Interpretation ID: nht72-2.40

DATE: 07/19/72

FROM: AUTHOR UNAVAILABLE; C. A. Baker for E. T. Driver; NHTSA

TO: Raybestos-Manhattan

TITLE: FMVSS INTERPRETATION

TEXT: In your letter of June 30, 1972, you raised two questions that touch on the responsibility of manufacturers who produce components, such as brake blocks, that affect the ability of a vehicle to meet a motor vehicle safety standard.

Motor Vehicle Safety Standard No. 121, Air Brake Systems, the standard of concern to you, regulates vehicles equipped with air brakes, but it does not regulate the brakes or their components as separate items of equipment. As a component manufacturer, your company is therefore not required by our regulations to certify its products as conforming to Standard 121. This is not to say that your customers will not be concerned about the performance of your products, but only that you have no direct responsibility under the standard.

A vehicle manufacturer who intends to use your brake blocks on a new vehicle will probably try to get as much test data from you as he can. His vehicle will have to conform to the standard. If our tests disclose a shortcoming in the brakes, he will have to show that he exercised due care in the manufacture of the vehicle and the data he obtains from you may be an important part of his case. Whether you supply him with dynamometer data or complete road test data is a matter to be arranged privately, however, and the subject is not regulated by our rules.

A brake block or other brake component sold as a replacement part is not at this time subject to regulation under Standard 121. A truck owner will presumably want to obtain components that are compatible with the rest of the brake system.

You have also asked for information about agencies equipped to run tests in accordance with Standard 121. At this time we have not compiled a list of test facilities, but we expect that such information will become widely available in the next few months.