[Federal Register Volume 64, Number 88 (Friday, May 7, 1999)]
[Notices]
[Pages 24709-24711]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-11545]



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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration
[Docket No. NHTSA-99-5101; Notice 1]


Comments on Truck Splash and Spray Reduction for a Report to 
Congress

AGENCY: National Highway Traffic Safety Administration (NHTSA), DOT.

ACTION: Notice requesting comments.

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SUMMARY: The Senate Appropriations Committee has directed NHTSA to 
provide Congress with a report updating the agency's research on truck 
splash and spray by conducting a comprehensive review and evaluation of 
spray suppression measures that can be employed on heavy duty vehicles 
to provide clearer highway visibility and safety during periods of 
adverse weather conditions. The report is due to Congress by October 
21, 1999. This notice invites any interested person to provide NHTSA 
with any information or data in this area that the person believes 
NHTSA should consider in preparing this report to Congress.

DATES: All comments received by NHTSA no later than June 21, 1999 will 
be considered in preparing this report to Congress on progress in heavy 
vehicle splash and spray suppression.

ADDRESSES: All comments should refer to Docket No. NHTSA-99-5101; 
Notice 7 and be submitted to: Docket Management, Room PL-401, 400 
Seventh Street, SW, Washington, D.C. 20590. Docket hours are from 10:00 
a.m. to 5:00 p.m. Monday through Friday.
    For public comments and other information related to previous 
notices on this subject, please refer to Docket No. 83-005, NHTSA 
Docket, Room 5111, 400 Seventh Street, SW, Washington, DC 20590. NHTSA 
Docket hours are from 9:30 am to 4:00 pm Monday through Friday.

FOR FURTHER INFORMATION CONTACT: Mr. Jere Medlin, Office of Crash 
Avoidance Standards, NPS-20, National Highway Traffic Safety 
Administration, 400 Seventh Street, SW, Washington, DC 20590, telephone 
(202) 366-5276, fax (202) 366-4329.

SUPPLEMENTARY INFORMATION: The terms ``splash and spray'' are commonly 
used to describe the adverse effects on driver visibility caused by 
other vehicles when traveling on wet roads. While spray clouds are 
produced by all vehicles traveling on wet roads, those produced by 
large trucks and buses are much larger than the clouds produced by 
passenger cars and light trucks. This can result in reduced driver 
visibility for adjacent motorists and for the driver of the large truck 
or bus.
    NHTSA and others have studied the subject of splash and spray for 
more than 30 years. The most recent time the agency evaluated this 
subject was in late 1993, in response to a request from the Senate 
Appropriations Committee. In its report on NHTSA's FY94 appropriation, 
the Committee asked that the agency report ``* * * on the status of 
recent technological progress in the design and testing of splash and 
spray suppression devices [for large commercial vehicles] and NHTSA's 
view on the need for regulation in this safety area.'' In response, 
NHTSA submitted a report to Congress in March 1994, ``Splash and Spray 
Suppression, Technological Developments in the Design and Testing of 
Spray Reduction Devices for Heavy Trucks'' (DOT HS 808 085), copies of 
which are available from the National Technical Information Service, 
Springfield, Virginia 22161. The report provided a comprehensive 
evaluation and summary of available data and studies conducted before 
and after NHTSA terminated rulemaking on splash and spray in 1988. The 
1994 report concluded the following about developments in splash and 
spray reduction for heavy trucks:

    1. There are no data available to support the position that 
heavy truck splash and spray presents a major safety problem, in 
terms of crashes caused and injuries in those crashes. The greatest 
involvement ever found for splash and spray was that it was a factor 
in 0.41% of crashes studied according to a 1959 British study. A 
more recent study in Indiana found that splash and spray could not 
be documented as a cause of any crash studied, and a North Carolina 
study found that splash and spray was a factor in 0.0055% of 450,000 
crashes evaluated. No information has become available since 1988 
suggesting that splash and spray is a larger safety problem than was 
previously known.
    2. No study or other information has become available since 1988 
that would cause the Agency to change its previous determination 
that no technology or combination of technologies has been 
demonstrated that will consistently and significantly reduce splash 
and spray from tractors, semi-trailers, and trailers to the extent 
that driver visibility will be significantly improved.
    3. Several manufacturers of large trucks believe that 
aerodynamic improvements, which were made to their vehicles in an 
effort to improve fuel economy and reduce operating costs, will also 
serve to reduce splash and spray. This belief is based on very 
limited testing under controlled conditions. More extensive testing 
conducted in connection with NHTSA's previous rulemaking indicated 
that aerodynamic devices are not as effective at suppressing spray 
in the presence of crosswinds. Previous engineering analysis 
suggested that aerodynamic devices on truck tractors would not be 
effective at reducing spray when the tractor was connected to a 
trailer or semitrailer that was not a van. The testing done to date 
by truck manufacturers of more aerodynamic tractors has not examined 
these previously identified concerns to see if they are still valid.
    4. The truck manufacturers appear to be working to reduce the 
splash and spray generated by their vehicles in the absence of any 
government requirement for them to do so. In addition to the efforts 
of Freightliner and Paccar in testing more aerodynamic truck 
tractors, the SAE has worked for years to develop a consensus test 
procedure that can be used to evaluate the performance of spray 
suppression devices.
    Given these circumstances and the information available to it, 
the Agency has no plans to initiate a new rulemaking action on heavy 
truck splash and spray reduction.

