Interpretation ID: nht94-8.45

DATE: January 24, 1994

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Jerome Cysewski

TITLE: None

ATTACHMT: Attached to letter dated 10/20/93 from Jerome Cysewski to NHTSA Office of Chief Counsel (OCC-9250)

TEXT:

This responds to your letter asking about the applicability of Federal requirements to two vehicles. I apologize for the delay in our response. According to your letter, one vehicle is a 13,600 pound cement silo that has tandem axles. The second vehicle is a 6,400 pound aggregate batch plant that has a single axle. The cement silo and batch plant are mounted on their own trailers, and are equipped with electric brakes. Each vehicle is pulled by a one ton truck with hydraulic brakes. You also stated that both vehicles are mobile but are designed to be towed for off-the-road set and positioning. I am pleased to have this opportunity to explain our regulations to you.

By way of background information, this agency, the National Highway Traffic Safety Administration (NHTSA), issues Federal motor vehicle safety standards under the National Traffic and Motor Vehicle Safety Act (Safety Act). The Safety Act defines the term "motor vehicle" as follows:

"any vehicle driven or drawn by mechanical power manufactured primarily for use on the public streets, roads, and highways, except any vehicle operated exclusively on a rail or rails." (Section 102(3))

If a vehicle is a motor vehicle under the definition, then the vehicle must comply with all applicable Federal motor vehicle safety standards. However, if a vehicle is not a motor vehicle under this definition, then the vehicle need not comply with the agency's safety standards because such a vehicle is outside the agency's scope of authority.

Whether NHTSA considers a construction vehicle, or similar equipment, to be a motor vehicle depends on the use for which it is manufactured. It is the agency's position that this statutory definition does not encompass mobile construction equipment, such as cranes and scrapers, which use the highway only to move between job sites and which typically spend extended periods of time at a single job site. 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 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 the Safety Act, since the on-highway use is more than "incidental."

Your letter does not provide sufficient information for us to determine the extent to which the two vehicles would use the public roads. Nor can we determine whether the on-highway use of the vehicles would be merely incidental and not the primary purpose for which they are manufactured.

However, you should be able to determine whether the vehicles are considered motor vehicles based on the information set forth above.

If the vehicles are considered motor vehicles under the Safety Act, they would be required to meet all safety standards applicable to trailers. Enclosed is an information sheet which identifies Federal statutes and NHTSA standards and regulations affecting motor vehicle and motor vehicle equipment manufacturers.

I hope this information is helpful. If you have any further questions about NHTSA's safety standards, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992.