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Mr. Steve Brookmire
Sport Utility Accessory Depot
1945 Airport Court, Suite B
Marietta, GA 30062

Dear Mr. Brookmire:

This responds to your letter requesting information about the impact of brush guards and grille guards on the Nissan Pathfinder air bag assembly. Your company is a distributor of brush guards and grille guards. You indicate in your letter that Nissan has stated the installation of these products may interfere with the air bag. This letter will address the effect under Federal laws of the installation of a bumper guard or grille guard.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) is authorized under 49 U.S.C. section 30101 et seq. to issue Federal motor vehicle safety standards that apply to the manufacture and sale of new motor vehicles and new items of motor vehicle equipment. Federal law prohibits any person from manufacturing, introducing into commerce, selling, or importing any new motor vehicle or item of motor vehicle equipment unless the vehicle or equipment is in conformity with all applicable safety standards. NHTSA does not approve motor vehicles or motor vehicle equipment, nor do we endorse any commercial products. Instead, each manufacturer is responsible for "self-certifying" that its products meet all applicable safety standards.

NHTSA has exercised its authority to establish standard No. 208, Occupant Crash Protection (49 CFR Part 571.208). Among other things, Standard No. 208 requires that cars be equipped with automatic crash protection. "Automatic crash protection" means that a vehicle is equipped with occupant restraints that require no action by vehicle occupants. Standard No. 208 applies to new vehicles; therefore, if a brush guard or grille guard is installed by the manufacturer before the vehicle's first purchase for purposes other than resale, the vehicle manufacturer would have to certify that the vehicle complied with all applicable standards, including Standard No. 208, with the brush guard or grille guard installed.

After the first purchase of a vehicle for purposes other than resale, the only provision in Federal law that affects the vehicle's continuing compliance with an applicable safety standard is set forth in 49 U.S.C. section 30122. That section provides that:

A manufacturer, distributor, dealer, or motor vehicle repair business may not knowingly make inoperative any part of a device or element of design installed on or in a motor vehicle or motor vehicle equipment in compliance with an applicable motor vehicle safety standard.

Any violation of this provision would subject the violator to a potential civil penalty of up to $1,100 for each violation. This provision would prohibit a commercial business from installing a brush guard or grille guard on a vehicle equipped with an air bag in a manner that would negatively affect the vehicle's compliance with Standard No. 208 or any other safety standard.

Please note that this provision would apply to a vehicle manufacturer, distributor, dealer, or repair business installing the product and not to the company that manufactures or distributes the product. Also note that this provision does not apply to modifications vehicle owners make to their own vehicles. Thus, Federal law would not apply in situations where individual vehicle owners install a brush guard or grille guard on their own vehicles, even if the installation were to result in the vehicle no longer complying with the safety standards. However, States have the authority to regulate modifications that individual vehicle owners may make to their own vehicles.

You should also note that a brush guard or grille guard would be considered "motor vehicle equipment" under Federal law. Therefore, if it contained a defect (either in manufacture, design, or performance) that relates to motor vehicle safety, the guard manufacturer would be required to conduct a recall campaign to notify owners and to remedy the defect free of charge.

It is not possible for NHTSA to provide an unequivocal opinion as to whether brush guards or grille guards will interfere with air bag performance. This is because any answer would depend on the designs of the guards, the air bag, and the vehicle as a whole. The discussion which follows illustrates possible problems, identified by our technical staff, which brush guards or grille guards could cause with respect to air bags. Please understand that these examples do not represent the universe of possible problems.

First, a guard attached to the bumper could possibly induce unwarranted air bag deployments if the guard extended vertically below the car bumper. Such a guard could snag on travel surface irregularities, sharp inclines, or sharp incline departure angles which might otherwise not engage the vehicle structure.

Second, if a guard were attached to the vehicle structure, rather than the bumper, it too could possibly produce deployments that are not intended. Such a system might impose direct loading into the vehicle frame without the energy absorption of the bumper moderating the impulse experienced by the crash sensor system which is calibrated to measure crash severity.

Third, if a guard were added to the front bumper of a vehicle in such a manner as to change the load path through the bumper of the car structure behind the bumper, it is possible that the crash impulse arriving at the crash sensor location might be different from the impulse that would be present without the guard, causing air bag deployment to occur either above or below the original manufacturer's deployment threshold, and at a different time during the crash.

I hope you find this information helpful. If you have any other questions, please contact Rebecca MacPherson of my staff at this address or by phone at (202) 366-2992.

John Womack
Acting Chief Counsel