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Interpretation ID: Lorenz2

Mr. Steffen Lorenz

Webasto AG

Kraillinger Straβe 5

D-82131 Stockdorf

Germany

Dear Mr. Lorenz:

This responds to your e-mail in which you requested confirmation as to the permissibility of your sunroof design under our regulations, specifically one incorporating a number of solar cells intended to power a ventilator to help cool the occupant compartment. As shown in the attachment to your e-mail, we understand that your company intends to produce a sunroof with Item 2 glazing, which is tempered by a glazing manufacturer according to the specifications of the American National Standard for Safety Glazing Materials for Glazing Motor Vehicles and Motor Vehicle Equipment Operating on Land Highways Safety Standard ANSI Z26.1 (ANSI Z26.1) and which exhibits light transmissibility of greater than 70 percent. You further stated that crystalline solar cells enveloped in a laminate film would then be attached to the inner side of the glass panel, which would effectively diminish the light transmissibility of the glazing to zero percent. In addition, you stated that the sunroof design is such that the sunshade is affixed to the glass panel, thereby preventing occupants from touching the glass/laminate portion of the sunroof from the inside of the vehicle. Although we have not had the opportunity to examine your product in operation, from the information provided in your letter, we are of the opinion that it would be permissible, so long as it meets the applicable requirements of our safety standard on glazing materials. As discussed below, placement of opaque solar cells on the sunroof would not be prohibited, because there are no light transmittance requirements for sunroofs, since roof glazing is not in an area requisite for driver visibility.

By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue Federal motor vehicle safety standards (FMVSSs) that set performance requirements for new motor vehicles and items of motor vehicle equipment. To clarify, NHTSA does not provide approvals of motor vehicles or motor vehicle equipment, nor do we issue permits. Instead, it is the responsibility of manufacturers to certify that their products conform to all applicable safety standards before they can be offered for sale. The requirements concerning vehicle certification may be found at 49 CFR Part 567, Certification, and for items of glazing themselves, a prime glazing manufacturer certifies its glazing by marking it with the symbol DOT and the manufacturers code mark assigned by NHTSA (see 49 CFR 571.205 S6). NHTSA enforces compliance with the standards by purchasing and testing vehicles and equipment, and we also investigate safety-related defects.

Of particular relevance here, FMVSS No. 205, Glazing Materials, specifies, inter alia, strength and light transmittance performance requirements for various types of glazing used in motor vehicles, including sunroof applications. As you are aware, FMVSS No. 205 incorporates by reference ANSI Z26.1. Accordingly, prior to sale, a manufacturer must certify compliance of its product with the requirements of FMVSS No. 205, including those requirements incorporated from ANSI Z26.1.

Turning to the specifics of your sunroof design, we would first note that under FMVSS No. 205, Item 2 glazing is permitted to be used anywhere in the vehicle except the windshield, provided that it meets the relevant requirements incorporated under ANSI Z26.1. In order to sell the glazing or incorporate it in a new vehicle offered for sale in the United States, the manufacturer must self-certify that the glazing complies with Standard No. 205. As to placement of solar panels on the sunroof glazing, the standard would not prohibit such an application. FMVSS No. 205 contains no light transmittance requirements applicable to your glass sunroof because roof glazing is not in an area requisite for driver visibility.

If you have any further questions, please feel free to contact Eric Stas of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

Anthony M. Cooke

Chief Counsel

ref:205

d.10/17/06