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Interpretation ID: nht94-7.45

DATE: March 10, 1994

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Larry R. Lynch -- AT & D Corporation

TITLE: None

ATTACHMT: Attached to letter dated 10/27/93 from Larry R. Lynch to John Womack (OCC-9281)

TEXT:

This responds to your inquiry about how Federal safety standards would apply to the "AeroCon System," a new product being developed by your firm. You state that this product is an air deflector/fairing that provides aerodynamic braking. According to your letter, "By opening doors on the fairing unit, the full force of the relative wind speed is redirected to strike the trailer face, greatly decreasing stopping distance. The pneumatic power required to actuate the system's doors utilizes the auxiliary air system of the tractor." (emphasis in original)

I am pleased to have this opportunity to explain our regulations. I am also enclosing a copy of a fact sheet titled "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment."

By way of background information, the National Highway Traffic Administration (NHTSA) does not provide approvals of motor vehicles or motor vehicle equipment. Under the Safety Act, it is the responsibility of the manufacturer to ensure that its vehicles or equipment comply with all applicable standards. The following represents our opinion based on the facts provided in your letter.

NHTSA does not have any specific regulations about air deflectors or fairings. However, since the AeroCon System "utilizes the auxiliary air system," it could affect a vehicle's compliance with Standard No. 121, Air Brake Systems. That standard applies to almost all new trucks, buses, and trailers equipped with air brake systems.

If the AeroCon System is installed as original equipment on a new vehicle, the vehicle manufacturer is required to certify that, with the device installed, the vehicle satisfies the requirements of all applicable safety standards, including Standard No. 121. (See 15 U.S.C. S1397(a)(1) and 49 CFR Part 567.) If the device is added to a previously certified new motor vehicle prior to its first consumer purchase, then the person who modifies the vehicle would be an alterer of a previously certified motor vehicle and would be required to certify that, as altered, the vehicle continues to comply with all of the safety standards affected by the alteration. 49 CFR S567.7.

If the device is installed on a used vehicle by a manufacturer, distributor, dealer, or motor vehicle repair business, then the installer would not be required to attach a certification label. However, it would have to make sure that it did not knowingly render inoperative, in whole or in part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard. 15 U.S.C. S1397(a)(2)(A). You may wish to

determine whether the AeroCon System adversely affects compliance with any of the requirements in Standard No. 121.

In addition, under the Safety Act, the AeroCon System would be considered an item of motor vehicle equipment. Your company, as a manufacturer of motor vehicle equipment, would be subject to the requirements in S151-159 of the Safety Act concerning the recall and remedy of products with safety related defects. In the event that NHTSA or the product's manufacturer determines that a product that is an item of motor vehicle equipment contains a safety-related defect, the manufacturer is responsible for notifying purchasers of the defective equipment and remedying the problem free of charge.

I hope this information is helpful. If you have any questions about NHTSA's safety standards, please feel free to contact Marvin Shaw at this address or by telephone at (202) 366-2992.