duty.
Table II--Respiratory Protection for Lead Aerosols
------------------------------------------------------------------------
Airborne concentration of
lead or condition of use Required respirator
------------------------------------------------------------------------
Not in excess of 0.5 mg/m\3\ Half-mask, air-purifying respirator
(10X PEL). equipped with high efficiency
filters.\2\ \3\
Not in excess of 2.5 mg/m\3\ Full facepiece, air-purifying respirator
(50X PEL). with high efficiency filters.\3\
Not in excess of 50 mg/m\3\ (1) Any powered, air-purifying respirator
(1000X PEL). with high efficiency filters\3\; or (2)
Half-mask supplied-air respirator
operated in positive-pressure mode.\2\
Not in excess of 100 mg/m\3\ Supplied-air respirators with full
(2000XPEL). facepiece, hood, helmet, or suit,
operated in positive pressure mode.
Greater than 100 mg/m\3\, Full facepiece, self-contained breathing
unknown concentration or apparatus operated in positive-pressure
fire fighting. mode.
------------------------------------------------------------------------
\1\ Respirators specified for high concentrations can be used at lower
concentrations of lead.
\2\ Full facepiece is required if the lead aerosols cause eye or skin
irritation at the use concentrations.
\3\ A high efficiency particulate filter means 99.97 percent efficient
against 0.3 micron size particles.
(3) Respirator selection. (i) The employer must select the
appropriate respirator or combination of respirators from Table II of
this section.
(ii) The employer must provide a powered air-purifying respirator
instead of the respirator specified in Table II of this section when an
employee chooses to use this type of respirator and such a respirator
provides adequate protection to the employee.
(g) Protective work clothing and equipment--(1) Provision and use.
If an employee is exposed to lead above the PEL, without regard to the
use of respirators or where the possibility of skin or eye irritation
exists, the employer shall provide at no cost to the employee and assure
that the employee uses appropriate protective work clothing and
equipment such as, but not limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, hats, and shoes or disposable shoe coverlets; and
(iii) Face shields, vented goggles, or other appropriate protective
equipment which complies with Sec. 1910.133 of this Part.
(2) Cleaning and replacement. (i) The employer shall provide the
protective clothing required in paragraph (g)(1) of this section in a
clean and dry condition at least weekly, and daily to employees whose
exposure levels without regard to a respirator are over 200 g/
m3of lead as an 8-hour TWA.
(ii) The employer shall provide for the cleaning, laundering, or
disposal of protective clothing and equipment required by paragraph
(g)(1) of this section.
(iii) The employer shall repair or replace required protective
clothing and equipment as needed to maintain their effectiveness.
(iv) The employer shall assure that all protective clothing is
removed at the completion of a work shift only in change rooms provided
for that purpose as prescribed in paragraph (i)(2) of this section.
(v) The employer shall assure that contaminated protective clothing
which is to be cleaned, laundered, or disposed of, is placed in a closed
container in the change-room which prevents dispersion of lead outside
the container.
(vi) The employer shall inform in writing any person who cleans or
launders protective clothing or equipment of the potentially harmful
effects of exposure to lead.
(vii) The employer shall assure that the containers of contaminated
protective clothing and equipment required
[[Page 109]]
by paragraph (g)(2)(v) are labelled as follows:
CAUTION: CLOTHING CONTAMINATED WITH LEAD. DO NOT REMOVE DUST BY BLOWING
OR SHAKING. DISPOSE OF LEAD CONTAMINATED WASH WATER IN ACCORDANCE WITH
APPLICABLE LOCAL, STATE, OR FEDERAL REGULATIONS.
(viii) The employer shall prohibit the removal of lead from
protective clothing or equipment by blowing, shaking, or any other means
which disperses lead into the air.
(h) Housekeeping--(1) Surfaces. All surfaces shall be maintained as
free as practicable of accumulations of lead.
(2) Cleaning floors. (i) Floors and other surfaces where lead
accumulates may not be cleaned by the use of compressed air.
(ii) Shoveling, dry or wet sweeping, and brushing may be used only
where vacuuming or other equally effective methods have been tried and
found not to be effective.
(3) Vacuuming. Where vacuuming methods are selected, the vacuums
shall be used and emptied in a manner which minimizes the reentry of
lead into the workplace.
(i) Hygiene facilities and practices. (1) The employer shall assure
that in areas where employees are exposed to lead above the PEL, without
regard to the use of respirators, food or beverage is not present or
consumed, tobacco products are not present or used, and cosmetics are
not applied, except in change rooms, lunchrooms, and showers required
under paragraphs (i)(2) through (i)(4) of this section.
(2) Change rooms. (i) The employer shall provide clean change rooms
for employees who work in areas where their airborne exposure to lead is
above the PEL, without regard to the use of respirators.
(ii) The employer shall assure that change rooms are equipped with
separate storage facilities for protective work clothing and equipment
and for street clothes which prevent cross-contamination.
(3) Showers. (i) The employer shall assure that employees who work
in areas where their airborne exposure to lead is above the PEL, without
regard to the use of respirators, shower at the end of the work shift.
(ii) The employer shall provide shower facilities in accordance with
Sec. 1910.141 (d)(3) of this part.
(iii) The employer shall assure that employees who are required to
shower pursuant to paragraph (i)(3)(i) do not leave the workplace
wearing any clothing or equipment worn during the work shift.
(4) Lunchrooms. (i) The employer shall provide lunchroom facilities
for employees who work in areas where their airborne exposure to lead is
above the PEL, without regard to the use of respirators.
(ii) The employer shall assure that lunchroom facilities have a
temperature controlled, positive pressure, filtered air supply, and are
readily accessible to employees.
(iii) The employer shall assure that employees who work in areas
where their airborne exposure to lead is above the PEL without regard to
the use of a respirator wash their hands and face prior to eating,
drinking, smoking or applying cosmetics.
(iv) The employer shall assure that employees do not enter lunchroom
facilities with protective work clothing or equipment unless surface
lead dust has been removed by vacuuming, downdraft booth, or other
cleaning method.
(5) Lavatories. The employer shall provide an adequate number of
lavatory facilities which comply with Sec. 1910.141(d) (1) and (2) of
this part.
(j) Medical surveillance--(1) General. (i) The employer shall
institute a medical surveillance program for all employees who are or
may be exposed above the action level for more than 30 days per year.
(ii) The employer shall assure that all medical examinations and
procedures are performed by or under the supervision of a licensed
physician.
(iii) The employer shall provide the required medical surveillance
including multiple physician review under paragraph (j)(3)(iii) without
cost to employees and at a reasonable time and place.
(2) Biological monitoring--(i) Blood lead and ZPP level sampling and
analysis. The employer shall make available biological monitoring in the
form of blood sampling and analysis for lead and zinc protoporphyrin
levels to each employee
[[Page 110]]
covered under paragraph (j)(1)(i) of this section on the following
schedule:
(A) At least every 6 months to each employee covered under paragraph
(j)(1)(i) of this section;
(B) At least every two months for each employee whose last blood
sampling and analysis indicated a blood lead level at or above 40
g/100 g of whole blood. This frequency shall continue until
two consecutive blood samples and analyses indicate a blood lead level
below 40 g/100 g of whole blood; and
(C) At least monthly during the removal period of each employee
removed from exposure to lead due to an elevated blood lead level.
(ii) Follow-up blood sampling tests. Whenever the results of a blood
lead level test indicate that an employee's blood lead level exceeds the
numerical criterion for medical removal under paragraph (k)(1)(i)(A) of
this section, the employer shall provide a second (follow-up) blood
sampling test within two weeks after the employer receives the results
of the first blood sampling test.
(iii) Accuracy of blood lead level sampling and analysis. Blood lead
level sampling and analysis provided pursuant to this section shall have
an accuracy (to a confidence level of 95 percent) within plus or minus
15 percent or 6 g/100ml, whichever is greater, and shall be
conducted by a laboratory licensed by the Center for Disease Control,
United States Department of Health, Education and Welfare (CDC) or which
has received a satisfactory grade in blood lead proficiency testing from
CDC in the prior twelve months.
(iv) Employee notification. Within five working days after the
receipt of biological monitoring results, the employer shall notify in
writing each employee whose blood lead level exceeds 40 g/100
g: (A) of that employee's blood lead level and (B) that the standard
requires temporary medical removal with Medical Removal Protection
benefits when an employee's blood lead level exceeds the numerical
criterion for medical removal under paragraph (k)(1)(i) of this section.
(3) Medical examinations and consultations--(i) Frequency. The
employer shall make available medical examinations and consultations to
each employee covered under paragraph (j)(1)(i) of this section on the
following schedule:
(A) At least annually for each employee for whom a blood sampling
test conducted at any time during the preceding 12 months indicated a
blood lead level at or above 40 g/100 g;
(B) Prior to assignment for each employee being assigned for the
first time to an area in which airborne concentrations of lead are at or
above the action level;
(C) As soon as possible, upon notification by an employee either
that the employee has developed signs or symptoms commonly associated
with lead intoxication, that the employee desires medical advice
concerning the effects of current or past exposure to lead on the
employee's ability to procreate a healthy child, or that the employee
has demonstrated difficulty in breathing during a respirator fitting
test or during use; and
(D) As medically appropriate for each employee either removed from
exposure to lead due to a risk of sustaining material impairment to
health, or otherwise limited pursuant to a final medical determination.
(ii) Content. Medical examinations made available pursuant to
paragraph (j)(3)(i) (A) through (B) of this section shall include the
following elements:
(A) A detailed work history and a medical history, with particular
attention to past lead exposure (occupational and non-occupational),
personal habits (smoking, hygiene), and past gastrointestinal,
hematologic, renal, cardiovascular, reproductive and neurological
problems;
(B) A thorough physical examination, with particular attention to
teeth, gums, hematologic, gastrointestinal, renal, cardiovascular, and
neurological systems. Pulmonary status should be evaluated if
respiratory protection will be used;
(C) A blood pressure measurement;
(D) A blood sample and analysis which determines:
(1) Blood lead level;
(2) Hemoglobin and hematocrit determinations, red cell indices, and
examination of peripheral smear morphology;
(3) Zinc protoporphyrin;
[[Page 111]]
(4) Blood urea nitrogen; and,
(5) Serum creatinine;
(E) A routine urinalysis with microscopic examination; and
(F) Any laboratory or other test which the examining physician deems
necessary by sound medical practice.
The content of medical examinations made available pursuant to paragraph
(j)(3)(i) (C) through (D) of this section shall be determined by an
examining physician and, if requested by an employee, shall include
pregnancy testing or laboratory evaluation of male fertility.
(iii) Multiple physician review mechanism. (A) If the employer
selects the initial physician who conducts any medical examination or
consultation provided to an employee under this section, the employee
may designate a second physician:
(1) To review any findings, determinations or recommendations of the
initial physician; and
(2) To conduct such examinations, consultations, and laboratory
tests as the second physician deems necessary to facilitate this review.
(B) The employer shall promptly notify an employee of the right to
seek a second medical opinion after each occasion that an initial
physician conducts a medical examination or consultation pursuant to
this section. The employer may condition its participation in, and
payment for, the multiple physician review mechanism upon the employee
doing the following within fifteen (15) days after receipt of the
foregoing notification, or receipt of the initial physician's written
opinion, whichever is later:
(1) The employee informing the employer that he or she intends to
seek a second medical opinion, and
(2) The employee initiating steps to make an appointment with a
second physician.
(C) If the findings, determinations or recommendations of the second
physician differ from those of the initial physician, then the employer
and the employee shall assure that efforts are made for the two
physicians to resolve any disagreement.
(D) If the two physicians have been unable to quickly resolve their
disagreement, then the employer and the employee through their
respective physicians shall designate a third physician:
(1) To review any findings, determinations or recommendations of the
prior physicians; and
(2) To conduct such examinations, consultations, laboratory tests
and discussions with the prior physicians as the third physician deems
necessary to resolve the disagreement of the prior physicians.
(E) The employer shall act consistent with the findings,
determinations and recommendations of the third physician, unless the
employer and the employee reach an agreement which is otherwise
consistent with the recommendations of at least one of the three
physicians.
(iv) Information provided to examining and consulting physicians.
(A) The employer shall provide an initial physician conducting a medical
examination or consultation under this section with the following
information:
(1) A copy of this regulation for lead including all Appendices;
(2) A description of the affected employee's duties as they relate
to the employee's exposure;
(3) The employee's exposure level or anticipated exposure level to
lead and to any other toxic substance (if applicable);
(4) A description of any personal protective equipment used or to be
used;
(5) Prior blood lead determinations; and
(6) All prior written medical opinions concerning the employee in
the employer's possession or control.
