Interpretation ID: nht73-3.13

DATE: 01/22/73

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Wesbar Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of January 3, 1973, to Mr. Schneider concerning Motor Vehicle Safety Standard No. 108.

Your first question is whether the standard requires items of lighting equipment to be marked according to SAE Standard J759a. The answer is no. A manufacturer, at his option, may mark equipment items with the symbol DOT as a certification of compliance with Standard No. 108. Standard No. 108 neither prohibits nor requires other marking of equipment. The NHTSA proposed in 1972 that equipment be marked in a manner somewhat similar to J759a but no definitive action has been taken on the proposal.

You also asked whether a clearance lamp could be mounted at 45 degrees to serve the functions of both a clearance and side marker lamp, and whether it must bear the SAE designation "PC" indicating its combination function. Your understanding is correct, that a combination lamp mounted at 45 degrees is permissible if it is successfully tested at that mounting angle for conformance to both clearance and side marker requirements. The designation "PC" is not a current requirement of Standard No. 108 but has been proposed as the required marking symbol in the rulemaking action referred to earlier.