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Federal Motor Vehicle Safety Standards; Air Brake Systems--Control Line Pressure Balance

American Government Special Collections Reference Desk

American Government Trucking Topics:  National Highway Traffic Safety Administration, Federal Motor Vehicle Safety Standards

Federal Motor Vehicle Safety Standards; Air Brake Systems--Control Line Pressure Balance

Barry Felrice
Federal Register
January 19, 1994

[Federal Register: January 19, 1994]



National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. 85-07; Notice 8]
RIN 2127-AD27

Federal Motor Vehicle Safety Standards; Air Brake Systems--
Control Line Pressure Balance

AGENCY: National Highway Traffic Safety Administration (NHTSA), 
Department of Transportation.

ACTION: Denial of petition for reconsideration.


SUMMARY: This notice denies a petition submitted by Mr. Robert Crail 
requesting the agency to reconsider a final rule that added control 
line pressure balance requirements to the pneumatic timing requirements 
applicable to air brake systems. Mr. Crail's petition was based on his 
allegations that NHTSA had not adequately considered the added costs to 
trailer manufacturers imposed by the rulemaking, including the hardware 
costs to achieve compliance with the new control line pressure balance 
requirements and the costs associated with certifying compliance with 
those requirements. In response to this petition, the agency has 
reexamined the final rule's evaluation of additional costs for this 
requirement and again concludes that those additional costs are not 
excessive or unreasonable. Therefore, Mr. Crail's petition is denied.

Mr. Richard C. Carter, Office of Vehicle Safety Standards, National 
Highway Traffic Safety Administration, 400 Seventh Street, SW., 
Washington, DC 20590 (202-366-5274).

SUPPLEMENTARY INFORMATION: On August 21, 1992, NHTSA published a final 
rule amending the pneumatic timing requirements of Standard No. 121, 
Air Brake Systems, with respect to the control line pressure balance 
for tractor trailer combinations (57 FR 37902). In that notice, the 
agency adopted a dynamic test procedure for determining the control 
signal pressure differential.
    In comments to the notice of proposed rulemaking (NPRM) that 
preceded this final rule, Mr. Crail and the Truck Trailer Manufacturers 
Association (TTMA) stated that they believed that measuring control 
line pressure balance in a dynamic test instead of in a static test 
would result in excessive costs. Mr. Crail, who is employed by a 
trailer manufacturer, stated that the total cost of a dynamic test 
would be approximately $6,000, as compared to his estimated cost of 
$900 for a static test. Similarly, TTMA believed that a dynamic test 
procedure would require trailer manufacturers to purchase expensive 
equipment, such as transducers and recording equipment, costing as much 
as $6,000. TTMA estimated that the static test apparatus would cost 
about $300 per manufacturer.
    Notwithstanding these comments, NHTSA adopted a dynamic test 
procedure to evaluate control line pressure differential in the August 
1992 final rule. The agency concluded that the static control line 
pressure differential test advocated by Mr. Crail and TTMA would not 
adequately evaluate the pressure differential problem. The agency also 
determined that the costs associated with the new dynamic test were 
reasonable and would be well below the levels estimated by Mr. Crail 
and TTMA. The agency explained this determination as follows:

    The agency notes that most trailer manufacturers already own the 
most expensive portion of this test equipment for conducting timing 
tests (i.e., the data recorder/power supply/signal conditioning 
apparatus), and that the mini-tractor test rigs that are currently 
used in compliance testing with Standard No. 121 could be readily 
upgraded to check for pressure differentials for an additional cost 
of $300. Of this cost figure, $100 would cover the hose, gladhands, 
and air flow restrictor and $200 would cover the cost of upgrading 
the software of the test rig. NHTSA notes that the practical effects 
of these requirements are limited to only those trailer 
manufacturers who build towing trailers (i.e., trailers used in 
doubles or triples operations). Such towing trailers currently 
constitute a very small percentage of the trailer market. 57 FR 