(B) The employer shall provide the foregoing information to a second
or third physician conducting a medical examination or consultation
under this section upon request either by the second or third physician,
or by the employee.
(v) Written medical opinions. (A) The employer shall obtain and
furnish the employee with a copy of a written medical opinion from each
examining or consulting physician which contains the following
information:
(1) The physician's opinion as to whether the employee has any
detected medical condition which would place
[[Page 112]]
the employee at increased risk of material impairment of the employee's
health from exposure to lead;
(2) Any recommended special protective measures to be provided to
the employee, or limitations to be placed upon the employee's exposure
to lead;
(3) Any recommended limitation upon the employee's use of
respirators, including a determination of whether the employee can wear
a powered air purifying respirator if a physician determines that the
employee cannot wear a negative pressure respirator; and
(4) The results of the blood lead determinations.
(B) The employer shall instruct each examining and consulting
physician to:
(1) Not reveal either in the written opinion, or in any other means
of communication with the employer, findings, including laboratory
results, or diagnoses unrelated to an employee's occupational exposure
to lead; and
(2) Advise the employee of any medical condition, occupational or
nonoccupational, which dictates further medical examination or
treatment.
(vi) Alternate Physician Determination Mechanisms. The employer and
an employee or authorized employee representative may agree upon the use
of any expeditious alternate physician determination mechanism in lieu
of the multiple physician review mechanism provided by this paragraph so
long as the alternate mechanism otherwise satisfies the requirements
contained in this paragraph.
(4) Chelation. (i) The employer shall assure that any person whom he
retains, employs, supervises or controls does not engage in prophylactic
chelation of any employee at any time.
(ii) If therapeutic or diagnostic chelation is to be performed by
any person in paragraph (j)(4)(i), the employer shall assure that it be
done under the supervision of a licensed physician in a clinical setting
with thorough and appropriate medical monitoring and that the employee
is notified in writing prior to its occurrence.
(k) Medical Removal Protection--(1) Temporary medical removal and
return of an employee--(i) Temporary removal due to elevated blood lead
levels. (A) The employer shall remove an employee from work having an
exposure to lead at or above the action level on each occasion that a
periodic and a follow-up blood sampling test conducted pursuant to this
section indicate that the employee's blood lead level is at or above 60
g/100 g of whole blood; and
(B) The employer shall remove an employee from work having an
exposure to lead at or above the action level on each occasion that the
average of the last three blood sampling tests conducted pursuant to
this section (or the average of all blood sampling tests conducted over
the previous six (6) months, whichever is longer) indicates that the
employee's blood lead level is at or above 50 g/100 g of whole
blood; provided, however, that an employee need not be removed if the
last blood sampling test indicates a blood lead level at or below 40
g/100 g of whole blood.
(ii) Temporary removal due to a final medical determination. (A) The
employer shall remove an employee from work having an exposure to lead
at or above the action level on each occasion that a final medical
determination results in a medical finding, determination, or opinion
that the employee has a detected medical condition which places the
employee at increased risk of material impairment to health from
exposure to lead.
(B) For the purposes of this section, the phrase ``final medical
determination'' shall mean the outcome of the multiple physician review
mechanism or alternate medical determination mechanism used pursuant to
the medical surveillance provisions of this section.
(C) Where a final medical determination results in any recommended
special protective measures for an employee, or limitations on an
employee's exposure to lead, the employer shall implement and act
consistent with the recommendation.
(iii) Return of the employee to former job status. (A) The employer
shall return an employee to his or her former job status:
(1) For an employee removed due to a blood lead level at or above 60
g/100 g, or due to an average blood lead level at or above 50
g/100 g, when two consecutive blood sampling tests indicate
that
[[Page 113]]
the employee's blood lead level is at or below 40 g/100 g of
whole blood;
(2) For an employee removed due to a final medical determination,
when a subsequent final medical determination results in a medical
finding, determination, or opinion that the employee no longer has a
detected medical condition which places the employee at increased risk
of material impairment to health from exposure to lead.
(B) For the purposes of this section, the requirement that an
employer return an employee to his or her former job status is not
intended to expand upon or restrict any rights an employee has or would
have had, absent temporary medical removal, to a specific job
classification or position under the terms of a collective bargaining
agreement.
(iv) Removal of other employee special protective measure or
limitations. The employer shall remove any limitations placed on an
employee or end any special protective measures provided to an employee
pursuant to a final medical determination when a subsequent final
medical determination indicates that the limitations or special
protective measures are no longer necessary.
(v) Employer options pending a final medical determination. Where
the multiple physician review mechanism, or alternate medical
determination mechanism used pursuant to the medical surveillance
provisions of this section, has not yet resulted in a final medical
determination with respect to an employee, the employer shall act as
follows:
(A) Removal. The employer may remove the employee from exposure to
lead, provide special protective measures to the employee, or place
limitations upon the employee, consistent with the medical findings,
determinations, or recommendations of any of the physicians who have
reviewed the employee's health status.
(B) Return. The employer may return the employee to his or her
former job status, end any special protective measures provided to the
employee, and remove any limitations placed upon the employee,
consistent with the medical findings, determinations, or recommendations
of any of the physicians who have reviewed the employee's health status,
with two exceptions. If
(1) the initial removal, special protection, or limitation of the
employee resulted from a final medical determination which differed from
the findings, determinations, or recommendations of the initial
physician or
(2) The employee has been on removal status for the preceding
eighteen months due to an elevated blood lead level, then the employer
shall await a final medical determination.
(2) Medical removal protection benefits--(i) Provision of medical
removal protection benefits. The employer shall provide to an employee
up to eighteen (18) months of medical removal protection benefits on
each occasion that an employee is removed from exposure to lead or
otherwise limited pursuant to this section.
(ii) Definition of medical removal protection benefits. For the
purposes of this section, the requirement that an employer provide
medical removal protection benefits means that the employer shall
maintain the earnings, seniority and other employment rights and
benefits of an employee as though the employee had not been removed from
normal exposure to lead or otherwise limited.
(iii) Follow-up medical surveillance during the period of employee
removal or limitation. During the period of time that an employee is
removed from normal exposure to lead or otherwise limited, the employer
may condition the provision of medical removal protection benefits upon
the employee's participation in follow-up medical surveillance made
available pursuant to this section.
(iv) Workers' compensation claims. If a removed employee files a
claim for workers' compensation payments for a lead-related disability,
then the employer shall continue to provide medical removal protection
benefits pending disposition of the claim. To the extent that an award
is made to the employee for earnings lost during the period of removal,
the employer's medical removal protection obligation shall be reduced by
such amount. The employer shall receive no credit for
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workers' compensation payments received by the employee for treatment
related expenses.
(v) Other credits. The employer's obligation to provide medical
removal protection benefits to a removed employee shall be reduced to
the extent that the employee receives compensation for earnings lost
during the period of removal either from a publicly or employer-funded
compensation program, or receives income from employment with another
employer made possible by virtue of the employee's removal.
(vi) Employees whose blood lead levels do not adequately decline
within 18 months of removal. The employer shall take the following
measures with respect to any employee removed from exposure to lead due
to an elevated blood lead level whose blood lead level has not declined
within the past eighteen (18) months of removal so that the employee has
been returned to his or her former job status:
(A) The employer shall make available to the employee a medical
examination pursuant to this section to obtain a final medical
determination with respect to the employee;
(B) The employer shall assure that the final medical determination
obtained indicates whether or not the employee may be returned to his or
her former job status, and if not, what steps should be taken to protect
the employee's health;
(C) Where the final medical determination has not yet been obtained,
or once obtained indicates that the employee may not yet be returned to
his or her former job status, the employer shall continue to provide
medical removal protection benefits to the employee until either the
employee is returned to former job status, or a final medical
determination is made that the employee is incapable of ever safely
returning to his or her former job status.
(D) Where the employer acts pursuant to a final medical
determination which permits the return of the employee to his or her
former job status despite what would otherwise be an unacceptable blood
lead level, later questions concerning removing the employee again shall
be decided by a final medical determination. The employer need not
automatically remove such an employee pursuant to the blood lead level
removal criteria provided by this section.
(vii) Voluntary Removal or Restriction of An Employee. Where an
employer, although not required by this section to do so, removes an
employee from exposure to lead or otherwise places limitations on an
employee due to the effects of lead exposure on the employee's medical
condition, the employer shall provide medical removal protection
benefits to the employee equal to that required by paragraph (k)(2)(i)
of this section.
(l) Employee information and training--(1) Training program. (i)
Each employer who has a workplace in which there is a potential exposure
to airborne lead at any level shall inform employees of the content of
Appendices A and B of this regulation.
(ii) The employer shall institute a training program for and assure
the participation of all employees who are subject to exposure to lead
at or above the action level or for whom the possibility of skin or eye
irritation exists.
(iii) The employer shall provide initial training by 180 days from
the effective date for those employees covered by paragraph (l)(1) (ii)
on the standard's effective date and prior to the time of initial job
assignment for those employees subsequently covered by this paragraph.
(iv) The training program shall be repeated at least annually for
each employee.
(v) The employer shall assure that each employee is informed of the
following:
(A) The content of this standard and its appendices;
(B) The specific nature of the operations which could result in
exposure to lead above the action level;
(C) The purpose, proper selection, fitting, use, and limitations of
respirators;
(D) The purpose and a description of the medical surveillance
program, and the medical removal protection program including
information concerning the adverse health effects associated with
excessive exposure to lead (with
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particular attention to the adverse reproductive effects on both males
and females);
(E) The engineering controls and work practices associated with the
employee's job assignment;
(F) The contents of any compliance plan in effect; and
(G) Instructions to employees that chelating agents should not
routinely be used to remove lead from their bodies and should not be
used at all except under the direction of a licensed physician;
(2) Access to information and training materials. (i) The employer
shall make readily available to all affected employees a copy of this
standard and its appendices.
(ii) The employer shall provide, upon request, all materials
relating to the employee information and training program to the
Assistant Secretary and the Director.
(iii) In addition to the information required by paragraph
(l)(1)(v), the employer shall include as part of the training program,
and shall distribute to employees, any materials pertaining to the
Occupational Safety and Health Act, the regulations issued pursuant to
that Act, and this lead standard, which are made available to the
employer by the Assistant Secretary.
(m) Signs--(1) General. (i) The employer may use signs required by
other statutes, regulations or ordinances in addition to, or in
combination with, signs required by this paragraph.
(ii) The employer shall assure that no statement appears on or near
any sign required by this paragraph which contradicts or detracts from
the meaning of the required sign.
(2) Signs. (i) The employer shall post the following warning signs
in each work area where the PEL is exceeded:
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
(ii) The employer shall assure that signs required by this paragraph
are illuminated and cleaned as necessary so that the legend is readily
visible.
(n) Recordkeeping--(1) Exposure monitoring. (i) The employer shall
establish and maintain an accurate record of all monitoring required in
paragraph (d) of this section.
(ii) This record shall include:
(A) The date(s), number, duration, location and results of each of
the samples taken, including a description of the sampling procedure
used to determine representative employee exposure where applicable;
(B) A description of the sampling and analytical methods used and
evidence of their accuracy;
(C) The type of respiratory protective devices worn, if any;
(D) Name, social security number, and job classification of the
employee monitored and of all other employees whose exposure the
measurement is intended to represent; and
(E) The environmental variables that could affect the measurement of
employee exposure.
(iii) The employer shall maintain these monitoring records for at
least 40 years or for the duration of employment plus 20 years,
whichever is longer.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance as required by paragraph (j) of this section.
(ii) This record shall include:
(A) The name, social security number, and description of the duties
of the employee;
(B) A copy of the physician's written opinions;
(C) Results of any airborne exposure monitoring done for that
employee and the representative exposure levels supplied to the
physician; and
(D) Any employee medical complaints related to exposure to lead.
(iii) The employer shall keep, or assure that the examining
physician keeps, the following medical records:
(A) A copy of the medical examination results including medical and
work history required under paragraph (j) of this section;
(B) A description of the laboratory procedures and a copy of any
standards or guidelines used to interpret the test results or references
to that information;
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(C) A copy of the results of biological monitoring.
(iv) The employer shall maintain or assure that the physician
maintains those medical records for at least 40 years, or for the
duration of employment plus 20 years, whichever is longer.
(3) Medical removals. (i) The employer shall establish and maintain
an accurate record for each employee removed from current exposure to
lead pursuant to paragraph (k) of this section.
(ii) Each record shall include:
(A) The name and social security number of the employee;
(B) The date on each occasion that the employee was removed from
current exposure to lead as well as the corresponding date on which the
employee was returned to his or her former job status;
(C) A brief explanation of how each removal was or is being
accomplished; and
(D) A statement with respect to each removal indicating whether or
not the reason for the removal was an elevated blood lead level.
