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Interpretation ID: 2743y

Mr. W. C. Glasscock
Sun-Cool & Co.
2201 North Fifth Street
Springfield, Illinois 62702

Dear Mr. Glasscock:

This responds to your letter concerning the installation of aftermarket tinting on motor vehicle windows. According to your letter, you have been involved in the window tinting business for many years but only recently became aware of the fact that Federal law prohibits businesses from adding tinting film to motor vehicle windows if it reduces the level of light transmittance below that required by the Federal standard. You expressed concern that there appears to be a conflict between Federal and state law in this area and that there has been a lack of enforcement of the Federal requirement.

We are pleased that you have become aware of the Federal requirement in this area and that you are apparently now complying with it. As you may have heard, we have brought suit against six tint businesses in Florida. Those cases are pending in Federal court. We also plan to take appropriate steps to enforce the Federal requirement in other parts of the nation.

I will now discuss the relationship between Federal and state law in this area. The National Highway Traffic Safety Administration ("NHTSA") is responsible for issuing Federal motor vehicle safety standards that establish requirements for specific levels of safety performance for new motor vehicles and motor vehicle equipment. Federal Motor Vehicle Safety Standard No. 205, Glazing Materials (49 CFR 571.205), which has been in effect since 1968, imposes a minimum level of light transmittance of 70 percent in all areas requisite for driving visibility (which includes all windows on passenger cars). The purpose of this requirement is to ensure adequate visibility through the windows, thereby reducing the risk of a motor vehicle crash.

Although Federal motor vehicle safety standards apply directly only to new vehicles and equipment, Federal law also imposes limits on the addition of tinting materials to motor vehicle glazing after vehicles have been purchased by consumers. Pursuant to section 108(a)(2) of the National Traffic and Motor Vehicle Safety Act, 15 U.S.C. 1397(a)(2), manufacturers, distributors, dealers, or motor vehicle repair businesses may not "render inoperative" any equipment or element of design installed in compliance with a Federal safety standard. Thus, those businesses may not install tinting that reduces the light transmittance of windows covered by Standard 205 to a level below the Federal requirement of 70 percent, since that would make the windows "inoperative" within the meaning of Standard 205.

You stated that state laws differ from the Federal law, citing as an example an Illinois law which, according to your letter, allows tinting on the rear and sides of vehicles as long as the vehicle's owner has a letter from a physician licensed to practice in the state of Illinois that explains the medical basis for the need.

The "render inoperative" provision of Federal law does not apply to actions by individual vehicle owners. Therefore, each State may regulate the extent to which after market tinting may be applied by vehicle owners to their own vehicles.

However, no state has the authority to grant any exemptions from the "render inoperative" prohibition of Federal law that applies to commercial entities. Hence, regardless of any provisions of state law, no manufacturer, distributor, dealer, or motor vehicle repair business may legally install window tinting film on a vehicle, unless the vehicle continues to comply with the Federal light transmittance requirements.

I hope this information is helpful.


Paul Jackson Rice Chief Counsel

ref:205 d:ll/9/90