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Interpretation ID: 2858o

Mr. Derek Nash
Artech Corporation
2901 Telestar Court
Falls Church, VA 22042

Dear Mr. Nash:

This responds to your letter to the National Highway Traffic Safety Administration (NHTSA) and follows up on the April 1, 1988 telephone conversation with Ms. Hom of my staff in which additional information augmenting your letter was provided. I apologize for the delay in responding.

In your letter, you said that you are refurbishing a type of passenger vehicle that was first produced 20 years ago. Your letter raises questions about Federal requirements for persons modifying used vehicles which I will address in the latter part of this letter and about Federal requirements for the design of the vehicle's chassis.

Before I address your specific questions, I would like to provide some background information on our regulations and safety standards. NHTSA has the authority under the National Traffic and Motor Vehicle Safety Act (copy enclosed) to issue motor vehicle safety standards for new motor vehicles and items of motor vehicle equipment. Manufacturers of new vehicles or equipment must certify that their products conform to all applicable Federal motor vehicle safety standards. NHTSA also has the authority to investigate safety-related defects in motor vehicles and motor vehicle equipment. If a manufacturer or the agency determines that the manufacturer's product contains a safety-related defect, the manufacturer must notify purchasers of the product and remedy the defect free of charge.

It is not clear from the information which you have provided us whether the vehicle you are refurbishing would be treated as a new or used vehicle under the Safety Act. A vehicle with a new body and new chassis would be a new vehicle required to meet the standards in effect on the day that manufacture of the vehicle is completed. A vehicle with a new body and old chassis would be a used vehicle.

Section 108(a)(2)(A) of the Safety Act prohibits manufacturers, dealers, distributors and motor vehicle repair businesses (i.e., persons holding themselves out to the public as in the business of repairing motor vehicles or motor vehicle equipment for compensation) from knowingly rendering inoperative any device or element of design installed on or in a new or used motor vehicle in compliance with an applicable Federal motor vehicle safety standard. This means that any person in the above categories modifying a new or used vehicle must do so in a manner that ensures the continued compliance of the vehicle with applicable safety standards. This prohibition affects vehicles manufactured on or after January 1, l968, the date on which the first Federal safety standards became effective. For instance, a commercial business that installs a new fuel system in a passenger car manufactured on or after January 1, 1968 (the effective date of Standard No. 301) must ensure that the new system at least meets the level of safety performance required of the fuel system originally installed on the vehicle. Persons violating section 108 are subject to potential civil penalties of $1,000 per violation.

In instances in which a new vehicle body is installed on an old chassis, section 108(a)(2)(A) requires that the reassembled vehicle meet the Federal safety standards that had been in effect on the date of manufacture of the vehicle. I have enclosed a copy of a January 14, 1976 letter to Mr. Tom Welland that describes generally the applicability of Federal motor vehicle safety standards to refurbished motor vehicles. Please note that the first situation referred to in the Welland letter addresses the modification of a vehicle by its owner. The prohibition in section 108(a)(2)(A) does not apply to the modifications made by vehicle owners to their own vehicles.

I will now address the questions you expressly posed in your letter. Your first three questions asked:

What relationship between allowable stresses in chassis members and the strength of the material is required (or customary) in the design of a passenger-carrying motor vehicle?

What relationship between static and dynamic load is required (or customary) in design assumptions for a passenger-carrying motor vehicle chassis?

What form or test or measurement is required (or customary) to confirm the results of the calculations?

As Ms. Hom informed you, our safety standards apply to new vehicles and are performance-oriented. NHTSA has not issued any design specifications that directly establish minimum static or dynamic loads for vehicle chassis. These design parameters are established by the manufacturer independently of specific criteria set by the agency and might be available from the original manufacturer of the vehicle you are refurbishing. However, manufacturers of new vehicles are required by NHTSA to determine and specify the gross vehicle and axle weight ratings of their vehicles in the manner set forth in Title 49 of the Code of Federal Regulations, Part 567 of our regulations. I have enclosed a copy of Part 567 for your information.

Chassis manufacturers must be aware, however, of the following two considerations relating to the static and dynamic load capacities of vehicles and NHTSA's regulations. First, because manufacturers of new vehicles must certify that their vehicles will perform to the requirements of all applicable Federal motor vehicle safety standards, manufacturers must ensure that chassis design is compatible with the vehicle's ability to comply. Some of our safety standards specify that the performance of requisite vehicle safety systems will be evaluated in dynamic (i.e., crash) tests which enable the agency to evaluate the synergistic effect of a range of variables on a vehicle's compliance therewith. Manufacturers of new vehicles would therefore have to ensure that the design of the chassis will have no negative effect on their vehicle's compliance with applicable safety standards.

Second, as mentioned above, NHTSA has the authority to investigate safety-related defects in motor vehicles and motor vehicle equipment and to require manufacturers to recall and remedy such defects free of charge. Chassis manufacturers must therefore ensure that their products contain no safety related defects, which might well include a chassis member that is incapable of carrying loads for which it is intended.

Further, the vehicle manufacturer who provides the GVWR and GAWR information required by Part 567 must ensure that the information relating to the chassis static loads is correct.

On a separate matter, your letter also asked about the requirements manufacturers must meet when installing a plastic fuel tank in a motor vehicle. The standard we issued for vehicle fuel system integrity (No. 301) sets performance requirements for fuel systems in new motor vehicles. As with all our safety standards, Standard No. 301 (copy enclosed) specifies the test that the agency will use to evaluate the performance of the requisite safety system (e.g., the fuel system) on new vehicles selected for inclusion in its compliance test program. Manufacturers are not bound, however, to use the tests specified in the safety standards for evaluating the compliance of their vehicles or equipment with our standards. Instead, a manufacturer may test in any manner it chooses, so long as it can show that it has exercised due care in ensuring that its vehicles or items of equipment comply with the applicable Federal requirements.

In addition to the materials described above, I have also enclosed information that provides an overview of Federal requirements applying to manufacturers of new motor vehicles and instructions on how you can obtain copies of NHTSA regulations.

I hope this information is helpful. Please contact my office if you have further questions.

Sincerely,

Erika Z. Jones Chief Counsel

Enclosures ref:VSA#108#301 d:4/29/88