(iii) The employer shall maintain each medical removal record for at
least the duration of an employee's employment.
(4) Availability. (i) The employer shall make available upon request
all records required to be maintained by paragraph (n) of this section
to the Assistant Secretary and the Director for examination and copying.
(ii) Environmental monitoring, medical removal, and medical records
required by this paragraph shall be provided upon request to employees,
designated representatives, and the Assistant Secretary in accordance
with 29 CFR 1910.20 (a)-(e) and (2)-(i). Medical removal records shall
be provided in the same manner as environmental monitoring records.
(5) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by paragraph (n) of this section.
(ii) Whenever the employer ceases to do business and there is no
successor employer to receive and retain the records required to be
maintained by this section for the prescribed period, these records
shall be transmitted to the Director.
(iii) At the expiration of the retention period for the records
required to be maintained by this section, the employer shall notify the
Director at least 3 months prior to the disposal of such records and
shall transmit those records to the Director if requested within the
period.
(iv) The employer shall also comply with any additional requirements
involving transfer of records set forth in 29 CFR 1910.20(h).
(o) Observation of monitoring. (1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to lead conducted pursuant to paragraph (d) of this section.
(2) Observation procedures. (i) Whenever observation of the
monitoring of employee exposure to lead requires entry into an area
where the use of respirators, protective clothing or equipment is
required, the employer shall provide the observer with and assure the
use of such respirators, clothing and such equipment, and shall require
the observer to comply with all other applicable safety and health
procedures.
(ii) Without interfering with the monitoring, observers shall be
entitled to:
(A) Receive an explanation of the measurement procedures;
(B) Observe all steps related to the monitoring of lead performed at
the place of exposure; and
(C) Record the results obtained or receive copies of the results
when returned by the laboratory.
(p) Effective date. This standard shall become effective March 1,
1979.
(q) Appendices. The information contained in the appendices to this
section is not intended by itself, to create any additional obligations
not otherwise imposed by this standard nor detract from any existing
obligation.
(r) Startup dates. All obligations of this standard commence on the
effective date except as follows:
(1) The initial determination under paragraph (d)(2) shall be made
as soon
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as possible but no later than 30 days from the effective date.
(2) Initial monitoring under paragraph (d)(4) shall be completed as
soon as possible but no later than 90 days from the effective date.
(3) Initial biological monitoring and medical examinations under
paragraph (j) shall be completed as soon as possible but no later than
180 days from the effective date. Priority for biological monitoring and
medical examinations shall be given to employees whom the employer
believes to be at greatest risk from continued exposure.
(4) Initial training and education shall be completed as soon as
possible but no later than 180 days from the effective date.
(5) Hygiene and lunchroom facilities under paragraph (i) shall be in
operation as soon as possible but no later than 1 year from the
effective year.
(6)(i) Respiratory protection required by paragraph (f) shall be
provided as soon as possible but no later than the following schedule:
(A) Employees whose 8-hour TWA exposure exceeds 200 g/
m3--on the effective date.
(B) Employees whose 8-hour TWA exposure exceeds the PEL but is less
than 200 g/m3--150 days from the effective date.
(C) Powered, air-purifying respirators provided under (f)(2)(ii)--
210 days from the effective date.
(D) Quantitative fit testing required under (f)(3)(ii)--one year
from effective date. Qualitative fit testing is required in the interim.
(7)(i) Written compliance plans required by paragraph (e)(3) shall
be completed and available for inspection and copying as soon as
possible but no later than the following schedule:
(A) Employers for whom compliance with the PEL or interim level is
required within 1 year from the effective date--6 months from the
effective date.
(B) Employers in secondary lead smelting and refining and in lead
storage battery manufacturing--1 year from the effective date.
(C) Employers in primary smelting and refining industry--1 year from
the effective date for the interim level; 5 years from the effective
date for PEL.
(D) Plans for construction of hygiene facilities, if required--6
months from the effective date.
(E) All other industries--1 year from the date on which the court
lifts the stay on the implementation of paragraph (e)(1) for the
particular industry.
(8) The permissible exposure limit in paragraph (c) shall become
effective 150 days from the effective date.
Appendix A to Sec. 1910.1025--Substance Data Sheet for Occupational
Exposure to Lead
i. Substance Identification
A. Substance: Pure lead (Pb) is a heavy metal at room temperature
and pressure and is a basic chemical element. It can combine with
various other substances to form numerous lead compounds.
B. Compounds Covered by the Standard: The word ``lead'' when used in
this standard means elemental lead, all inorganic lead compounds and a
class of organic lead compounds called lead soaps. This standard does
not apply to other organic lead compounds.
C. Uses: Exposure to lead occurs in at least 120 different
occupations, including primary and secondary lead smelting, lead storage
battery manufacturing, lead pigment manufacturing and use, solder
manufacturing and use, shipbuilding and ship repairing, auto
manufacturing, and printing.
D. Permissible Exposure: The Permissible Exposure Limit (PEL) set by
the standard is 50 micrograms of lead per cubic meter of air (50
g/m3), averaged over an 8-hour workday.
E. Action Level: The standard establishes an action level of 30
micrograms per cubic meter of air (30 g/m3), time
weighted average, based on an 8-hour work-day. The action level
initiates several requirements of the standard, such as exposure
monitoring, medical surveillance, and training and education.
ii. health hazard data
A. Ways in which lead enters your body. When absorbed into your body
in certain doses lead is a toxic substance. The object of the lead
standard is to prevent absorption of harmful quantities of lead. The
standard is intended to protect you not only from the immediate toxic
effects of lead, but also from the serious toxic effects that may not
become apparent until years of exposure have passed.
Lead can be absorbed into your body by inhalation (breathing) and
ingestion (eating). Lead (except for certain organic lead compounds not
covered by the standard, such as tetraethyl lead) is not absorbed
through your skin. When lead is scattered in the air as a dust, fume or
mist it can be inhaled and
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absorbed through you lungs and upper respiratory tract. Inhalation of
airborne lead is generally the most important source of occupational
lead absorption. You can also absorb lead through your digestive system
if lead gets into your mouth and is swallowed. If you handle food,
cigarettes, chewing tobacco, or make-up which have lead on them or
handle them with hands contaminated with lead, this will contribute to
ingestion.
A significant portion of the lead that you inhale or ingest gets
into your blood stream. Once in your blood stream, lead is circulated
throughout your body and stored in various organs and body tissues. Some
of this lead is quickly filtered out of your body and excreted, but some
remains in the blood and other tissues. As exposure to lead continues,
the amount stored in your body will increase if you are absorbing more
lead than your body is excreting. Even though you may not be aware of
any immediate symptoms of disease, this lead stored in your tissues can
be slowly causing irreversible damage, first to individual cells, then
to your organs and whole body systems.
B. Effects of overexposure to lead--(1) Short term (acute)
overexposure. Lead is a potent, systemic poison that serves no known
useful function once absorbed by your body. Taken in large enough doses,
lead can kill you in a matter of days. A condition affecting the brain
called acute encephalopathy may arise which develops quickly to
seizures, coma, and death from cardiorespiratory arrest. A short term
dose of lead can lead to acute encephalopathy. Short term occupational
exposures of this magnitude are highly unusual, but not impossible.
Similar forms of encephalopathy may, however, arise from extended,
chronic exposure to lower doses of lead. There is no sharp dividing line
between rapidly developing acute effects of lead, and chronic effects
which take longer to acquire. Lead adversely affects numerous body
systems, and causes forms of health impairment and disease which arise
after periods of exposure as short as days or as long as several years.
(2) Long-term (chronic) overexposure. Chronic overexposure to lead
may result in severe damage to your blood-forming, nervous, urinary and
reproductive systems. Some common symptoms of chronic overexposure
include loss of appetite, metallic taste in the mouth, anxiety,
constipation, nausea, pallor, excessive tiredness, weakness, insomnia,
headache, nervous irritability, muscle and joint pain or soreness, fine
tremors, numbness, dizziness, hyperactivity and colic. In lead colic
there may be severe abdominal pain.
Damage to the central nervous system in general and the brain
(encephalopathy) in particular is one of the most severe forms of lead
poisoning. The most severe, often fatal, form of encephalopathy may be
preceded by vomiting, a feeling of dullness progressing to drowsiness
and stupor, poor memory, restlessness, irritability, tremor, and
convulsions. It may arise suddenly with the onset of seizures, followed
by coma, and death. There is a tendency for muscular weakness to develop
at the same time. This weakness may progress to paralysis often observed
as a characteristic ``wrist drop'' or ``foot drop'' and is a
manifestation of a disease to the nervous system called peripheral
neuropathy.
Chronic overexposure to lead also results in kidney disease with
few, if any, symptoms appearing until extensive and most likely
permanent kidney damage has occurred. Routine laboratory tests reveal
the presence of this kidney disease only after about two-thirds of
kidney function is lost. When overt symptoms of urinary dysfunction
arise, it is often too late to correct or prevent worsening conditions,
and progression to kidney dialysis or death is possible.
Chronic overexposure to lead impairs the reproductive systems of
both men and women. Overexposure to lead may result in decreased sex
drive, impotence and sterility in men. Lead can alter the structure of
sperm cells raising the risk of birth defects. There is evidence of
miscarriage and stillbirth in women whose husbands were exposed to lead
or who were exposed to lead themselves. Lead exposure also may result in
decreased fertility, and abnormal menstrual cycles in women. The course
of pregnancy may be adversely affected by exposure to lead since lead
crosses the placental barrier and poses risks to developing fetuses.
Children born of parents either one of whom were exposed to excess lead
levels are more likely to have birth defects, mental retardation,
behavioral disorders or die during the first year of childhood.
Overexposure to lead also disrupts the blood-forming system
resulting in decreased hemoglobin (the substance in the blood that
carries oxygen to the cells) and ultimately anemia. Anemia is
characterized by weakness, pallor and fatigability as a result of
decreased oxygen carrying capacity in the blood.
(3) Health protection goals of the standard. Prevention of adverse
health effects for most workers from exposure to lead throughout a
working lifetime requires that worker blood lead (PbB) levels be
maintained at or below forty micrograms per one hundred grams of whole
blood (40 g/100g). The blood lead levels of workers (both male
and female workers) who intend to have children should be maintained
below 30 g/100g to minimize adverse reproductive health effects
to the parents and to the developing fetus.
The measurement of your blood lead level is the most useful
indicator of the amount of lead being absorbed by your body. Blood lead
levels (PbB) are most often reported in units
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of milligrams (mg) or micrograms (g) of lead (1 mg=1000
g) per 100 grams (100g), 100 milliters (100 ml) or deciliter
(dl) of blood. These three units are essentially the same. Sometime
PbB's are expressed in the form of mg% or g%. This is a
shorthand notation for 100g, 100 ml, or dl.
PbB measurements show the amount of lead circulating in your blood
stream, but do not give any information about the amount of lead stored
in your various tissues. PbB measurements merely show current absorption
of lead, not the effect that lead is having on your body or the effects
that past lead exposure may have already caused. Past research into
lead-related diseases, however, has focused heavily on associations
between PbBs and various diseases. As a result, your PbB is an important
indicator of the likelihood that you will gradually acquire a lead-
related health impairment or disease.
Once your blood lead level climbs above 40 g/100g, your
risk of disease increases. There is a wide variability of individual
response to lead, thus it is difficult to say that a particular PbB in a
given person will cause a particular effect. Studies have associated
fatal encephalopathy with PbBs as low as 150 g/100g. Other
studies have shown other forms of diseases in some workers with PbBs
well below 80 g/100g. Your PbB is a crucial indicator of the
risks to your health, but one other factor is also extremely important.
This factor is the length of time you have had elevated PbBs. The longer
you have an elevated PbB, the greater the risk that large quantities of
lead are being gradually stored in your organs and tissues (body
burden). The greater your overall body burden, the greater the chances
of substantial permanent damage.
The best way to prevent all forms of lead-related impairments and
diseases--both short term and long term- is to maintain your PbB below
40 g/100g. The provisions of the standard are designed with
this end in mind. Your employer has prime responsibility to assure that
the provisions of the standard are complied with both by the company and
by individual workers. You as a worker, however, also have a
responsibility to assist your employer in complying with the standard.
You can play a key role in protecting your own health by learning about
the lead hazards and their control, learning what the standard requires,
following the standard where it governs your own actions, and seeing
that your employer complies with provisions governing his actions.
(4) Reporting signs and symptoms of health problems. You should
immediately notify your employer if you develop signs or symptoms
associated with lead poisoning or if you desire medical advice
concerning the effects of current or past exposure to lead on your
ability to have a healthy child. You should also notify your employer if
you have difficulty breathing during a respirator fit test or while
wearing a respirator. In each of these cases your employer must make
available to you appropriate medical examinations or consultations.
