Mr. Randy W. McGuire
    Vice President of Engineering
    Fontaine Trailer Company
    P.O. Box 619
    Haleyville, AL 35565

    Dear Mr. McGuire:

    This is in reply to your letter of September 17, 2002, asking for an interpretation of Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment.

    You requested this interpretation in the context of rear lighting equipment on three flatbed trailers depicted in its manufacturers sales brochure, which you enclosed. The aspect of the rear lighting that is the basis of your first question is the array of five identical lamps that appear in the center of the rear of two trailers below the uppermost of the two horizontal conspicuity treatments extending across the width of the trailer. You asked whether this arrangement is considered to comply with Standard No. 108.

    The answer is no. Tables I and II of Standard No. 108 requires that motor vehicles including trailers with an overall width of 2032 mm (80 inches) or more be equipped with systems of front and rear identification lamps. Each system consists of three amber or red lamps with lamp centers spaced not less than 6 nor more than 12 inches apart. Thus, an identification lamp system complying with Standard No. 108 cannot have more than three lamps. You have correctly interpreted Standard No. 108 to your prospective customers who have expressed an interest in having an array of more than three such lamps. Even if we were to regard the center three lamps as a conforming system of identification lamps, the two lamps on each side of the three-lamp array would be considered additional lighting equipment and prohibited by S5.1.3 of Standard No. 108. S5.1.3 allows additional lighting equipment only if it does not impair the effectiveness of required lighting equipment. In this instance, the two additional lamps would impair the effectiveness of the three-lamp identification system, which is intended to provide an unambiguous indication of the presence of a wide vehicle on the roadway.

    You have asked several questions relating to S5.7, Conspicuity Systems. The first that we shall answer is: "Would the lights all along the horizontal be deemed as a suitable alternative to having full-length reflective tape."

    S5.7 provides only two alternatives for compliance: the use of either retroreflective tape or reflex reflectors. The use of lamps alone on the horizontal member would be a noncompliance with S5. Although you stated that "in some instances the lights are all along the horizontal member," in none of the three rear end configurations shown in the sales brochure are lamps deployed across the rear underride protection device.

    As a foundation for the remaining two questions, you stated your understanding that S5. requires "a piece of reflective sheeting full width across the horizontal member of a rear underride protection device." This is correct; however the requirement is in S5., not (a). You first asked "Would . . . use of lights on the horizontal member be deemed a noncompliance?"

    Standard No. 108 is very specific about the types of lamps, reflective devices, and associated equipment that may be used as original equipment on a motor vehicle. It specifies location, color, and, in the case of conspicuity treatment, the dimensions of the retroreflective sheeting. S5. requires that conspicuity treatment be applied "full width across the horizontal member of a rear underride protection device."The interruption of the conspicuity treatment by the array of five lamps, in our view, would create a noncompliance with S5.7.1.4,1(c). In addition, each of the three trailers is equipped with two vertical metal strips, each of which bisects a segment of white retroreflective sheeting. This also, we believe, creates a noncompliance with S5.

    It is also your understanding that S5.7.1.3(b) "requires that no white sheeting shall be located closer than 75 mm to the edge of any luminous lens area of any red or amber lamp that is required by the standard." Your understanding is correct, but the requirement appears in S5.7.1.4(b). You also asked:"Would the lights used in combination with the reflective sheeting be compliant even though the white sheeting is directly adjacent to the red lamps?"

    The restriction of S5.7.1.4(b) applies only if the red or amber lamp is required by Standard No. 108. The lower array of five lamps is not lighting equipment required by Standard No. 108. As noted above, the array interrupts the conspicuity sheeting, and, in our view, would create a noncompliance with S5.

    I hope that this responds to your questions.


    Jacqueline Glassman
    Chief Counsel