    In short, the agency concluded that most trailers would not be 
subject to the new dynamic test for control line pressure balance and 
those that were would face added costs of about $300.
    Mr. Robert Crail filed the lone petition for reconsideration of 
this rule. Mr. Crail stated that the agency did not adequately consider 
the cost impact that would be imposed on trailer manufacturers to equip 
trailers with new hardware necessary to achieve compliance with the new 
requirements. The petitioner also believed that NHTSA did not 
adequately consider the cost impact on manufacturers to obtain or adapt 
test equipment to test trailers for compliance with the new 
requirements. The agency will address each of these assertions in turn.

Relay Booster Valves

    In his petition for reconsideration, Mr. Crail contends that NHTSA 
seriously underestimated the cost impact per trailer of adding 
additional equipment to comply with the final rule. According to Mr. 
Crail, trailer manufacturers could comply with Standard 121 prior to 
this amendment without incorporating a relay booster valve on their 
trailers. However, again according to Mr. Crail, the August 1992 final 
rule in effect requires the use of relay booster valves on trailers. 
Mr. Crail estimates that the cost to the trailer manufacturer to add 
these valves would range from $26 to $54.
    NHTSA believes that Mr. Crail's initial assertion about a trailer's 
ability to comply with Standard 121 without incorporating a relay 
booster valve on trailers is incorrect. The agency notes that the 
majority of trailers required a relay booster valve to comply with the 
requirements adopted on May 3, 1989 (54 FR 13890, 85-07, Notice 3). 
However, the control line pressure requirements of the August 1992 
notice did not have the effect of requiring that an additional valve be 
added to the system. The August 1992 requirements only required that 
valves used to comply with the May 1989 requirements did not induce 
unwanted pressure differentials. Therefore, NHTSA believes that the 
amendment in question did not have the effect of requiring a relay 
booster valve where none was required before.

Other Hardware Costs

    NHTSA further believes that Mr. Crail's assertions about the 
rulemaking's hardware costs are incorrect.
    The agency considered these same assertions about hardware costs 
when it was developing the August 1992 rule. In that rule, NHTSA 
indicated that some manufacturers might have to use higher quality 
relay valves than they presently use to meet the requirements, but that 
these higher quality valves are not significantly more expensive. In 
addition, the agency acknowledged that manufacturers may have to modify 
existing valve designs to control pressure differential. However, the 
agency estimated that such modified valves would cost only a few 
dollars more per trailer. Moreover, the final rule also indicated that 
these upgraded valves would only be needed on towing trailers. The 
total annual production of towing trailers is roughly 21,400. 
Therefore, the agency concluded that the aggregate costs for additional 
equipment on all trailers to comply with the control line pressure 
balance requirements would be relatively small.
    In its review of Mr. Crail's petition for reconsideration, NHTSA 
once again reviewed the hardware costs associated with the control line 
pressure balance requirements. The agency concludes that valves that 
would be needed to meet the August 1992 rule are not significantly more 
expensive that those used prior to the rule. To illustrate, Bendix, a 
valve manufacturer, has designed a new valve that it advertises as 
complying with these new requirements. These valves actually cost less 
than valves previously used in trailers to control for pressure 
balance. Accordingly, NHTSA continues to believe that its initial 
determination that the hardware costs associated with the rulemaking 
are not unreasonable is correct.