These must be provided at no cost to you and at a reasonable time and
place.
The standard contains a procedure whereby you can obtain a second
opinion by a physician of your choice if the employer selected the
initial physician.
Appendix B to Sec. 1910.1025--Employee Standard Summary
This appendix summarizes key provisions of the standard that you as
a worker should become familiar with.
i. Permissible Exposure Limit (pel)--Paragraph (c)
The standards sets a permissible exposure limit (PEL) of fifty
micrograms of lead per cubic meter of air (50 g/m3),
averaged over an 8-hour work-day. This is the highest level of lead in
air to which you may be permissibly exposed over an 8-hour workday.
Since it is an 8-hour average it permits short exposures above the PEL
so long as for each 8-hour work day your average exposure does not
exceed the PEL.
This standard recognizes that your daily exposure to lead can extend
beyond a typical 8-hour workday as the result of overtime or other
alterations in your work schedule. To deal with this, the standard
contains a formula which reduces your permissible exposure when you are
exposed more than 8 hours. For example, if you are exposed to lead for
10 hours a day, the maximum permitted average exposure would be 40
g/m3.
ii. exposure monitoring--paragraph (d)
If lead is present in the workplace where you work in any quantity,
your employer is required to make an initial determination of whether
the action level is exceeded for any employee. This initial
determination must include instrument monitoring of the air for the
presence of lead and must cover the exposure of a representative number
of employees who are reasonably believed to have the highest exposure
levels. If your employer has conducted appropriate air sampling for lead
in the past year he may use these results. If there have been any
employee complaints of symptoms which may be attributable to exposure to
lead or if there is any other information or observations which would
indicate employee exposure to lead, this must also be considered as part
of the initial determination. This initial determination must have been
completed by March 31, 1979. If this initial determination shows that a
reasonable possibility exists that any employee may be exposed, without
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regard to respirators, over the action level (30 g/
m3) your employer must set up an air monitoring program to
determine the exposure level of every employee exposed to lead at your
workplace.
In carrying out this air monitoring program, your employer is not
required to monitor the exposure of every employee, but he must monitor
a representative number of employees and job types. Enough sampling must
be done to enable each employee's exposure level to be reasonably least
one full shift (at least 7 hours) air sample. In addition, these air
samples must be taken under conditions which represent each employee's
regular, daily exposure to lead. All initial exposure monitoring must
have been completed by May 30, 1979.
If you are exposed to lead and air sampling is performed, your
employer is required to quickly notify you in writing of air monitoring
results which represent your exposure. If the results indicate your
exposure exceeds the PEL (without regard to your use of respirators),
then your employer must also notify you of this in writing, and provide
you with a description of the corrective action that will be taken to
reduce your exposure.
Your exposure must be rechecked by monitoring every six months if
your exposure is over the action level but below the PEL. Air monitoring
must be repeated every 3 months if you are exposed over the PEL. Your
employer may discontinue monitoring for you if 2 consecutive
measurements, taken at least two weeks apart, are below the action
level. However, whenever there is a production, process, control, or
personnel change at your workplace which may result in new or additional
exposure to lead, or whenever there is any other reason to suspect a
change which may result in new or additional exposure to lead, your
employer must perform additional monitoring.
iii. methods of compliance--paragraph (e)
Your employer is required to assure that no employee is exposed to
lead in excess of the PEL. The standard establishes a priority of
methods to be used to meet the PEL.
iv. respiratory protection--paragraph (f)
Your employer is required to provide and assure your use of
respirators when your exposure to lead is not controlled below the PEL
by other means. The employer must pay the cost of the respirator.
Whenever you request one, your employer is also required to provide you
a respirator even if your air exposure level does not exceed the PEL.
You might desire a respirator when, for example, you have received
medical advice that your lead absorption should be decreased. Or, you
may intend to have children in the near future, and want to reduce the
level of lead in your body to minimize adverse reproductive effects.
While respirators are the least satisfactory means of controlling your
exposure, they are capable of providing significant protection if
properly chosen, fitted, worn, cleaned, maintained, and replaced when
they stop providing adequate protection.
Your employer is required to select respirators from the seven types
listed in Table II of the Respiratory Protection section of the standard
(Sec. 1910.1025(f)). Any respirator chosen must be approved by the
National Institute for Occupational Safety and Health (NIOSH) under the
provisions of 42 CFR part 84. This respirator selection table will
enable your employer to choose a type of respirator that will give you a
proper amount of protection based on your airborne lead exposure. Your
employer may select a type of respirator that provides greater
protection than that required by the standard; that is, one recommended
for a higher concentration of lead than is present in your workplace.
For example, a powered air-purifying respirator (PAPR) is much more
protective than a typical negative pressure respirator, and may also be
more comfortable to wear. A PAPR has a filter, cartridge, or canister to
clean the air, and a power source that continuously blows filtered air
into your breathing zone. Your employer might make a PAPR available to
you to ease the burden of having to wear a respirator for long periods
of time. The standard provides that you can obtain a PAPR upon request.
Your employer must also start a Respiratory Protection Program. This
program must include written procedures for the proper selection, use,
cleaning, storage, and maintenance of respirators.
Your employer must ensure that your respirator facepiece fits
properly. Proper fit of a respirator facepiece is critical to your
protection from airborne lead. Obtaining a proper fit on each employee
may require your employer to make available several different types of
respirator masks. To ensure that your respirator fits properly and that
facepiece leakage is minimal, your employer must give you either a
qualitative or quantitative fit test as specified in Appendix A of the
Respiratory Protection standard located at 29 CFR 1910.134.
You must also receive from your employer proper training in the use
of respirators. Your employer is required to teach you how to wear a
respirator, to know why it is needed, and to understand its limitations.
The standard provides that if your respirator uses filter elements,
you must be given an opportunity to change the filter elements whenever
an increase in breathing resistance is detected. You also must be
permitted to periodically leave your work area to wash your face and
respirator facepiece whenever necessary to prevent skin irritation. If
you ever have difficulty in breathing
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during a fit test or while using a respirator, your employer must make a
medical examination available to you to determine whether you can safely
wear a respirator. The result of this examination may be to give you a
positive pressure respirator (which reduces breathing resistance) or to
provide alternative means of protection.
v. protective work clothing and equipment--paragraph (g)
If you are exposed to lead above the PEL, or if you are exposed to
lead compounds such as lead arsenate or lead azide which can cause skin
and eye irritation, your employer must provide you with protective work
clothing and equipment appropriate for the hazard. If work clothing is
provided, it must be provided in a clean and dry condition at least
weekly, and daily if your airborne exposure to lead is greater than 200
g/m3. Appropriate protective work clothing and
equipment can include coveralls or similar full-body work clothing,
gloves, hats, shoes or disposable shoe coverlets, and face shields or
vented goggles. Your employer is required to provide all such equipment
at no cost to you. He is responsible for providing repairs and
replacement as necessary, and also is responsible for the cleaning,
laundering or disposal of protective clothing and equipment.
Contaminated work clothing or equipment must be removed in change rooms
and not worn home or you will extend your exposure and expose your
family since lead from your clothing can accumulate in your house, car,
etc. Contaminated clothing which is to be cleaned, laundered or disposed
of must be placed in closed containers in the change room. At no time
may lead be removed from protective clothing or equipment by any means
which disperses lead into the workroom air.
vi. housekeeping--paragraph (h)
Your employer must establish a housekeeping program sufficient to
maintain all surfaces as free as practicable of accumulations of lead
dust. Vacuuming is the preferred method of meeting this requirement, and
the use of compressed air to clean floors and other surfaces is
absolutely prohibited. Dry or wet sweeping, shoveling, or brushing may
not be used except where vaccuming or other equally effective methods
have been tried and do not work. Vacuums must be used and emptied in a
manner which minimizes the reentry of lead into the workplace.
vii. hygiene facilities and practices--paragraph (i)
The standard requires that change rooms, showers, and filtered air
lunchrooms be constructed and made available to workers exposed to lead
above the PEL. When the PEL is exceeded the employer must assure that
food and beverage is not present or consumed, tobacco products are not
present or used, and cosmetics are not applied, except in these
facilities. Change rooms, showers, and lunchrooms, must be used by
workers exposed in excess of the PEL. After showering, no clothing or
equipment worn during the shift may be worn home, and this includes
shoes and underwear. Your own clothing worn during the shift should be
carried home and cleaned carefully so that it does not contaminate your
home. Lunchrooms may not be entered with protective clothing or
equipment unless surface dust has been removed by vacuuming, downdraft
booth, or other cleaning method. Finally, workers exposed above the PEL
must wash both their hands and faces prior to eating, drinking, smoking
or applying cosmetics.
All of the facilities and hygiene practices just discussed are
essential to minimize additional sources of lead absorption from
inhalation or ingestion of lead that may accumulate on you, your
clothes, or your possessions. Strict compliance with these provisions
can virtually eliminate several sources of lead exposure which
significantly contribute to excessive lead absorption.
viii. medical surveillance--paragraph (j)
The medical surveillance program is part of the standard's
comprehensive approach to the prevention of lead-related disease. Its
purpose is to supplement the main thrust of the standard which is aimed
at minimizing airborne concentrations of lead and sources of ingestion.
Only medical surveillance can determine if the other provisions of the
standard have affectively protected you as an individual. Compliance
with the standard's provision will protect most workers from the adverse
effects of lead exposure, but may not be satisfactory to protect
individual workers (1) who have high body burdens of lead acquired over
past years, (2) who have additional uncontrolled sources of non-
occupational lead exposure, (3) who exhibit unusual variations in lead
absorption rates, or (4) who have specific non-work related medical
conditions which could be aggravated by lead exposure (e.g., renal
disease, anemia). In addition, control systems may fail, or hygiene and
respirator programs may be inadequate. Periodic medical surveillance of
individual workers will help detect those failures. Medical surveillance
will also be important to protect your reproductive ability--regardless
of whether you are a man or woman.
All medical surveillance required by the standard must be performed
by or under the supervision of a licensed physician. The employer must
provide required medical surveillance without cost to employees and at a
reasonable time and place. The standard's medical surveillance program
has two parts-
[[Page 122]]
periodic biological monitoring and medical examinations.
Your employer's obligation to offer you medical surveillance is
triggered by the results of the air monitoring program. Medical
surveillance must be made available to all employees who are exposed in
excess of the action level for more than 30 days a year. The initial
phase of the medical surveillance program, which includes blood lead
level tests and medical examinations, must be completed for all covered
employees no later than August 28, 1979. Priority within this first
round of medical surveillance must be given to employees whom the
employer believes to be at greatest risk from continued exposure (for
example, those with the longest prior exposure to lead, or those with
the highest current exposure). Thereafter, the employer must
periodically make medical surveillance--both biological monitoring and
medical examinations--available to all covered employees.
Biological monitoring under the standard consists of blood lead
level (PbB) and zinc protoporphyrin tests at least every 6 months after
the initial PbB test. A zinc protoporphyrin (ZPP) test is a very useful
blood test which measures an effect of lead on your body. Thus
biological monitoring under the standard is currently limited to PbB
testing. If a worker's PbB exceeds 40 g/100g the monitoring
frequency must be increased from every 6 months to at least every 2
months and not reduced until two consecutive PbBs indicate a blood lead
level below 40 g/100g. Each time your PbB is determined to be
over 40 g/100g, your employer must notify you of this in
writing within five working days of his receipt of the test results. The
employer must also inform you that the standard requires temporary
medical removal with economic protection when your PbB exceeds certain
criteria. (See Discussion of Medical Removal Protection--Paragraph (k).)
During the first year of the standard, this removal criterion is 80
g/100g. Anytime your PbB exceeds 80 g/100g your
employer must make available to you a prompt follow-up PbB test to
ascertain your PbB. If the two tests both exceed 80 g/100g and
you are temporarily removed, then your employer must make successive PbB
tests available to you on a monthly basis during the period of your
removal.
Medical examinations beyond the initial one must be made available
on an annual basis if your blood lead level exceeds 40 g/100g
at any time during the preceding year. The initial examination will
provide information to establish a baseline to which subsequent data can
be compared. An initial medical examination must also be made available
(prior to assignment) for each employee being assigned for the first
time to an area where the airborne concentration of lead equals or
exceeds the action level. In addition, a medical examination or
consultation must be made available as soon as possible if you notify
your employer that you are experiencing signs or symptoms commonly
associated with lead poisoning or that you have difficulty breathing
while wearing a respirator or during a respirator fit test. You must
also be provided a medical examination or consultation if you notify
your employer that you desire medical advice concerning the effects of
current or past exposure to lead on your ability to procreate a healthy
child.
Finally, appropriate follow-up medical examinations or consultations
may also be provided for employees who have been temporarily removed
from exposure under the medical removal protection provisions of the
standard. (See Part IX, below.)
