Director of Engineering
Teledyne Specialty Equipment
P.O. Box 246
Canal Winchester, OH 43110-0246
Dear Mr. Neagle:
We have received your letter of February 1, 1996, asking for an interpretation of the requirements of Federal Motor Vehicle Safety Standard No. 108 with respect to lighting on the rear of trailers.
Your company has developed a new system to attach a transportable forklift to a trailer. When installed on some trailers, "it requires the tail/brake/turn lights to be mounted more toward the center of the trailer, similar to many dump truck applications." A trailer manufacturer has asked you to confirm "that this lighting follows the requirements that the tail/brake/turn lights be mounted as far apart as practicable."
It is apparent from your letter, product brochure, and photo that the specific purpose of the trailer is to carry the forklift, and, therefore, that the forklift is part of the trailer's normal equipment. Under S184.108.40.206 of Standard No. 108, when motor vehicle equipment prevents compliance with the visibility or photometric requirements of the standard by any required lamp or reflective device, an auxiliary lamp or device may be provided to meet these requirements. We note that the forklift is equipped with conspicuity marking which will be visible from the side of the trailer when it is carried on the trailer, as well as well as a red rear side reflector. There appear to be additional lamps and reflectors on the rear of the forklift, although this is not clearly indicated. We believe that compliance of the vehicle with Standard No. 108 for certification purposes must be determined
with the forklift installed (the photo you enclosed appears to depict the trailer without the forklift). However, because the trailer can be used without the forklift, care should be taken to ensure that the trailer carries the full complement of trailer lighting and marking equipment specified in Standard No. 108 when the forklift is removed.
You are correct that Standard No. 108 requires taillamps, stop lamps and turn signal lamps to be mounted "as far apart as practicable". The word "practicable" was chosen by NHTSA in order to afford manufacturers maximum flexibility in designing their products for specific end needs. When a manufacturer has determined that these lamps, on any specific vehicle, are "as far apart as practicable" with respect to that vehicle, then the manufacturer may certify compliance with all applicable Federal motor vehicle safety standards including Standard No. 108. NHTSA will not contest that certification unless it is clearly erroneous. NHTSA recognizes that required lamps mounted on the rear of a narrow forklift which is part of a trailer's rear lighting equipment may be mounted closer to the vehicle's vertical centerline than would be the case with trailers of a more conventional configuration, and that it might not be practicable to locate them at a wider distance from the centerline.
If you have any further questions, you may refer them to Taylor Vinson of this Office (phone: 202-366-5263).
Samuel J. Dubbin Chief Counsel ref:108 d:4/24/96