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Interpretation ID: nht94-7.3

DATE: April 5, 1994

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Scott Slaughter -- Pitts Enterprises, Inc. (Pittsview, AL)

TITLE: None

ATTACHMT: Attached to letter dated 2/2/94 from Scott Slaughter to Marv Shaw (OCC 9654)

TEXT:

This responds to your inquiry about whether a logging trailer known as the "knuckle boom loader trailer" that you manufacture is a motor vehicle that would have to comply with the applicable Federal Motor Vehicle Safety Standards. You explained that your trailer stays in the woods the majority of its life and is infrequently transported over public roads between job sites. I am pleased to have this opportunity to explain our regulations to you.

This agency interprets and enforces the National Traffic and Motor Vehicle Safety, Act ("Safety Act" 13 U.S.C. S 1392 et seq.) under which the Federal Motor Vehicle Safety Standards are promulgated. The 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."

Whether the agency considers your trailer to be a motor vehicle depends on its use. 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 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 the Safety Act, since the on-highway use is more than "incidental."

Based on the available information, it appears that your trailer is not a "motor vehicle" within the meaning of the Safety Act. This conclusion is based on statements in your letter and brochures that this equipment spends extended periods of time at a single construction site and only uses the public roads infrequently to move between job sites. Thus, the agency would consider the use of your device on the public roads to be incidental and not its primary purpose. Since your trailer is not a motor vehicle, it would not be subject to our Federal Motor Vehicle Safety Standards.

If the agency were to receive additional information indicating that your trailer used the roads more than on an incidental basis, then the agency would reassess this interpretation. If the agency were to determine that your trailer is a motor vehicle, then the trailer would have to comply with the applicable Standards, including Standard No. 108 Lamps, Reflective Devices, and Associated Equipment, which addresses conspicuity, Standard No. 115, Vehicle

Identification Numbers, Standard No. 120, Tire Selection and Rims for Motor Vehicles Other Than Passenger Cars, and Standard No. 121 Air Brake System which requires automatic slack adjusters and brakes to act on all wheels.

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.