The standard specifies the minimum content of pre-assignment and
annual medical examinations. The content of other types of medical
examinations and consultations is left up to the sound discretion of the
examining physician. Pre-assignment and annual medical examinations must
include (1) a detailed work history and medical history, (2) a thorough
physical examination, and (3) a series of laboratory tests designed to
check your blood chemistry and your kidney function. In addition, at any
time upon your request, a laboratory evaluation of male fertility will
be made (microscopic examination of a sperm sample), or a pregnancy test
will be given.
The standard does not require that you participate in any of the
medical procedures, tests, etc. which your employer is required to make
available to you. Medical surveillance can, however, play a very
important role in protecting your health. You are strongly encouraged,
therefore, to participate in a meaningful fashion. The standard contains
a multiple physician review mechanism which would give you a chance to
have a physician of your choice directly participate in the medical
surveillance program. If you were dissatisfied with an examination by a
physician chosen by your employer, you could select a second physician
to conduct an independent analysis. The two doctors would attempt to
resolve any differences of opinion, and select a third physician to
resolve any firm dispute. Generally your employer will choose the
physician who conducts medical surveillance under the lead standard--
unless you and your employer can agree on the choice of a physician or
physicians. Some companies and unions have agreed in advance, for
example, to use certain independent medical laboratories or panels of
physicians. Any of these arrangements are acceptable so long as required
medical surveillance is made available to workers.
The standard requires your employer to provide certain information
to a physician to
[[Page 123]]
aid in his or her examination of you. This information includes (1) the
standard and its appendices, (2) a description of your duties as they
relate to lead exposure, (3) your exposure level, (4) a description of
personal protective equipment you wear, (5) prior blood lead level
results, and (6) prior written medical opinions concerning you that the
employer has. After a medical examination or consultation the physician
must prepare a written report which must contain (1) the physician's
opinion as to whether you have any medical condition which places you at
increased risk of material impairment to health from exposure to lead,
(2) any recommended special protective measures to be provided to you,
(3) any blood lead level determinations, and (4) any recommended
limitation on your use of respirators. This last element must include a
determination of whether you can wear a powered air purifying respirator
(PAPR) if you are found unable to wear a negative pressure respirator.
The medical surveillance program of the lead standard may at some
point in time serve to notify certain workers that they have acquired a
disease or other adverse medical condition as a result of occupational
lead exposure. If this is true, these workers might have legal rights to
compensation from public agencies, their employers, firms that supply
hazardous products to their employers, or other persons. Some states
have laws, including worker compensation laws, that disallow a worker
who learns of a job-related health impairment to sue, unless the worker
sues within a short period of time after learning of the impairment.
(This period of time may be a matter of months or years.) An attorney
can be consulted about these possibilities. It should be stressed that
OSHA is in no way trying to either encourage or discourage claims or
lawsuits. However, since results of the standard's medical surveillance
program can significantly affect the legal remedies of a worker who has
acquired a job-related disease or impairment, it is proper for OSHA to
make you aware of this.
The medical surveillance section of the standard also contains
provisions dealing with chelation. Chelation is the use of certain drugs
(administered in pill form or injected into the body) to reduce the
amount of lead absorbed in body tissues. Experience accumulated by the
medical and scientific communities has largely confirmed the
effectiveness of this type of therapy for the treatment of very severe
lead poisoning. On the other hand, it has also been established that
there can be a long list of extremely harmful side effects associated
with the use of chelating agents. The medical community has balanced the
advantages and disadvantages resulting from the use of chelating agents
in various circumstances and has established when the use of these
agents is acceptable. The standard includes these accepted limitations
due to a history of abuse of chelation therapy by some lead companies.
The most widely used chelating agents are calcium disodium EDTA, (Ca
Na2 EDTA), Calcium Disodium Versenate (Versenate), and d-
penicillamine (pencillamine or Cupramine).
The standard prohibits ``prophylactic chelation'' of any employee by
any person the employer retains, supervises or controls. ``Prophylactic
chelation'' is the routine use of chelating or similarly acting drugs to
prevent elevated blood levels in workers who are occupationally exposed
to lead, or the use of these drugs to routinely lower blood lead levels
to predesignated concentrations believed to be `safe'. It should be
emphasized that where an employer takes a worker who has no symptoms of
lead poisoning and has chelation carried out by a physician (either
inside or outside of a hospital) solely to reduce the worker's blood
lead level, that will generally be considered prophylactic chelation.
The use of a hospital and a physician does not mean that prophylactic
chelation is not being performed. Routine chelation to prevent increased
or reduce current blood lead levels is unacceptable whatever the
setting.
The standard allows the use of ``therapeutic'' or ``diagnostic''
chelation if administered under the supervision of a licensed physician
in a clinical setting with thorough and appropriate medical monitoring.
Therapeutic chelation responds to severe lead poisoning where there are
marked symptoms. Diagnostic chelation involved giving a patient a dose
of the drug then collecting all urine excreted for some period of time
as an aid to the diagnosis of lead poisoning.
In cases where the examining physician determines that chelation is
appropriate, you must be notified in writing of this fact before such
treatment. This will inform you of a potentially harmful treatment, and
allow you to obtain a second opinion.
ix. medical removal protection--paragraph (k)
Excessive lead absorption subjects you to increased risk of disease.
Medical removal protection (MRP) is a means of protecting you when, for
whatever reasons, other methods, such as engineering controls, work
practices, and respirators, have failed to provide the protection you
need. MRP involves the temproary removal of a worker from his or her
regular job to a place of significantly lower exposure without any loss
of earnings, seniority, or other employment rights or benefits. The
purpose of this program is to cease further lead absorption and allow
your body to naturally excrete lead which has previously been absorbed.
Temporary medical removal can result from an elevated blood lead level,
or a medical opinion. Up to 18 months of protection is provided as a
result
[[Page 124]]
of either form of removal. The vast majority of removed workers,
however, will return to their former jobs long before this eighteen
month period expires. The standard contains special provisions to deal
with the extraordinary but possible case where a longterm worker's blood
lead level does not adequately decline during eighteen months of
removal.
During the first year of the standard, if your blood lead level is
80 g/100g or above you must be removed from any exposure where
your air lead level without a respirator would be 100 g/
m3or above. If you are removed from your normal job you may
not be returned until your blood lead level declines to at least 60
g/100g. These criteria for removal and return will change
according to the following schedule:
----------------------------------------------------------------------------------------------------------------
Removal blood lead Air lead (g/ Return blood lead
(g/100 g) m3) (g/100 g)
----------------------------------------------------------------------------------------------------------------
After Mar. 1, 1980................... 70 and above........... 50 and above........... At or below 50.
After Mar. 1, 1981................... 60 and above........... 30 and above........... At or below 40.
After Mar. 1, 1983................... 50 and above averaged 30 and above........... Do.
over six months.
----------------------------------------------------------------------------------------------------------------
You may also be removed from exposure even if your blood lead levels
are below these criteria if a final medical determination indicates that
you temporarily need reduced lead exposure for medical reasons. If the
physician who is implementing your employers medical program makes a
final written opinion recommending your removal or other special
protective measures, your employer must implement the physician's
recommendation. If you are removed in this manner, you may only be
returned when the doctor indicates that it is safe for you to do so.
The standard does not give specific instructions dealing with what
an employer must do with a removed worker. Your job assignment upon
removal is a matter for you, your employer and your union (if any) to
work out consistent with existing procedures for job assignments. Each
removal must be accomplished in a manner consistent with existing
collective bargaining relationships. Your employer is given broad
discretion to implement temporary removals so long as no attempt is made
to override existing agreements. Similarly, a removed worker is provided
no right to veto an employer's choice which satisfies the standard.
In most cases, employers will likely transfer removed employees to
other jobs with sufficiently low lead exposure. Alternatively, a
worker's hours may be reduced so that the time weighted average exposure
is reduced, or he or she may be temporarily laid off if no other
alternative is feasible.
In all of these situation, MRP benefits must be provided during the
period of removal--i.e., you continue to receive the same earnings,
seniority, and other rights and benefits you would have had if you had
not been removed. Earnings includes more than just your base wage; it
includes overtime, shift differentials, incentives, and other
compensation you would have earned if you had not been removed. During
the period of removal you must also be provided with appropriate follow-
up medical surveillance. If you were removed because your blood lead
level was too high, you must be provided with a monthly blood test. If a
medical opinion caused your removal, you must be provided medical tests
or examinations that the doctor believes to be appropriate. If you do
not participate in this follow up medical surveillance, you may lose
your eligibility for MRP benefits.
When you are medically eligible to return to your former job, your
employer must return you to your ``former job status.'' This means that
you are entitled to the position, wages, benefits, etc., you would have
had if you had not been removed. If you would still be in your old job
if no removal had occurred that is where you go back. If not, you are
returned consistent with whatever job assignment discretion your
employer would have had if no removal had occurred. MRP only seeks to
maintain your rights, not expand them or diminish them.
If you are removed under MRP and you are also eligible for worker
compensation or other compensation for lost wages, your employer's MRP
benefits obligation is reduced by the amount that you actually receive
from these other sources. This is also true if you obtain other
employment during the time you are laid off with MRP benefits.
The standard also covers situations where an employer voluntarily
removes a worker from exposure to lead due to the effects of lead on the
employee's medical condition, even though the standard does not require
removal. In these situations MRP benefits must still be provided as
though the standard required removal. Finally, it is important to note
that in all cases where removal is required, respirators cannot be used
as a substitute. Respirators may be used before removal becomes
necessary, but not as an alternative to a transfer to a low exposure
job, or to a lay-off with MRP benefits.
[[Page 125]]
x. employee information and training--paragraph (l)
Your employer is required to provide an information and training
program for all employees exposed to lead above the action level or who
may suffer skin or eye irritation from lead. This program must inform
these employees of the specific hazards associated with their work
environment, protective measures which can be taken, the danger of lead
to their bodies (including their reproductive systems), and their rights
under the standard. In addition your employer must make readily
available to all employees, including those exposed below the action
level, a copy of the standard and its appendices and must distribute to
all employees any materials provided to the employer by the Occupational
Safety and Health Administration (OSHA).
Your employer is required to complete this training program for all
employees by August 28, 1979. After this date, all new employees must be
trained prior to initial assignment to areas where there is a
possibility of exposure over the action level.
This training program must also be provided at least annually
thereafter.
xi. signs--paragraph (m)
The standard requires that the following warning sign be posted in
work areas where the exposure to lead exceeds the PEL:
WARNING
LEAD WORK AREA
NO SMOKING OR EATING
xii. recordkeeping--paragraph (n)
Your employer is required to keep all records of exposure monitoring
for airborne lead. These records must include the name and job
classification of employees measured, details of the sampling and
analytic techniques, the results of this sampling, and the type of
respiratory protection being worn by the person sampled. Your employer
is also required to keep all records of biological monitoring and
medical examination results. These must include the names of the
employees, the physician's written opinion, and a copy of the results of
the examination. All of the above kinds of records must be kept for 40
years, or for at least 20 years after your termination of employment,
whichever is longer.
Recordkeeping is also required if you are temporarily removed from
your job under the medical removal protection program. This record must
include your name and social security number, the date of your removal
and return, how the removal was or is being accomplished, and whether or
not the reason for the removal was an elevated blood lead level. Your
employer is required to keep each medical removal record only for as
long as the duration of an employee's employment.
The standard requires that if you request to see or copy
environmental monitoring, blood lead level monitoring, or medical
removal records, they must be made available to you or to a
representative that you authorize. Your union also has access to these
records. Medical records other than PbB's must also be provided upon
request to you, to your physician or to any other person whom you may
specifically designate. Your union does not have access to your personal
medical records unless you authorize their access.
xiii. observations of monitoring--paragraph (o)
When air monitoring for lead is performed at your workplace as
required by this standard, your employer must allow you or someone you
designate to act as an observer of the monitoring. Observers are
entitled to an explanation of the measurement procedure, and to record
the results obtained. Since results will not normally be available at
the time of the monitoring, observers are entitled to record or receive
the results of the monitoring when returned by the laboratory. Your
employer is required to provide the observer with any personal
protective devices required to be worn by employees working in the area
that is being monitored. The employer must require the observer to wear
all such equipment and to comply with all other applicable safety and
health procedures.
xiv. effective date--paragraph (p)
The standard's effective data is March 1, 1979, and employer
obligations under the standard begin to come into effect as of that
date.
xv. for additional information
A. Copies of the Standard and explanatory material may be obtained
by writing or calling the OSHA Docket Office, U.S. Department of Labor,
room N2634, 200 Constitution Avenue, N.W., Washington, DC 20210.
Telephone: (202) 219-7894.
