Mr. Howard Magor
Aluminum Body Corporation
1600 W. Washington Blvd.
P.O. Box 40
Montebello, CA 90640

Dear Mr. Magor:

This responds to your request for an interpretation whether your company's special purpose aluminum body enclosures, used to provide security and environmental control for electronic systems, are motor vehicles. As explained below, the answer is no.

Your letter states that your enclosures are designed to protect equipment used for data acquisition, satellite monitoring and launch control, earth links, virtual reality training devices, data transmission, and for ground systems such as telescopes and aircraft landing systems. You state that although the enclosures "utilize a semi-trailer format" and are built with commercial trailer undercarriages, they are "for the most part" designed for use on fixed sites. The enclosures' use on the highway "is only incidental to their primary purpose." You further wrote that the enclosures are usually pre-positioned, and supported by four or more leveling jacks, when on the site. The jacks provide stability for the equipment in the enclosures.

In a telephone conversation with Dorothy Nakama of my staff, you explained that once on a work site, the enclosures tend to stay there for months. Your customers move the enclosures only to get to the next job, which is also usually of long duration. You stated that you are aware of an instance where one of your enclosures was placed at the end of an airport runway for several years.

NHTSA's regulations apply only to "motor vehicles," within the meaning of 49 U.S.C. 30102(a)(6). That section defines "motor vehicle" as:

a vehicle driven or drawn by mechanical power and manufactured primarily for use on public streets, roads, and highways, but does not include a vehicle operated only on a rail line.

Based on your description, we believe that your company's enclosures are not motor vehicles. This is based on the use of the vehicles. The on-highway use of the product is similar to that of mobile construction equipment, such as cranes and scrapers, which the agency has determined are not "motor vehicles." Such equipment typically spend extended periods of time at a single job site and use the highway only to move between job sites. In such cases, the on-highway use of the vehicle is merely incidental and is not the primary purpose for which the vehicle was manufactured. (In contrast are instances where vehicles, such as dump trucks, frequently use the highway going to and from job sites, and stay at a job site for only a limited time. Such vehicles are considered motor vehicles for purposes of NHTSA's statute, since the on-highway use is more than "incidental.") Your enclosures stay on job sites for extended periods of time (usually for months) and only use the highway to move from site to site. Because their use of the highway is merely incidental and is not the primary purpose for which the vehicles were manufactured, the enclosures are not motor vehicles.

Because they are not motor vehicles, your enclosures need not meet the Federal motor vehicle safety standards (49 CFR Part 571), or any other NHTSA regulation. I note that, if the agency were to receive additional information indicating that the enclosures use the roads more than on an incidental basis, then the agency would reassess this interpretation.

Please note that because a State may require equipment such as your enclosures to be registered, you may wish to contact the State in which your product will be sold or used about any State requirements that may apply.

I hope this information is helpful. If you have any questions, please contact Dorothy Nakama at (202) 366-2992.

John Womack
Acting Chief Counsel