Interpretation ID: 2840o
Vice President
General Sales Manager
Wesbar Corporation
P. O. Box 577
West Bend, WI 53095
Dear Mr. Nielsen:
This is in reply to your letter of February 17, 1988, asking for an interpretation of paragraph S4.l.l.7 of Motor Vehicle Safety Standard No. 108, which applies to turn signal lamps. In pertinent part this section requires turn signal lamps for vehicles whose overall width is 80 inches or more to "have an effective projected luminous area not less than 12 square inches." Your design has a lens area of 12 square inches incorporating an integral Class A reflex reflector, and you have asked whether you may include the "illuminated (by the turn signal bulb) reflex reflector portion of the turn signal lens" in your calculation.
We assume from your letter that the light shines through the reflector when the turn signal is activated, and that the reflector is not opaque. In this instance, the reflector area may be included as part of "the effective projected luminous area" within the meaning of S4.l.l.7.
I hope that this answers your question.
Sincerely,
Erika Z. Jones Chief Counsel
ref:108 d:3/l6/88