1. The standard and summary of the statement of reasons (preamble),
Federal Register, Volume 43, pp. 52952-53014, November 14, 1978.
2. The full statement of reasons (preamble) Federal Register, vol.
43, pp. 54354-54509, November 21, 1978.
3. Partial Administrative Stay and Corrections to the standard, (44
FR 5446-5448) January 26, 1979.
4. Notice of the Partial Judicial Stay (44 FR 14554-14555) March 13,
1979.
5. Corrections to the preamble, Federal Register, vol. 44, pp.
20680-20681, April 6, 1979.
[[Page 126]]
6. Additional correction to the preamble concerning the construction
industry, Federal Register, vol. 44, p. 50338, August 28, 1979.
7. Appendices to the standard (Appendices A, B, C), Federal
Register, Vol. 44, pp. 60980-60995, October 23, 1979.
8. Corrections to appendices, Federal Register, Vol. 44, 68828,
November 30, 1979.
9. Revision to the standard and an additional appendix (Appendix D),
Federal Register, Vol. 47, pp. 51117-51119, November 12, 1982.
10. Notice of reopening of lead rulemaking for nine remand industry
sectors, Federal Register, vol. 53, pp. 11511-11513, April 7, 1988.
11. Statement of reasons, Federal Register, vol. 54, pp. 29142-
29275, July 11, 1989.
12. Statement of reasons, Federal Register, vol. 55, pp. 3146-3167,
January 30, 1990.
13. Correction to appendix B, Federal Register, vol. 55, pp. 4998-
4999, February 13, 1991.
14. Correction to appendices, Federal Register, vol. 56, p. 24686,
May 31, 1991.
B. Additional information about the standard, its enforcement, and
your employer's compliance can be obtained from the nearest OSHA Area
Office listed in your telephone directory under United States
Government/Department of Labor.
Appendix C to Sec. 1910.1025--Medical Surveillance Guidelines
introduction
The primary purpose of the Occupational Safety and Health Act of
1970 is to assure, so far as possible, safe and healthful working
conditions for every working man and woman. The occupational health
standard for inorganic lead1 was promulgated to protect
workers exposed to inorganic lead including metallic lead, all inorganic
lead compounds and organic lead soaps.
---------------------------------------------------------------------------
1 The term inorganic lead used throughout the medical
surveillance appendices is meant to be synonymous with the definition of
lead set forth in the standard.
---------------------------------------------------------------------------
Under this final standard in effect as of March 1, 1979,
occupational exposure to inorganic lead is to be limited to 50
g/m3 (micrograms per cubic meter) based on an 8 hour
time-weighted average (TWA). This level of exposure eventually must be
achieved through a combination of engineering, work practice and other
administrative controls. Periods of time ranging from 1 to 10 years are
provided for different industries to implement these controls. The
schedule which is based on individual industry considerations is given
in Table 1. Until these controls are in place, respirators must be used
to meet the 50 g/m3 exposure limit.
The standard also provides for a program of biological monitoring
and medical surveillance for all employees exposed to levels of
inorganic lead above the action level of 30 g/m3
(TWA) for more than 30 days per year.
The purpose of this document is to outline the medical surveillance
provisions of the standard for inorganic lead, and to provide further
information to the physician regarding the examination and evaluation of
workers exposed to inorganic lead.
Section 1 provides a detailed description of the monitoring
procedure including the required frequency of blood testing for exposed
workers, provisions for medical removal protection (MRP), the
recommended right of the employee to a second medical opinion, and
notification and recordkeeping requirements of the employer. A
discussion of the requirements for respirator use and respirator
monitoring and OSHA's position on prophylactic chelation therapy are
also included in this section.
Section 2 discusses the toxic effects and clinical manifestations of
lead poisoning and effects of lead intoxication on enzymatic pathways in
heme synthesis. The adverse effects on both male and female reproductive
capacity and on the fetus are also discussed.
Section 3 outlines the recommended medical evaluation of the worker
exposed to inorganic lead including details of the medical history,
physical examination, and recommended laboratory tests, which are based
on the toxic effects of lead as discussed in Section 2.
Section 4 provides detailed information concerning the laboratory
tests available for the monitoring of exposed workers. Included also is
a discussion of the relative value of each test and the limitations and
precautions which are necessary in the interpretation of the laboratory
results.
Table 1
----------------------------------------------------------------------------------------------------------------
Effective date
-----------------------------------------------------------
Permissible airborne lead levels by industry (g/m3) \1\ Mar. 1, Mar. 1, Mar. 1, Mar. 1, Mar. 1, 1989
1979 1980 1981 1982 1984 (final)
----------------------------------------------------------------------------------------------------------------
1. Primary lead production.......................... 200 200 200 100 100 50
2. Secondary lead production........................ 200 200 200 100 50 50
3. Lead-acid battery manufacturing.................. 200 200 100 100 50 50
4. Nonferrous foundries............................. 200 100 100 100 50 50
[[Page 127]]
5. Lead pigment manufacturing....................... 200 200 200 100 50 50
6. All other industries............................. 200 50 50 50 50 50
----------------------------------------------------------------------------------------------------------------
\1\ Airborne levels to be achieved without reliance or respirator protection through a combination of
engineering, work practice and other administrative controls. While these controls are being implemented
respirators must be used to meet the 50 g/m3 exposure limit.
i. medical surveillance and monitoring requirements for workers exposed
to inorganic lead
Under the occupational health standard for inorganic lead, a program
of biological monitoring and medical surveillance is to be made
available to all employees exposed to lead above the action level of 30
g/m3 TWA for more than 30 days each year. This
program consists of periodic blood sampling and medical evaluation to be
performed on a schedule which is defined by previous laboratory results,
worker complaints or concerns, and the clinical assessment of the
examining physician.
Under this program, the blood lead level of all employees who are
exposed to lead above the action level of 30 g/m3 is
to be determined at least every six months. The frequency is increased
to every two months for employees whose last blood lead level was
between 40 g/100 g whole blood and the level requiring
employee medical removal to be discussed below. For employees who are
removed from exposure to lead due to an elevated blood lead, a new blood
lead level must be measured monthly. A zinc protoporphyrin (ZPP) is
required on each occasion that a blood lead level measurement is made.
An annual medical examination and consultation performed under the
guidelines discussed in Section 3 is to be made available to each
employee for whom a blood test conducted at any time during the
preceding 12 months indicated a blood lead level at or above 40
g/100 g. Also, an examination is to be given to all employees
prior to their assignment to an area in which airborne lead
concentrations reach or exceed the action level. In addition, a medical
examination must be provided as soon as possible after notification by
an employee that the employee has developed signs or symptoms commonly
associated with lead intoxication, that the employee desires medical
advice regarding lead exposure and the ability to procreate a healthy
child, or that the employee has demonstrated difficulty in breathing
during a respirator fitting test or during respirator use. An
examination is also to be made available to each employee removed from
exposure to lead due to a risk of sustaining material impairment to
health, or otherwise limited or specially protected pursuant to medical
recommendations.
Results of biological monitoring or the recommendations of an
examining physician may necessitate removal of an employee from further
lead exposure pursuant to the standard's medical removal protection
(MRP) program. The object of the MRP program is to provide temporary
medical removal to workers either with substantially elevated blood lead
levels or otherwise at risk of sustaining material health impairment
from continued substantial exposure to lead. The following guidelines
which are summarized in Table 2 were created under the standard for the
temporary removal of an exposed employee and his or her subsequent
return to work in an exposure area.
Table 2
----------------------------------------------------------------------------------------------------------------
Effective date
--------------------------------------------------------------------------------
Mar. 1, 1983
Mar. 1, 1979 Mar. 1, 1980 Mar. 1, 1981 Mar. 1, 1982 (final)
----------------------------------------------------------------------------------------------------------------
A. Blood lead level requiring 80 g/ 70g/ 60 g/ 60 g/ 60g/100
employee medical removal. 100 g 100 g 100 g 100 g g or average of
(Level must be confirmed with last three blood
second follow-up blood lead samples or all
level within two weeks of blood samples
first report.). over previous 6
months
(whichever is
over a longer
time period) is
50 g/
100 g or greater
unless last
blood sample is
40 g/
100 g or less.
[[Page 128]]
B. Frequency which employees
exposed to action level of
lead (30 g/m3 TWA)
must have blood lead level
checked (ZPP is also required
in each occasion that a blood
lead is obtained.):
1. Last blood lead level less Every 6 months Every 6 months Every 6 Every 6 Every 6 months.
than 40 g/100 g. months months
2. Last blood lead level Every 2 months Every 2 months Every 2 Every 2 Every 2 months.
between 40 g/100 g months months
and level requiring medical
removal (see A above).
3. Employees removed from Every 1 month Every 1 month Every 1 month Every 1 month Every 1 month.
exposure to lead because of
an elevated blood lead level.
C. Permissible airborne 100 g/ 50 g/ 30 g/ 30 g/ 30 g/m3
exposure limit for workers m3 8 hr TWA m3 8 hr TWA m3 8 hr TWA m3 8 hr TWA 8 hr TWA.
removed from work due to an
elevated blood lead level
(without regard to respirator
protection).
D. Blood lead level confirmed 60 50 40 40 40
with a second blood analysis, g/ g/ g/ g/ g/100
at which employee may return 100 g 100 g 100 g 100 g g.
to work. Permissible exposure
without regard to respirator
protection is listed by
industry in Table I.
----------------------------------------------------------------------------------------------------------------
Note: When medical opinion indicates that an employee is at risk of material impairment from exposure to lead,
the physician can remove an employee from exposures exceeding the action level (or less) or recommend special
protective measures as deemed appropriate and necessary. Medical monitoring during the medical removal period
can be more stringent than noted in the table above if the physician so specifies. Return to work or removal
of limitations and special protections is permitted when the physician indicates that the worker is no longer
at risk of material impairment.
Under the standard's ultimate worker removal criteria, a worker is
to be removed from any work having any eight hour TWA exposure to lead
of 30 g/m3 or more whenever either of the following
circumstances apply: (1) a blood lead level of 60 g/100 g or
greater is obtained and confirmed by a second follow-up blood lead level
performed within two weeks after the employer receives the results of
the first blood sampling test, or (2) the average of the previous three
blood lead determinations or the average of all blood lead
determinations conducted during the previous six months, whichever
encompasses the longest time period, equals or exceeds 50 g/
100 g, unless the last blood sample indicates a blood lead level at or
below 40 g/100 g in which case the employee need not be
removed. Medical removal is to continue until two consecutive blood lead
levels are 40 g/100 g or less.
During the first two years that the ultimate removal criteria are
being phased in, the return criteria have been set to assure that a
worker's blood lead level has substantially declined during the period
of removal. From March 1, 1979 to March 1, 1980, the blood lead level
requiring employee medical removal is 80 g/100 g. Workers
found to have a confirmed blood lead at this level or greater need only
be removed from work having a daily 8 hour TWA exposure to lead at or
above 100 g/m3. Workers so removed are to be
returned to work when their blood lead levels are at or below 60
g/100 g of whole blood. From March 1, 1980 to March 1, 1981,
the blood lead level requiring medical removal is 70 g/100 g.
During this period workers need only be removed from jobs having a daily
8 hour TWA exposure to lead at or above 50 g/m3 and
are to be returned to work when a level of 50 g/100 g is
achieved. Beginning March 1, 1981, return depends on a worker's blood
lead level declining to 40 g/100 g of whole blood.
As part of the standard, the employer is required to notify in
writing each employee whose blood lead level exceeds 40 g/100
g. In addition each such employee is to be informed that the standard
requires medical removal with MRP benefits, discussed below, when an
employee's blood lead level exceeds the above defined limits.
In addition to the above blood lead level criteria, temporary worker
removal may also take place as a result of medical determinations and
recommendations. Written medical opinions must be prepared after each
examination pursuant to the standard. If the examining physician
includes a medical finding, determination or opinion that the employee
has a medical condition which
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places the employee at increased risk of material health impairment from
exposure to lead, then the employee must be removed from exposure to
lead at or above the action level. Alternatively, if the examining
physician recommends special protective measures for an employee (e.g.,
use of a powered air purifying respirator) or recommends limitations on
an employee's exposure to lead, then the employer must implement these
recommendations. Recommendations may be more stringent than the specific
provisions of the standard. The examining physician, therefore, is given
broad flexibility to tailor special protective procedures to the needs
of individual employees. This flexibility extends to the evaluation and
management of pregnant workers and male and female workers who are
planning to raise children. Based on the history, physical examination,
and laboratory studies, the physician might recommend special protective
measures or medical removal for an employee who is pregnant or who is
planning to conceive a child when, in the physician's judgment,
continued exposure to lead at the current job would pose a significant
risk. The return of the employee to his or her former job status, or the
removal of special protections or limitations, depends upon the
examining physician determining that the employee is no longer at
increased risk of material impairment or that special measures are no
longer needed.
