Interpretation ID: nht92-9.29

DATE: February 3, 1992

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Harvey D. Benson -- Chief Engineer, Landoll Corporation

TITLE: None

ATTACHMT: Attached to letter dated 12/5/91 from Harvey D. Benson to Richard Carter (OCC 6764)

TEXT:

This responds to your letter to Mr. Richard Carter of this agency asking about requirements applicable to heavy hauler trailers. You first asked whether such trailers were required to be equipped with spring brakes. You stated that some users of your vehicles have received tickets for not having spring brakes. Your second question asked whether there are requirements about size and impact capacity for bulkhead (i.e., cab protection) on truck chassis beds. You explained that Landoll manufactures slide back beds mounted on single and tandem axle truck chassis. I am pleased to have this opportunity to explain our requirements.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not provide approval of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act ("Safety Act"), the manufacturer is responsible for certifying that its vehicles or equipment comply with applicable standards. The following letter represents our opinion based on the facts presented in your letter.

The Safety Act requires NHTSA to promulgate motor vehicle safety standards that specify performance requirements for motor vehicles and motor vehicle equipment. One such safety standard is Standard No. 121, Air Brake Systems, (49 CFR 571.121) which specifies requirements for braking systems on vehicles equipped with air brake systems, including most trailers. In particular, section S5.6 specifies requirements for parking brakes. This section states that the trailer portion of a heavy hauler trailer is required to meet the requirements of section S5.6 or at the manufacturer's option the requirements set forth at 49 CFR S393.43, Breakaway and Emergency Braking (a regulation issued by the Federal Highway Administration (FHWA)).

Spring brakes are used by most manufacturers to comply with the parking brake requirements in S5.6 of Standard No. 121. However, those requirements can be met by other types of brake designs. In addition, as mentioned above, a heavy hauler trailer as defined in S4 of the standard is permitted to comply with the requirements set forth in 49 CFR S393.43.

You mentioned that your trailers have capacities up to 120,000 GVWR. Please be advised that Standard No. 121 applies to such vehicles; however, the standard does not apply to trailers that have both a GVWR of more than 120,000 pounds and bodies that conform to the definition for "heavy hauler trailer" set forth in S4.

As for your comment that some of your customers are being ticketed for not having spring brakes, I do not have sufficient information to address this situation. If you would like us to look into this matter, please provide details concerning specific instances of such ticketing, including the agency responsible for the ticketing and the regulation being applied.

As for your second question about requirements for bulkhead cab protection on truck chassis beds, NHTSA has no regulations about this topic. However, you should review the FHWA's Federal Motor Carrier Safety Regulations, which set forth specific requirements for bulkhead protection in commercial motor vehicles. (49 CFR Part 393.106.)

I hope this information is helpful. If you have any further questions about NHTSA's safety standards, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992. If you have questions about the FHWA's in-use requirements, you should contact its Office of Motor Carrier Safety at (202) 366-1790.