Interpretation ID: aiam3133
Group Director-Engineering
Bendix Corporation
901 Cleveland Street
Elyria
OH 44035;
Dear Mr. Hildebrandt: This responds to your September 20, 1979, letter asking the Nationa Highway Traffic Safety Administration (NHTSA) to give you written confirmation that your tandem axle trailer brake system complies with Standard No. 121, *Air Brake Systems*.; The NHTSA does not provide advance determinations of compliance wit the agency's safety standards. It is the manufacturer's responsibility to test for and certify the compliance of its vehicles or equipment. The agency cannot always tell by diagrams and word descriptions whether a system will or will not comply with applicable safety standards. Compliance of a braking system, such as yours, can only be determined when tested on a completed vehicle.; Our technical staff has reviewed the diagrams and the letter that yo submitted. In their opinion, your system appears to comply with the requirements of the standard. However, this is merely an opinion based upon your submission and does not bind the agency in any way should your device fail any compliance tests conducted by the agency.; Sincerely, Frank Berndt, Chief Counsel