During the period of any form of special protection or removal, the
employer must maintain the worker's earnings, seniority, and other
employment rights and benefits (as though the worker had not been
removed) for a period of up to 18 months. This economic protection will
maximize meaningful worker participation in the medical surveillance
program, and is appropriate as part of the employer's overall obligation
to provide a safe and healthful workplace. The provisions of MRP
benefits during the employee's removal period may, however, be
conditioned upon participation in medical surveillance.
On rare occasions, an employee's blood lead level may not acceptably
decline within 18 months of removal. This situation will arise only in
unusual circumstances, thus the standard relies on an individual medical
examination to determine how to protect such an employee. This medical
determination is to be based on both laboratory values, including lead
levels, zinc protoporphyrin levels, blood counts, and other tests felt
to be warranted, as well as the physician's judgment that any symptoms
or findings on physical examination are a result of lead toxicity. The
medical determination may be that the employee is incapable of ever
safely returning to his or her former job status. The medical
determination may provide additional removal time past 18 months for
some employees or specify special protective measures to be implemented.
The lead standard provides for a multiple physician review in cases
where the employee wishes a second opinion concerning potential lead
poisoning or toxicity. If an employee wishes a second opinion, he or she
can make an appointment with a physician of his or her choice. This
second physician will review the findings, recommendations or
determinations of the first physician and conduct any examinations,
consultations or tests deemed necessary in an attempt to make a final
medical determination. If the first and second physicians do not agree
in their assessment they must try to resolve their differences. If they
cannot reach an agreement then they must designate a third physician to
resolve the dispute.
The employer must provide examining and consulting physicians with
the following specific information: a copy of the lead regulations and
all appendices, a description of the employee's duties as related to
exposure, the exposure level to lead and any other toxic substances (if
applicable), a description of personal protective equipment used, blood
lead levels, and all prior written medical opinions regarding the
employee in the employer's possession or control. The employer must also
obtain from the physician and provide the employee with a written
medical opinion containing blood lead levels, the physicians's opinion
as to whether the employee is at risk of material impairment to health,
any recommended protective measures for the employee if further exposure
is permitted, as well as any recommended limitations upon an employee's
use of respirators.
Employers must instruct each physician not to reveal to the employer
in writing or in any other way his or her findings, laboratory results,
or diagnoses which are felt to be unrelated to occupational lead
exposure. They must also instruct each physician to advise the employee
of any occupationally or non-occupationally related medical condition
requiring further treatment or evaluation.
The standard provides for the use of respirators where engineering
and other primary controls have not been fully implemented. However, the
use of respirator protection shall not be used in lieu of temporary
medical removal due to elevated blood lead levels or findings that an
employee is at risk of material health impairment. This is based on the
numerous inadequacies of respirators including skin rash where the
facepiece makes contact with the skin, unacceptable stress to breathing
in some workers with underlying cardiopulmonary impairment, difficulty
in providing adequate fit, the tendency for respirators to create
additional hazards by interfering with vision, hearing, and mobility,
and the difficulties of assuring the maximum effectiveness of a
complicated work practice program involving respirators.
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Respirators do, however, serve a useful function where engineering and
work practice controls are inadequate by providing supplementary,
interim, or short-term protection, provided they are properly selected
for the environment in which the employee will be working, properly
fitted to the employee, maintained and cleaned periodically, and worn by
the employee when required.
In its final standard on occupational exposure to inorganic lead,
OSHA has prohibited prophylactic chelation. Diagnostic and therapeutic
chelation are permitted only under the supervision of a licensed
physician with appropriate medical monitoring in an acceptable clinical
setting. The decision to initiate chelation therapy must be made on an
individual basis and take into account the severity of symptoms felt to
be a result of lead toxicity along with blood lead levels, ZPP levels,
and other laboratory tests as appropriate. EDTA and penicillamine which
are the primary chelating agents used in the therapy of occupational
lead poisoning have significant potential side effects and their use
must be justified on the basis of expected benefits to the worker.
Unless frank and severe symptoms are present, therapeutic chelation is
not recommended given the opportunity to remove a worker from exposure
and allow the body to naturally excrete accumulated lead. As a
diagnostic aid, the chelation mobilization test using CA-EDTA has
limited applicability. According to some investigators, the test can
differentiate between lead-induced and other nephropathies. The test may
also provide an estimation of the mobile fraction of the total body lead
burden.
Employers are required to assure that accurate records are
maintained on exposure monitoring, medical surveillance, and medical
removal for each employee. Exposure monitoring and medical surveillance
records must be kept for 40 years or the duration of employment plus 20
years, whichever is longer, while medical removal records must be
maintained for the duration of employment. All records required under
the standard must be made available upon request to the Assistant
Secretary of Labor for Occupational Safety and Health and the Director
of the National Institute for Occupational Safety and Health. Employers
must also make environmental and biological monitoring and medical
removal records available to affected employees and to former employees
or their authorized employee representatives. Employees or their
specifically designated representatives have access to their entire
medical surveillance records.
In addition, the standard requires that the employer inform all
workers exposed to lead at or above the action level of the provisions
of the standard and all its appendices, the purpose and description of
medical surveillance and provisions for medical removal protection if
temporary removal is required. An understanding of the potential health
effects of lead exposure by all exposed employees along with full
understanding of their rights under the lead standard is essential for
an effective monitoring program.
ii. adverse health effects of inorganic lead
Although the toxicity of lead has been known for 2,000 years, the
knowledge of the complex relationship between lead exposure and human
response is still being refined. Significant research into the toxic
properties of lead continues throughout the world, and it should be
anticipated that our understanding of thresholds of effects and margins
of safety will be improved in future years. The provisions of the lead
standard are founded on two prime medical judgments: first, the
prevention of adverse health effects from exposure to lead throughout a
working lifetime requires that worker blood lead levels be maintained at
or below 40 g/100 g and second, the blood lead levels of
workers, male or female, who intend to parent in the near future should
be maintained below 30 g/100 g to minimize adverse
reproductive health effects to the parents and developing fetus. The
adverse effects of lead on reproduction are being actively researched
and OSHA encourages the physician to remain abreast of recent
developments in the area to best advise pregnant workers or workers
planning to conceive children.
The spectrum of health effects caused by lead exposure can be
subdivided into five developmental stages: normal, physiological changes
of uncertain significance, pathophysiological changes, overt symptoms
(morbidity), and mortality. Within this process there are no sharp
distinctions, but rather a continuum of effects. Boundaries between
categories overlap due to the wide variation of individual responses and
exposures in the working population. OSHA's development of the lead
standard focused on pathophysiological changes as well as later stages
of disease.
1. Heme Synthesis Inhibition. The earliest demonstrated effect of
lead involves its ability to inhibit at least two enzymes of the heme
synthesis pathway at very low blood levels. Inhibition of delta
aminolevulinic acid dehydrase (ALA-D) which catalyzes the conversion of
delta-aminolevulinic acid (ALA) to protoporphyrin is observed at a blood
lead level below 20 g/100 g whole blood. At a blood lead level
of 40 ug/100 g, more than 20% of the population would have 70%
inhibition of ALA-D. There is an exponential increase in ALA excretion
at blood lead levels greater than 40 g/100 g.
Another enzyme, ferrochelatase, is also inhibited at low blood lead
levels. Inhibition of ferrochelatase leads to increased free erythrocyte
protoporphyrin (FEP) in the blood
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which can then bind to zinc to yield zinc protoporphyrin. At a blood
lead level of 50 g/100 g or greater, nearly 100% of the
population will have an increase in FEP. There is also an exponential
relationship between blood lead levels greater than 40 g/100 g
and the associated ZPP level, which has led to the development of the
ZPP screening test for lead exposure.
While the significance of these effects is subject to debate, it is
OSHA's position that these enzyme disturbances are early stages of a
disease process which may eventually result in the clinical symptoms of
lead poisoning. Whether or not the effects do progress to the later
stages of clinical disease, disruption of these enzyme processes over a
working lifetime is considered to be a material impairment of health.
One of the eventual results of lead-induced inhibition of enzymes in
the heme synthesis pathway is anemia which can be asymptomatic if mild
but associated with a wide array of symptoms including dizziness,
fatigue, and tachycardia when more severe. Studies have indicated that
lead levels as low as 50 g/100 g can be associated with a
definite decreased hemoglobin, although most cases of lead-induced
anemia, as well as shortened red-cell survival times, occur at lead
levels exceeding 80 g/100 g. Inhibited hemoglobin synthesis is
more common in chronic cases whereas shortened erythrocyte life span is
more common in acute cases.
In lead-induced anemias, there is usually a reticulocytosis along
with the presence of basophilic stippling, and ringed sideroblasts,
although none of the above are pathognomonic for lead-induced anemia.
2. Neurological Effects. Inorganic lead has been found to have toxic
effects on both the central and peripheral nervous systems. The earliest
stages of lead-induced central nervous system effects first manifest
themselves in the form of behavioral disturbances and central nervous
system symptoms including irritability, restlessness, insomnia and other
sleep disturbances, fatigue, vertigo, headache, poor memory, tremor,
depression, and apathy. With more severe exposure, symptoms can progress
to drowsiness, stupor, hallucinations, delerium, convulsions and coma.
The most severe and acute form of lead poisoning which usually
follows ingestion or inhalation of large amounts of lead is acute
encephalopathy which may arise precipitously with the onset of
intractable seizures, coma, cardiorespiratory arrest, and death within
48 hours.
While there is disagreement about what exposure levels are needed to
produce the earliest symptoms, most experts agree that symptoms
definitely can occur at blood lead levels of 60 g/100 g whole
blood and therefore recommend a 40 g/100 g maximum. The
central nervous system effects frequently are not reversible following
discontinued exposure or chelation therapy and when improvement does
occur, it is almost always only partial.
The peripheral neuropathy resulting from lead exposure
characteristically involves only motor function with minimal sensory
damage and has a marked predilection for the extensor muscles of the
most active extremity. The peripheral neuropathy can occur with varying
degrees of severity. The earliest and mildest form which can be detected
in workers with blood lead levels as low as 50 g/100 g is
manifested by slowing of motor nerve conduction velocity often without
clinical symptoms. With progression of the neuropathy there is
development of painless extensor muscle weakness usually involving the
extensor muscles of the fingers and hand in the most active upper
extremity, followed in severe cases by wrist drop or, much less
commonly, foot drop.
In addition to slowing of nerve conduction, electromyographical
studies in patients with blood lead levels greater than 50 g/
100 g have demonstrated a decrease in the number of acting motor unit
potentials, an increase in the duration of motor unit potentials, and
spontaneous pathological activity including fibrillations and
fasciculations. Whether these effects occur at levels of 40 g/
100 g is undetermined.
While the peripheral neuropathies can occasionally be reversed with
therapy, again such recovery is not assured particularly in the more
severe neuropathies and often improvement is only partial. The lack of
reversibility is felt to be due in part to segmental demyelination.
3. Gastrointestinal. Lead may also affect the gastrointestinal
system producing abdominal colic or diffuse abdominal pain,
constipation, obstipation, diarrhea, anorexia, nausea and vomiting. Lead
colic rarely develops at blood lead levels below 80 g/100 g.
4. Renal. Renal toxicity represents one of the most serious health
effects of lead poisoning. In the early stages of disease nuclear
inclusion bodies can frequently be identified in proximal renal tubular
cells. Renal function remains normal and the changes in this stage are
probably reversible. With more advanced disease there is progressive
interstitial fibrosis and impaired renal function. Eventually extensive
interstitial fibrosis ensues with sclerotic glomeruli and dilated and
atrophied proximal tubules; all represent end stage kidney disease.
Azotemia can be progressive, eventually resulting in frank uremia
necessitating dialysis. There is occasionally associated hypertension
and hyperuricemia with or without gout.
Early kidney disease is difficult to detect. The urinalysis is
normal in early lead nephropathy and the blood urea nitrogen and serum
creatinine increase only when two-
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thirds of kidney function is lost. Measurement of creatinine clearance
can often detect earlier disease as can other methods of measurement of
glomerular filtration rate. An abnormal Ca-EDTA mobilization test has
been used to differentiate between lead-induced and other nephropathies,
but this procedure is not widely accepted. A form of Fanconi syndrome
with aminoaciduria, glycosuria, and hyperphosphaturia indicating severe
injury to the proximal renal tubules is occasionally seen in children.
5. Reproductive effects. Exposure to lead can have serious effects
on reproductive function in both males and females. In male workers
exposed to lead there can be a decrease in sexual drive, impotence,
decreased ability to produce healthy sperm, and sterility. Malformed
sperm (teratospermia), decreased number of sperm (hypospermia), and
sperm with decreased motility (asthenospermia) can all occur.
