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10-004510ws Savidge









Keith A. Savidge, Esq.

Seeley, Savidge, Ebert & Gourash Co., LPA

26600 Detroit Road

Cleveland, Ohio  44145

Dear Mr. Savidge:

This responds to your letter dated June 25, 2010, asking whether the SM Series Trommels distributed by your client, Doppstadt US, are motor vehicles regulated by the National Highway Traffic Safety Administration (NHTSA).  Our answer is no.

By way of background, NHTSA is authorized by the National Traffic and Motor Vehicle Safety Act (49 U.S.C. Chapter 301, Safety Act) to issue Federal motor vehicle safety standards (FMVSSs) that set performance requirements for new motor vehicles and new items of motor vehicle equipment.  NHTSA does not provide approvals of motor vehicles or motor vehicle equipment.  Instead, manufacturers are required to self-certify that their products conform to all applicable safety standards that are in effect on the date of manufacture.  NHTSA selects a sampling of new vehicles and equipment each year to determine their compliance with applicable FMVSSs.  If our testing or examination reveals an apparent noncompliance, we may require the manufacturer to remedy the noncompliance, and may initiate an enforcement proceeding if necessary to ensure that the manufacturer takes appropriate action.  NHTSA also investigates safety-related defects.

The following is our interpretation of the FMVSSs based on the description in your letter.

You state that the SM Series Trommels are non-self-propelled separators of forestry and other recycled products.  You further state that the trommels do not move under their own power and are only periodically towed on public roads for use in other locations.  Finally, you state that the majority of units remain at a single location during their entire operating lifetime.  The websites of Doppstadt US,, and the manufacturer Doppstadt,, indicate that the trommels are available with dual-axle or tracked chassis.  These websites[1] also indicate that some of the trommels are capable of self-propelled drive but that this feature is intended only for movement at the jobsite.


The Safety Act (49 U.S.C. Section 30102(a)(6)) defines a 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.

If a vehicle is a motor vehicle under the above definition, then it is regulated by NHTSA and must, among other things, comply with all applicable FMVSSs. 

Whether the agency considers your work units to be motor vehicles depends on the use of the vehicles.  In past agency interpretations, we have determined that vehicles which are primarily used off-highway and which only incidentally use the highways (to move between jobsites) are not motor vehicles under the Safety Act.  An example of this is mobile construction equipment which use the highway only to move between jobsites and which typically spend extended periods of time at a single jobsite.  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.  

However, certain types of construction equipment make more frequent use of the roadways, and the agency has determined that such equipment are motor vehicles under the Safety Act.  For example, dump trucks have been determined to be motor vehicles because they regularly use the highways to travel between jobsites and stay on such jobsites for only a limited period of time, thereby rendering their on-highway use more than incidental.

In past interpretations, we have determined that certain types of trommels and other screening equipment are not motor vehicles under the Safety Act.  (See enclosed copies of April 26, 1993 letter to Mr. Jeff Gerner, and December 1, 1998 letter to Mr. Thomas W. Allison.) 

Based upon the depictions of the SM Series Trommels from the information you provided and the relevant websites, it appears that the units are designed to be primarily used at off-road jobsites for extended periods of time, but may occasionally be towed on highways from one jobsite to another.  Thus, the on-highway transport of these units appears to be merely incidental to their use on jobsites.  Based on the above information, we do not believe that the SM Series Trommels are motor vehicles under the Safety Act.

This determination is based on the information provided.  If in fact the units are using the roads and highways more than on an incidental basis, then the agency would reassess this interpretation. 


I hope this information is helpful.  If you have further questions, please contact William Shakely of my staff at (202) 366-2992.




                                                                                    O. Kevin Vincent

                                                                                    Chief Counsel



[1] We last accessed these websites October 12, 2010.