    More recently, in its report on NHTSA's appropriation for fiscal 
year 1999, the Senate Committee on Appropriations has again asked the 
agency to review this matter as follows:

    Spray suppression research.--The Committee acknowledges the work 
previously undertaken by NHTSA in the area of spray suppression 
research and evaluation of abatement technologies and continues to 
support further research by NHTSA in this area to make travel on the 
Nation's highways safer and less stressful. The Committee is aware 
of the progress made in the European Union in designing beneficial 
performance standards and implementing roadway spray suppression 
regulations to improve highway visibility. The Committee directs 
NHTSA to update its research by conducting a comprehensive review 
and evaluation of spray suppression measures that can be employed on 
heavy duty vehicles (over 8,500 pounds gross vehicle weight rating) 
to provide clearer highway visibility and safety during periods of 
adverse weather conditions. NHTSA shall publish and report its 
findings to Congress within 12 months of enactment.

    The agency has begun gathering the information it will need to 
respond to this request. NHTSA will conduct a comprehensive review and 
evaluation of spray suppression measures that can be employed on heavy 
duty vehicles to update its research since 1993. However, to ensure 
that the agency is aware of and considers all relevant information on 
this subject when preparing the Report to Congress, NHTSA is publishing 
this notice to invite public comment. All interested persons are 
invited to provide data and other relevant information which has become 
available since 1993, particularly developments that were not included 
in NHTSA's 1994 Report to Congress, concerning spray suppression 
measures that can be employed on heavy duty vehicles.

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    The agency will consider all public comments it has received by 
June 21, 1999, when preparing the report to Congress. While NHTSA is 
interested in any splash and spray information the public may have to 
offer, the agency is especially interested in responses to the 
following questions.