Teratospermia has been noted at mean blood lead levels of 53
g/100 g and hypospermia and asthenospermia at 41 g/100 g.
Furthermore, there appears to be a dose-response relationship for
teratospermia in lead exposed workers.
Women exposed to lead may experience menstrual disturbances
including dysmenorrhea, menorrhagia and amenorrhea. Following exposure
to lead, women have a higher frequency of sterility, premature births,
spontaneous miscarriages, and stillbirths.
Germ cells can be affected by lead and cause genetic damage in the
egg or sperm cells before conception and result in failure to implant,
miscarriage, stillbirth, or birth defects.
Infants of mothers with lead poisoning have a higher mortality
during the first year and suffer from lowered birth weights, slower
growth, and nervous system disorders.
Lead can pass through the placental barrier and lead levels in the
mother's blood are comparable to concentrations of lead in the umbilical
cord at birth. Transplacental passage becomes detectable at 12-14 weeks
of gestation and increases until birth.
There is little direct data on damage to the fetus from exposure to
lead but it is generally assumed that the fetus and newborn would be at
least as susceptible to neurological damage as young children. Blood
lead levels of 50-60 g/100 g in children can cause significant
neurobehavioral impairments and there is evidence of hyperactivity at
blood levels as low as 25 g/100 g. Given the overall body of
literature concerning the adverse health effects of lead in children,
OSHA feels that the blood lead level in children should be maintained
below 30 g/100 g with a population mean of 15 g/100
g. Blood lead levels in the fetus and newborn likewise should not exceed
30 g/100 g.
Because of lead's ability to pass through the placental barrier and
also because of the demonstrated adverse effects of lead on reproductive
function in both the male and female as well as the risk of genetic
damage of lead on both the ovum and sperm, OSHA recommends a 30
g/100 g maximum permissible blood lead level in both males and
females who wish to bear children.
6. Other toxic effects. Debate and research continue on the effects
of lead on the human body. Hypertension has frequently been noted in
occupationally exposed individuals although it is difficult to assess
whether this is due to lead's adverse effects on the kidney or if some
other mechanism is involved. Vascular and electrocardiogarphic changes
have been detected but have not been well characterized. Lead is thought
to impair thyroid function and interfere with the pituitary-adrenal
axis, but again these effects have not been well defined.
iii. medical evaluation
The most important principle in evaluating a worker for any
occupational disease including lead poisoning is a high index of
suspicion on the part of the examining physician. As discussed in
Section 2, lead can affect numerous organ systems and produce a wide
array of signs and symptoms, most of which are non-specific and subtle
in nature at least in the early stages of disease. Unless serious
concern for lead toxicity is present, many of the early clues to
diagnosis may easily be overlooked.
The crucial initial step in the medical evaluation is recognizing
that a worker's employment can result in exposure to lead. The worker
will frequently be able to define exposures to lead and lead containing
materials but often will not volunteer this information unless
specifically asked. In other situations the worker may not know of any
exposures to lead but the suspicion might be raised on the part of the
physician because of the industry or occupation of the worker. Potential
occupational exposure to lead and its compounds occur in at least 120
occupations, including lead smelting, the manufacture of lead storage
batteries, the manufacture of lead pigments and products containing
pigments, solder manufacture, shipbuilding and ship repair, auto
manufacturing, construction, and painting.
Once the possibility for lead exposure is raised, the focus can then
be directed toward eliciting information from the medical history,
physical exam, and finally from laboratory data to evaluate the worker
for potential lead toxicity.
A complete and detailed work history is important in the initial
evaluation. A listing of all previous employment with information on
work processes, exposure to fumes or dust, known exposures to lead or
other toxic substances, respiratory protection used, and previous
medical surveillance should all be
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included in the worker's record. Where exposure to lead is suspected,
information concerning on-the-job personal hygiene, smoking or eating
habits in work areas, laundry procedures, and use of any protective
clothing or respiratory protection equipment should be noted. A complete
work history is essential in the medical evaluation of a worker with
suspected lead toxicity, especially when long term effects such as
neurotoxicity and nephrotoxicity are considered.
The medical history is also of fundamental importance and should
include a listing of all past and current medical conditions, current
medications including proprietary drug intake, previous surgeries and
hospitalizations, allergies, smoking history, alcohol consumption, and
also non-occupational lead exposures such as hobbies (hunting, riflery).
Also known childhood exposures should be elicited. Any previous history
of hematological, neurological, gastrointestinal, renal, psychological,
gynecological, genetic, or reproductive problems should be specifically
noted.
A careful and complete review must be performed to assess both
recognized complaints and subtle or slowly acquired symptoms which the
worker might not appreciate as being significant. The review of symptoms
should include the following:
General--weight loss, fatigue, decreased appetite.
Head, Eyes, Ears, Nose, Throat (HEENT)--headaches, visual
disturbances or decreased visual acuity, hearing deficits or tinnitus,
pigmentation of the oral mucosa, or metallic taste in mouth.
Cardio-pulmonary--shortness of breath, cough, chest pains,
palpitations, or orthopnea.
Gastrointestinal--nausea, vomiting, heartburn, abdominal pain,
constipation or diarrhea.
Neurologic--irritability, insomnia, weakness (fatigue), dizziness,
loss of memory, confusion, hallucinations, incoordination, ataxia,
decreased strength in hands or feet, disturbances in gait, difficulty in
climbing stairs, or seizures.
Hematologic--pallor, easy fatigability, abnormal blood loss, melena.
Reproductive (male and female and spouse where relevant)--history of
infertility, impotence, loss of libido, abnormal menstrual periods,
history of miscarriages, stillbirths, or children with birth defects.
Musculo-skeletal--muscle and joint pains.
The physical examination should emphasize the neurological,
gastrointestinal, and cardiovascular systems. The worker's weight and
blood pressure should be recorded and the oral mucosa checked for
pigmentation characteristic of a possible Burtonian or lead line on the
gingiva. It should be noted, however, that the lead line may not be
present even in severe lead poisoning if good oral hygiene is practiced.
The presence of pallor on skin examination may indicate an anemia,
which if severe might also be associated with a tachycardia. If an
anemia is suspected, an active search for blood loss should be
undertaken including potential blood loss through the gastrointestinal
tract.
A complete neurological examination should include an adequate
mental status evaluation including a search for behavioral and
psychological disturbances, memory testing, evaluation for irritability,
insomnia, hallucinations, and mental clouding. Gait and coordination
should be examined along with close observation for tremor. A detailed
evaluation of peripheral nerve function including careful sensory and
motor function testing is warranted. Strength testing particularly of
extensor muscle groups of all extremities is of fundamental importance.
Cranial nerve evaluation should also be included in the routine
examination.
The abdominal examination should include auscultation for bowel
sounds and abdominal bruits and palpation for organomegaly, masses, and
diffuse abdominal tenderness.
Cardiovascular examination should evaluate possible early signs of
congestive heart failure. Pulmonary status should be addressed
particularly if respirator protection is contemplated.
As part of the medical evaluation, the lead standard requires the
following laboratory studies:
1. Blood lead level
2. Hemoglobin and hematocrit determinations, red cell indices, and
examination of the peripheral blood smear to evaluate red blood cell
morphology
3. Blood urea nitrogen
4. Serum creatinine
5. Routine urinalysis with microscopic examination.
6. A zinc protoporphyrin level
In addition to the above, the physician is authorized to order any
further laboratory or other tests which he or she deems necessary in
accordance with sound medical practice. The evaluation must also include
pregnancy testing or laboratory evaluation of male fertility if
requested by the employee.
Additional tests which are probably not warranted on a routine basis
but may be appropriate when blood lead and ZPP levels are equivocal
include delta aminolevulinic acid and coproporphyrin concentrations in
the urine, and dark-field illumination for detection of basophilic
stippling in red blood cells.
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If an anemia is detected further studies including a careful
examination of the peripheral smear, reticulocyte count, stool for
occult blood, serum iron, total iron binding capacity, bilirubin, and,
if appropriate, vitamin B12 and folate may be of value in attempting to
identify the cause of the anemia.
If a peripheral neuropathy is suspected, nerve conduction studies
are warranted both for diagnosis and as a basis to monitor any therapy.
If renal disease is questioned, a 24 hour urine collection for
creatinine clearance, protein, and electrolytes may be indicated.
Elevated uric acid levels may result from lead-induced renal disease and
a serum uric acid level might be performed.
An electrocardiogram and chest x-ray may be obtained as deemed
appropriate.
Sophisticated and highly specialized testing should not be done
routinely and where indicated should be under the direction of a
specialist.
iv. laboratory evaluation
The blood lead level at present remains the single most important
test to monitor lead exposure and is the test used in the medical
surveillance program under the lead standard to guide employee medical
removal. The ZPP has several advantages over the blood lead level.
Because of its relatively recent development and the lack of extensive
data concerning its interpretation, the ZPP currently remains an
ancillary test.
This section will discuss the blood lead level and ZPP in detail and
will outline their relative advantages and disadvantages. Other blood
tests currently available to evaluate lead exposure will also be
reviewed.
The blood lead level is a good index of current or recent lead
absorption when there is no anemia present and when the worker has not
taken any chelating agents. However, blood lead levels along with
urinary lead levels do not necessarily indicate the total body burden of
lead and are not adequate measures of past exposure. One reason for this
is that lead has a high affinity for bone and up to 90% of the body's
total lead is deposited there. A very important component of the total
lead body burden is lead in soft tissue (liver, kidney, and brain). This
fraction of the lead body burden, the biologically active lead, is not
entirely reflected by blood lead levels since it is a function of the
dynamics of lead absorption, distribution, deposition in bone and
excretion. Following discontinuation of exposure to lead, the excess
body burden is only slowly mobilized from bone and other relatively
stable body stores and excreted. Consequently, a high blood lead level
may only represent recent heavy exposure to lead without a significant
total body excess and likewise a low blood lead level does not exclude
an elevated total body burden of lead.
Also due to its correlation with recent exposures, the blood lead
level may vary considerably over short time intervals.
To minimize laboratory error and erroneous results due to
contamination, blood specimens must be carefully collected after
thorough cleaning of the skin with appropriate methods using lead-free
blood containers and analyzed by a reliable laboratory. Under the
standard, samples must be analyzed in laboratories which are approved by
the Center for Disease Control (CDC) or which have received satisfactory
grades in proficiency testing by the CDC in the previous year. Analysis
is to be made using atomic absorption spectrophotometry, anodic
stripping voltammetry or any method which meets the accuracy
requirements set forth by the standard.
The determination of lead in urine is generally considered a less
reliable monitoring technique than analysis of whole blood primarily due
to individual variability in urinary excretion capacity as well as the
technical difficulty of obtaining accurate 24 hour urine collections. In
addition, workers with renal insufficiency, whether due to lead or some
other cause, may have decreased lead clearance and consequently urine
lead levels may underestimate the true lead burden. Therefore, urine
lead levels should not be used as a routine test.
The zinc protoporphyrin test, unlike the blood lead determination,
measures an adverse metabolic effect of lead and as such is a better
indicator of lead toxicity than the level of blood lead itself. The
level of ZPP reflects lead absorption over the preceding 3 to 4 months,
and therefore is a better indicator of lead body burden. The ZPP
requires more time than the blood lead to read significantly elevated
levels; the return to normal after discontinuing lead exposure is also
slower. Furthermore, the ZPP test is simpler, faster, and less expensive
to perform and no contamination is possible. Many investigators believe
it is the most reliable means of monitoring chronic lead absorption.
Zinc protoporphyrin results from the inhibition of the enzyme
ferrochelatase which catalyzes the insertion of an iron molecule into
the protoporphyrin molecule, which then becomes heme. If iron is not
inserted into the molecule then zinc, having a greater affinity for
protoporphyrin, takes the place of the iron, forming ZPP.
An elevation in the level of circulating ZPP may occur at blood lead
levels as low as 20-30 g/100 g in some workers. Once the blood
lead level has reached 40 g/100 g there is more marked rise in
the ZPP value from its normal range of less than 100 g/100 ml.
Increases in blood lead levels beyond 40 g/
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100 g are associated with exponential increases in ZPP.
Whereas blood lead levels fluctuate over short time spans, ZPP
levels remain relatively stable. ZPP is measured directly in red blood
cells and is present for the cell's entire 120 day life-span. Therefore,
the ZPP level in blood reflects the average ZPP production over the
previous 3-4 months and consequently the average lead exposure during
that time interval.
It is recommended that a hematocrit be determined whenever a
confirmed ZPP of 50 g/100 ml whole blood is obtained to rule
out a significant underlying anemia. If the ZPP is in excess of 100