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Interpretation ID: 2526y

Mr. John W. Garringer
158 E. Center Street
Shavertown, Pennsylvania 18708

Dear Mr. Garringer:

This responds to your letter asking whether Federal law permits the installation of tinted plastic film on the bottom of motor vehicle windshields. The purpose of this film would be to reduce glare for the driver and any front seat passengers. I am pleased to have this opportunity to explain how our laws and regulations apply to such a product.

Our agency is authorized under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1381 et seq.; the Safety Act) to issue safety standards applicable to new motor vehicles and new items of motor vehicle equipment. NHTSA, however, does not approve or certify any vehicles or items of equipment, nor do we endorse any commercial products or processes. Instead, the Safety Act specifies that each manufacturer itself must certify that its products meet all applicable safety standards. The agency periodically tests vehicles and items of equipment for compliance with the standards, and also investigates alleged defects related to motor vehicle safety and alleged violations of other statutory provisions.

Pursuant to this authority, NHTSA has issued Standard No. 205, Glazing Materials (49 CFR 571.205), which sets forth performance requirements for windows and other glazing items installed in motor vehicles. Among the requirements set forth in Standard No. 205 are specifications for minimum levels of light transmittance. A minimum of 70 percent light transmittance is required in glazing areas requisite for driving visibility, which includes all windows in passenger cars. In trucks and buses, the windshield and windows to the immediate right and left of the driver and the rearmost window, if the latter is used for driving visibility, are considered to be requisite for driving visibility, and therefore subject to the 70 percent minimum light transmittance requirement.

Your letter did not provide any information on the light transmittance that would be measured through glazing with your Hood Glare product installed on it. The combination of the glazing material and your tinting film must allow at least 70 percent light transmittance to comply with the requirements of Standard No. 205. No manufacturer or dealer would be permitted to install your tinting film on the glazing materials on new vehicles, unless the manufacturer or dealer certifies that the vehicle continues to comply with the 70 percent minimum light transmittance and other requirements of Standard No. 205.

After a vehicle is first sold to a consumer, modifications to the vehicle are affected by section 108(a)(2)(A) of the Safety Act (15 U.S.C. 1397(a)(2)(A)). That section prohibits any manufacturer, dealer, distributor, or repair business from "rendering inoperative" any device or element of design installed in a vehicle in compliance with any safety standard. This provision of the law means that no manufacturer, dealer, distributor, or repair business could install tinting film if the addition of the tinting film to the glazing would result in a light transmittance of less than 70 percent, or otherwise cause the vehicle to no longer comply with the applicable requirements of Standard 205. Violations of this "render inoperative" prohibition can result in Federal civil penalties to the manufacturer, dealer, distributor, or repair business of up to $1000 for each noncomplying installation.

Section 108(a)(2)(A) of the Safety Act does not affect vehicle owners. Hence, vehicle owners themselves may install tinting film or any other product on the glazing of their vehicle, regardless of whether the installation causes the vehicle to no longer comply with Standard No. 205. Individual States have the authority to regulate the operational use of vehicles by their owners, and, therefore, have the authority to regulate or preclude individual owner modifications to the glazing of their vehicles.

I have enclosed an information sheet that summarizes the relationship between Federal auto safety laws and motor vehicle window tinting. I hope this information is helpful. If you have any further questions or need any additional information about this topic, please feel free to contact Dorothy Nakama of my staff at this address or by telephone at (202) 366-2992.


Paul Jackson Rice Chief Counsel


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