Questions

    1. Please provide information and data on any technological 
improvements made since 1993 in the design and/or testing of splash and 
spray devices for use on heavy duty vehicles. NHTSA is especially 
interested in supporting data that are the basis for the commenter's 
conclusion that the device represents a technological improvement that 
will consistently and significantly reduce splash and spray to the 
extent that driver visibility will be significantly improved.
    2. Please provide information on any data bases that NHTSA should 
examine or consider to estimate the extent to which splash and spray 
from heavy duty vehicles contributes to crashes on the public roads.
    3. In the agency's rulemaking on this subject that was terminated 
in 1988, NHTSA indicated that aerodynamic improvements, made by large 
truck manufacturers to their vehicles to improve fuel economy and 
reduce operating costs, had shown promise for reducing splash and spray 
in some situations. That is, if such aerodynamic devices were attached 
to a truck tractor pulling a van-type semitrailer and if there were 
little or no crosswind present, the devices could improve visibility to 
a level that would be helpful to other motorists. In its March 1994 
report to Congress, the agency indicated that several large truck 
manufacturers believed that aerodynamic improvements made since 1988 
would reduce splash and spray. However, this was based on very limited 
testing under controlled conditions. The testing done by truck 
manufacturers did not examine whether the previously identified 
concerns were still valid.
    Please provide information on any aerodynamic improvements to truck 
tractors since 1993, and data showing to what extent, if any, such 
improvements have lessened the amount of splash and spray generated by 
tractor/van-semitrailer combinations with crosswinds present. NHTSA had 
found in its testing that a crosswind of 8 miles per hour or more 
significantly diminished the benefits of the splash and spray 
countermeasures that were tested. In a 1987 rulemaking notice on this 
subject, NHTSA cited National Weather Service data indicating the mean 
wind velocity for the vast majority of the United States is 8 mph or 
greater. Similarly, please provide information and supporting data on 
other solutions that have been developed since 1993, which lessen the 
amount of splash and spray generated by other tractor/trailer 
combinations, such as tanks or flatbeds, or other types of heavy duty 
vehicles with crosswinds present.
    4. Please provide information on any aftermarket devices introduced 
since 1993 that are intended to reduce the amount of splash and spray 
generated by heavy duty vehicles. Include a specific description of the 
devices, a brief explanation of how they reduce splash and spray, and 
all tests and other data that demonstrate the devices are effective in 
reducing splash and spray across a range of heavy vehicles under 
representative weather conditions.
    5. If a person believes that some means would be effective at 
reducing splash and spray from tractor-single trailer combinations, 
please provide any information and data on whether that means would 
also work to reduce spray from tractors combined with double or triple 
trailers.
    6. In its March 1994 report to Congress, NHTSA provided a 
comprehensive summary of the data and studies that were conducted 
before and after the agency terminated its rulemaking on splash and 
spray in 1988. This included all relevant information of which the 
agency was aware. NHTSA would like commenters to provide information on 
any study or testing of splash and spray suppression measures that was 
not considered in the 1994 report to Congress but should be considered 
in preparing this report to Congress.
    7. Please provide information on the costs associated with splash 
and spray devices introduced since 1993, both original equipment and 
aftermarket, along with data on how effective the devices are at 
reducing splash and spray across a range of heavy duty vehicles and 
representative weather conditions.
    8. In its current request that NHTSA again review this matter, the 
Senate Appropriations Committee stated that ``The Committee is aware of 
the progress made in the European Union in designing beneficial 
performance standards and implementing roadway spray suppression 
regulations to improve highway visibility.'' NHTSA is aware of European 
Economic Community (EEC) Directive 91-226, ``Spray Suppression 
Systems,'' issued in April 1991. The Directive applies to heavy duty 
vehicles and involves EEC member component type-approval addressing two 
types of spray suppression devices: (1) energy absorption and (2) air/
water separator. The Directive includes laboratory performance tests of 
the devices along with vehicle location and component marking 
requirements.
    Please provide any information along with supporting data on how 
effective EEC Directive 91-226 has been at reducing splash and spray 
across a range of heavy duty vehicles and representative weather 
conditions, to what extent driver visibility is improved, and whether 
U.S. trucks would need additional equipment, like fenders, to achieve 
the same visibility benefits from the spray suppression equipment.
    9. In 1994 the Society of Automotive Engineers published a 
``Recommended Practice For Splash and Spray Evaluation,'' J2245. It 
provides general guidelines for measuring splash and spray from 
vehicles operating over wet pavements. The guidelines describe two 
methods of analysis: (1) video-digitizing and (2) laser. The video-
digitizing method uses video images and contrast measurements between 
black and white checkerboards when a spray cloud is superimposed on 
them as a means of measuring the obscuring spray. The laser method uses 
laser transmittance through the spray cloud as the means of 
measurement. The test procedures involve actual test vehicles fitted 
with splash and spray devices, and include measurements under various 
wind conditions.
    NHTSA is interested in any information along with supporting data 
on the use of these two test procedures by manufacturers and others. 
Specifically, the agency would like to know whether one method is 
preferred over the other, and why, along with information on the extent 
to which each method represents real world conditions. In addition, 
please provide any information on how well reductions in splash and 
spray through either method correlate to improvements in actual driver 
visibility.
    The agency invites written comments from all interested persons. It 
is requested that two copies of each written comment be submitted. As 
always, NHTSA will try to consider comments that it receives after the 
comment closing date. However, in this case, the deadline imposed by 
the Senate Appropriations Committee means that comments submitted after 
the closing date of June 21, 1999 are less likely to be considered.
    All comments must not exceed 15 pages in length (49 CFR 553.21). 
Necessary attachments may be appended to these submissions without

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regard to the 15 page limit. This limitation is intended to encourage 
commenters to detail their primary arguments in concise fashion.
    If a commenter wishes to submit specified information under a claim 
of confidentiality, three copies of the complete submission, including 
purportedly confidential business information, should be submitted to 
the Chief Counsel, NHTSA, at the street address given above, and two 
copies from which the purportedly confidential information has been 
deleted should be submitted to the Docket Section. A request for 
confidentiality should be accompanied by a cover letter setting forth 
the information specified in the agency's confidential business 
information regulation, 49 CFR Part 512.
    Comments on this notice will be available for inspection in the 
docket. NHTSA will continue to file relevant information as it becomes 
available in the docket after the closing date. Those persons desiring 
to be notified upon receipt of their written comments in the Docket 
Section should enclose, in the envelope with their comments, a self-
addressed stamped postcard. Upon receipt, the docket supervisor will 
return the postcard by mail.

    Issued on: May 4, 1999.
L. Robert Shelton,
Associate Administrator for Safety Performance Standards.
[FR Doc. 99-11545 Filed 5-6-99; 8:45 am]
BILLING CODE 4910-59-P