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Air Brake Systems; Denial of Petition for Rulemaking

Publication: Federal Register
Agency: National Highway Traffic Safety Administration
Byline: Barry Felrice
Date: 25 May 1995
Subject: American Government • Safety • Trucking

[Federal Register Volume 60, Number 101 (Thursday, May 25, 1995)]
[Proposed Rules]
[Pages 27711-27712]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-12831]



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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
49 CFR Part 571

Air Brake Systems; Denial of Petition for Rulemaking
AGENCY: National Highway Traffic Safety Administration.

ACTION: Denial of petition for rulemaking.

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SUMMARY: This notice denies a petition for rulemaking, submitted by 
Rocky Mountain Technology Engineering Corporation, to require that all 
air braked trailers using adjustable axles be equipped with an 
automatic pneumatic locking device. According to the petitioner, its 
device will ensure that the adjustable axles are automatically locked 
in place while the vehicle is in motion. It will help prevent back 
injuries now reportedly resulting from the misuse of manual systems. 
After conducting its review, the agency has determined that the 
petition should not be granted because measures designed to prevent 
back injuries and the unintended movement of adjustable axles do not 
raise significant safety problems.

FOR FURTHER INFORMATION CONTACT: Mr. Richard Carter, Office of Vehicle 
Safety Standards, National Highway Traffic Safety Administration, 400 
Seventh Street, SW., Washington, DC 20590, (202) 366-65274.

SUPPLEMENTARY INFORMATION: Federal Motor Vehicle Safety Standard 
(FMVSS) No. 121, Air Brake Systems (49 CFR 571.121), establishes 
performance requirements for braking systems on vehicles equipped with 
air brakes. The purpose of the standard is to ensure safe braking 
performance under normal and emergency braking conditions.
    Neither FMVSS No. 121 nor any other FMVSS presently addresses the 
locking of adjustable axles on trailers.1 Such adjustable axles 
are also referred to as slider axles. Adjustable axles can move 
backward and forward on semi-trailers. Such adjustability allows the 
axles to be moved so as to balance the loading on the various axles of 
the trailer. In this way, users of semi-trailers can avoid exceeding 
the weight limit on each axle. The adjustability also allows the 
distance between the coupling and the rear axle to be limited in order 
to improve trailer mobility. Currently, most adjustable axles 
incorporate a mechanical system for locking the axles in place.
     1 The Federal Motor Carrier Safety Regulations (FMCSR) 
issued by the Federal Highway Administration (FHWA) specify that 
``Adjustable axle assemblies shall not have locking pins missing or 
disengaged.'' 49 CFR 393.207.
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    On September 30, 1994, Mr. Larry Wessels, the president of Rocky 
Mountain Technology Engineering Corporation (Rocky Mountain), submitted 
a petition for rulemaking requesting that FMVSS No. 121 be amended to 
require semitrailers with adjustable axles to be equipped with an 
automatic pneumatic locking system. Such a system would be joined to 
the air brake system and would allow automatic retraction of the 
locking pins, provided that the parking spring brakes have been set. A 
video tape accompanying the petition highlighted two principle 
differences between present adjustable axle systems and the one 
described by the petitioner. First, Rocky Mountain's device uses four 
locking pins instead of two. Second, its device engages automatically 
through the use of air pressure, rather than manually through the use 
of lever arms. The petitioner contended that its device would replace 
manual locking systems, which it claimed fail more readily and 
frequently result in back injuries when [[Page 27712]] the driver tries 
to manually retract the pin to adjust the sliding axle. The petitioner 
also contended that its system would more likely ensure that the 
adjustable axles remain in place. Based on its concern, Rocky Mountain 
requested that the agency initiate rulemaking to require this product.
    After reviewing the petition and other available information, NHTSA 
has determined that requiring an automatic locking pin system would not 
prevent injuries and fatalities related to motor vehicle accidents. In 
reviewing its recall and defect investigation files, NHTSA found only 
one agency Engineering Analysis involving adjustable axle assemblies: 
in 1980, the agency opened an investigation based upon six consumer 
complaints involving accidents in which the adjustable assembly 
completely separated from Freuhauf flatbed trailers. The agency 
conducted a number of laboratory and field tests in an attempt to 
dislodge the pins from the frame rails. In none of the tests performed 
over a broad range of conditions was the agency able to dislodge the 
pins. The agency closed this Engineering Analysis without ordering a 
recall, redesign, or any other changes to the manufacturer's product. 
The agency's review of its Office of Defect Investigation's (ODI's) 
Customer Complaint file similarly found no safety problems with respect 
to adjustable axles.
    NHTSA also is concerned that requiring a system like Rocky 
Mountain's could potentially create operational problems, given that it 
would increase the complexity of adjustable axle locking systems. 
Specifically, Rocky Mountain's automatic locking system would add 
approximately 20 additional air couplings, 17 more separate air lines, 
four additional air pistons, one fairly complex control valve, and the 
electrical support system to monitor the position of the pistons along 
with the wiring and lighting to the cab area. As a result, the system's 
reliability must be very good. This is so because when more components 
are added to a system, each component must have a high individual 
reliability rate to maintain the same reliability for the total system 
or vehicle. The mechanical systems are less complex compared with the 
automatic system because they have many fewer parts. However, the 
agency believes that they are capable of performing their intended 
function.
    NHTSA notes that requiring Rocky Mountain's product would result in 
considerable costs. Rocky Mountain indicated that its device would cost 
approximately $100 more than the present manual system. Given that the 
average annual production of trailers is approximately 186,000 units 
and that between 85 percent and 90 percent of trailers have adjustable 
axles, NHTSA estimates that requiring the petitioner's device would 
cost approximately $16 million ($100 x 186,000 x 85 percent) annually.
    Rocky Mountain claimed that its device would prevent injuries 
caused both while the vehicle is in use and while the stationary 
vehicle's axle is being adjusted. Based on its review of safety data, 
NHTSA is aware of few injuries caused by such situations.
    Based on the above considerations, NHTSA has determined that Rocky 
Mountain's petition should be denied. This decision is based in part on 
the fact that there are no test data, other information or analyses to 
substantiate the petitioner's claim that the requested amendment would 
reduce injuries and fatalities associated with motor vehicle accidents. 
Moreover, such a requirement would result in significant costs without 
corresponding benefits.
    In accordance with 49 CFR Part 552, the agency has completed its 
technical review of the petition and determined that there is no 
reasonable possibility that the requested amendment would be issued at 
the conclusion of a rulemaking proceeding. Accordingly, the agency is 
denying the petition.
    Notwithstanding NHTSA's decision to deny Rocky Mountain's petition, 
the agency notes that neither the requirements of FMVSS No. 121 nor 
those of the agency's underlying statute under which the standard was 
issued, prohibit the installation of the petitioner's product; provided 
that if it is installed on a vehicle by a vehicle manufacturer, dealer, 
distributor or repair business, neither the act of installation nor the 
operation of the device makes inoperative any device or element of 
design installed on that vehicle in compliance with FMVSS No. 121.

    Authority: 49 U.S.C. 30103 and 30162; delegations of authority 
at 49 CFR 1.50 and 501.8.

    Issued on: May 19, 1995.
Barry Felrice,
Associate Administrator for Safety Performance Standards.
[FR Doc. 95-12831 Filed 5-24-95; 8:45 am]
BILLING CODE 4910-59-P




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