Interpretation ID: 18857.ztv

Edward L. Anderson, PE
Supervisor, Automotive Engineering
Central Automotive Division
Port Authority of New York and New Jersey
Port Authority Technical Center
241 Erie Street
Jersey City, NY 07310-1397

Dear Mr. Anderson:

This is in reply to your fax of September 29, 1998, to Rich Van Iderstine of this agency. You have questioned the compliance of certain dump trucks with the rear lighting requirements of Federal Motor Vehicle Safety Standard No. 108 Lamps, Reflective Devices, and Associated Equipment. Our delay in answering your letter is due, in part, to our reassessment of the issue you raised, and our wish to provide you with the results of that reassessment.

Table II of Standard No. 108 requires, as you note, that clearance lamps on the rear shall be mounted "as near the top as practicable." The Port Authority has bought dump trucks with "both identification and clearance lights mounted below the dump body at chassis level" rather than "at the high rear corners as depicted on the dump truck shown on the [National Highway Traffic Safety Administration (NHTSA)] website." You ask if there is an "exception that we are missing or should we be insisting that manufacturers install their clearance lights as shown."

The only exception is stated in S5.3.1.4 of Standard No. 108, which provides that rear clearance lamps need not meet the requirement of Table II that they be located as close as practicable to the top of the vehicle if the rear identification lamps are mounted at the extreme height of the vehicle. This does not appear applicable to the situation you cite where both identification and clearance lamps are located at chassis level.

The website illustration indicates the preferred location for identification and clearance lamps. However, the determination of the circumstances under which an uppermost location may be "practicable" has been the subject of our review. I enclose a copy of a Federal Register notice published on April 5, 1999, that discusses this issue in full. Heretofore, we have accepted a manufacturer's determination of "practicability" unless it was clearly erroneous. Under our published interpretation, we will no longer defer to a manufacturer's subjective determination of practicability. Instead, as applied to dump trucks, if under all the circumstances, it would be practicable to locate clearance and identification lamps closer to the top of a vehicle than they have been, preferably at the top of the dump truck, the manufacturer must do so.

If you have any questions, you may call Taylor Vinson of this Office (202-366-5263).

Sincerely,
Frank Seales, Jr.
Chief Counsel
Enclosure
ref:108
d.4/16/99