Interpretation ID: 86-6.14

DATE: 12/15/86

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: LeRoy E. Mueller

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. LeRoy E. Mueller President Wisconsin Trailer Company Inc. Richfield, WI 53076

Dear Mr. Mueller:

Don Vierimaa of Truck Trailer Manufacturers Association has asked us to reply to your letter of June 18, 1986, in which you inquired whether a proposed rear lighting system for trailers "meets the regulations governing lights and reflectors." We understand, from your conversation on October 7 with Taylor Vinson of this Office that the trailer in question is a flat bed one, intended to tip forward to facilitate the loading and unloading of cargo.

The requirements for trailer lighting for vehicles whose overall width is 80 inches or more are imposed by Federal Motor Vehicle Safety Standard No. 108. Table I lists the required equipment items, and Table II establishes the location for them. With one exception, the system depicted by your Drawing A60686 indicates that the required equipment will be furnished in accordance with Table I. The exception is the apparent failure to provide clearance lamps. These lamps, and the three-lamp identification lamp cluster are required for wide trailers. In our view, it will be necessary to mount additional lamps on the rear of your proposed trailer to provide this function. Paragraph S4.4 of Standard No. 108 prohibits the optical combination of clearance lamps and taillamps, and clearance lamps and identification lamps.

However, the location of the lamps as shown in Drawing A60686 does not appear to meet the requirements of Table II. that they be located "on the rear", or the visibility requirements discussed below. The identification lamps and reflectors are located under the platform and 19 inches from its rear edge, while the combination stop-tail-turn signal lamps are 22 inches from the rear edge of the platform. We therefore call your attention to paragraph S4.3.1.1. of Standard No. 108, and the appropriate photometric and visibility requirements of Standard No. 108 and SAE standards incorporated by reference for rear lighting equipment. In general, vehicle equipment shall not prevent photometric compliance by rear lighting devices, which shall be located so that at least two square inches of lens area are visible at angles of 45 degrees to the left, and 15 degrees to the right of the centerpoint of the lens. However, if motor vehicle equipment prevents compliance with visibility requirements, auxiliary lamps meeting the visibility requirements shall be provided.

We are mindful that the configuratIons of certain trailers are such that compliance problems may arise that are not easily solved. I enclose a recent letter to a manufacturer who had an interpretative question similar to yours, with the thought it may be of help to you.

I hope that this is responsive to your request.

Sincerely,

Erika Z. Jones Chief Counsel

Enclosure

Mr. Donald W. Vierimaa Truck Trailer Manufacturers Association 1020 Princess Street Alexandria, VA 22314

Dear Don:

I am enclosing three (3) copies of our drawing number A60686 showing the proposed light system on the rear portion of a trailer which we intend to market.

We would like to have you forward the drawings to the proper individuals in the Department of Transportation who could give us a ruling to whether or not this system meets the regulations governing lights and reflectors. The lights and reflectors are all Class A and meet all D.O.T. requirements.

Thank you for your cooperation In this matter.

Very truly yours, WISCONSIN TRAILER CO., INC.

LeRoy E. Mueller President

LEM/pb Enclosures

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