Mr. Edward Mansell
Chief Engineer
Polar Tank Trailer, Inc.
12810 County Road 17
Holdingford, MN 56340-9773

Dear Mr. Mansell:

This is in reply to your letter of October 10, 1995, to Philip R. Recht, former Chief Counsel of this agency. You seek an interpretation of the conspicuity requirements of Motor Vehicle Safety Standard No. 108 as they apply to some Food Grade Tank Trailers (FGTTs).

Paragraph S5. requires conspicuity sheeting to be placed "across the full width of the trailer" and "as close as practicable to not less than 375 mm and not more than 1525 mm above the road surface." You indicate that for many trailers the rear bumper is the closest practicable location (approximately 500 mm), but that, on some FGTTs, the load/unload ports are directly above the center portion of the rear bumper. The hot water to which the bumper is exposed degrades the conspicuity sheeting. "Since installation of sheeting subject to frequent hot water run off is not practicable", you interpret this paragraph to allow the sheeting to be "applied from the extreme ends of the bumper to points no more than 6 inches (150 mm) to the left or right of the area directly below the load/unload area." You also state that "otherwise, the center section of the sheeting should be located on the tank, above the load/unload area."

We believe that this interpretation meets the intent of the standard. Under paragraph S5., the mounting height of the conspicuity material is based upon practicability, but the application "across the full width of the trailer" is absolute. We interpret "across the full width" to mean that the sheeting must cover the entire width of the vehicle, though not necessarily on the same plane or continuously. Thus, mounting above the load/unload area would be acceptable as a practicable location. Generally, the agency defers to a manufacturer's determination of practicability and will not question it if it is not clearly erroneous. It is not the intent of the standard that manufacturers "redesign trailers to redirect the flow of wash water."

You also believe that, for FGTTs which use a cabinet to enclose the load/unload area, "conspicuity sheeting should be

mounted on the cabinet doors to augment the sheeting on the bumper." Although you did not enclose a drawing of this configuration, it appears acceptable. We assume that, when viewed from the rear, the sheeting has the appearance of extending across the full width of the vehicle, even if the section on the cabinet doors is not on the same plane as that on the bumpers. This, too, is acceptable as a manufacturer's determination of practicability.


Samuel J. Dubbin Chief Counsel

ref:108 d:12/1/95