Testing Costs

    Mr. Crail also asserted that the agency seriously underestimated 
the costs to trailer manufacturers for testing compliance with the new 
dynamic test procedure. As noted above, NHTSA stated in the final rule 
that the mini-tractor test rights that are currently used to test 
compliance with other requirements in Standard No. 121 could be readily 
upgraded to check for pressure differentials at an added cost of about 
$300. Mr. Crail asserted that, on top of the $300 costs estimated by 
NHTSA, there would be nearly $5900 of additional costs to record the 
pressure data collected during the prescribed test. The $5900 estimate 
consisted of two sets of pressure transducers and cables, at a cost of 
$600 per set, a strip chart recorder, at a cost of about $4000, and 
approximately $700 in labor costs.
    Mr. Crail also stated that trailer test rigs commonly used by 
trailer manufacturers cannot be simply adapted to the additional tasks 
of recording pressure tracers simultaneously at both the trailer's 
input and delivery gladhands, as the agency suggested in the preamble 
to the final rule. Instead, Mr. Crail asserted that manufacturers would 
have to equip the test rig with at least three additional pressure 
transducers and a recording device capable of three channel input.
    NHTSA disagrees. Through tests conducted at the Vehicle Research 
and Test Center (VRTC) and conversations with a Gooch Brake and 
Equipment Company, a manufacturer of mini-tractor test rigs, NHTSA 
concludes that trailer manufacturers need not equip their test rigs 
with additional pressure transducers and a recording device costing 
approximately $5900. As explained in the final rule, most trailer 
manufacturers use test rigs, known as ``variables'' test equipment, for 
a variety of timing and pressure testing of vehicles in certifying 
compliance with Standard No. 121. Therefore, a manufacturer typically 
will not have to procure test equipment solely to comply with the new 
rule. Rather, most manufacturers can easily upgrade their current test 
rig to evaluate the pressure differential through the following 
modifications at a cost of about $300: Adding a hose, gladhands, and an 
air flow restrictor, for approximately $100; and upgrading the test 
rig's software, for $200. While it is true that the total cost of 
``variables'' test equipment would be approximately $6000 to $7000, a 
trailer manufacturer that already owns the test rig would incur an 
incremental cost of $300 to comply with this amendment.
    NHTSA further notes that the petitioner's assertions appear to be 
based on a belief that a trailer manufacturer must use the test 
procedure and testing equipment described in Standard No. 121. Such a 
belief is incorrect. The National Traffic and Motor Vehicle Safety Act 
(Safety Act) requires each manufacturer to certify that its vehicles 
meet Standard No. 121. Accordingly, the vehicle must meet the 
applicable requirements of Standard No. 121 when tested by NHTSA 
according to the test procedure specified in the standard. However, the 
Safety Act does not require a manufacturer to use the standard's test 
procedure or specified test equipment. A manufacturer may use a variety 
of means to certify compliance, including, among other things, 
engineering analyses, actual testing, and computer simulations, 
provided that due care is exercised in making its certification. If the 
manufacturer exercised due care, it would not be subject to civil 
penalties for manufacturing and selling a noncomplying vehicle.
    Moreover, a manufacturer need not conduct these operations itself. 
Manufacturers can utilize the services of independent engineers and 
testing laboratories. The can also join together through trade 
associations to sponsor testing or analysis. Another alternative is for 
manufacturers, such as trailer manufacturers, to rely on testing and 
analysis performed by other parties, such as the valve manufacturers. 
Valve manufacturers perform extensive analyses and tests of their 
products and, because they seek to sell those products, have a strong 
incentive to provide their customers (the trailer manufacturers) with 
information that the trailer manufacturer can use to certify the 
vehicle to the applicable standards. For example, Bendix currently 
provides this type of information to vehicle manufacturers regarding 
Bendix's new valve for the new pressure control requirements. Based on 
the above considerations, NHTSA believes that a trailer manufacturer 
can certify compliance with the control pressure differential 
amendments without facing an unreasonable cost burden.
    After reexamining this matter in response to Mr. Crail's petition, 
NHTSA reaffirms its conclusion that the new control line pressure 
balance requirements will result in relatively small costs for trailer 
manufacturers. The agency also believes that its conclusions in the 
final rule are appropriate. Accordingly, the petitioner's request to 
reconsider the amendment to Standard No. 121 is denied.

    Issued on January 12, 1994.
Barry Felrice,
Associate Administrator for Rulemaking.
[FR Doc. 94-1176 Filed 1-18-94; 8:45 am]

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