Interpretation ID: aiam2765
Body Designer
Telsta Group
General Cable Corporation
P.O. Box 666
Westminster
CO 80030;
Dear Mr. Williams: This is in reply to your letter of February 3, 1978, concernin placement of the rear identification lamps on a truck. Because the truck has a mast assembly located on the longitudinal axis of the vehicle and center of the rear axle, you have asked whether the lamps should be mounted 'on the mast as high as possible or on the rear face of the rear floor decking.'; Table II of Federal Motor Vehicle Safety Standard No. 108 requires rea identification lamps to be mounted 'as close as practicable to the top of the vehicle....' If placement on the mast interferes with the operation of the lift, or if the lamp would be easily damaged in that location, that location would not appear to be 'practicable' within the meaning of Standard No. 108, and the deck location would fulfill the practicability requirements.; You have also asked which is more important in locating identificatio lamps: '(1) ...as high as possible on a stationary surface and face the lights toward the rear, or (2) to locate to the most rearward surface and then as high as possible on that surface'. Your first choice is the correct one. The purpose of the three lamp cluster is to identify large and frequently slow moving vehicles under conditions of reduced visibility. Therefore, it is more important for the lamps to be located high than it is for them to be at the rear end of the vehicle, for example, on the cab rather than at the deck end. However, the decision as to what is 'practicable' is initially that of the manufacturer and we have generally found those decisions to be correct.; Sincerely, Joseph J. Levin, Jr., Chief Counsel