Interpretation ID: 23847.ztv

Captain Bruce Bugg
Special Projects Coordinator
Law Enforcement Division
Georgia Department of Motor Vehicle Safety
P.O.Box 80477
Conyers, GA 30013-8047

Dear Captain Bugg:

We are replying to your letter of December 13, 2001, and to your e-mails of December 21 and December 27, 2001, to Taylor Vinson of this Office.

The primary issue that concerns you is the mounting height of retroreflective sheeting on the side of tank trailers. Paragraph S5.7.1.4.2 of Federal Motor Vehicle Safety Standard No. 108 states that the tape shall be located "as close as practicable to not less than 375 mm and not more than 1525 mm above the road surface at the stripe centerline." The latter dimension is the equivalent of 60 inches. The drawing of a tank trailer shown in Figure 30-4 of Standard No. 108 depicts the sheeting at a height above 60 inches. However, at a mounting height of 60 inches, the sheeting will be canted downwards. In the case that prompted your letter, the tape on a trailer certified to Standard No. 108 had the sheeting located at approximately 74 inches above the road surface.

We e-mailed you a copy of an interpretation of this Office, dated October 14, 1994, to Victor Larson. We advised Mr. Larson that manufacturers of conspicuity material certify its performance on a vertical plane and that therefore the material should be mounted on a vertical plane or as close to it as the trailer shape allows. If that vertical mounting area was higher than 1525 mm, we would consider that the conspicuity material had been mounted "as close as practicable" to the maximum specified mounting height. The conspicuity material that is mounted approximately 74 inches above the road surface, as shown in photos attached to your e-mail of December 21, 2001, appears appropriately located within the meaning of our interpretation to Mr. Larson.

Citing the need for clarity with the advent of the corresponding conspicuity requirements of the Federal Motor Carrier Safety Administration (49 CFR 393.13), in your e-mail of December 27, 2001, you asked two additional questions:

"1. If a cargo tank trailer does NOT have a frame or other suitable surface below the 1525 mm (60 inch) height, is it permissible for the conspicuity treatment on the side of the trailer to be mounted at a height above 1525 mm (60 inch) and still meet the practicability requirement?"

Yes. As the Larson letter indicates, if a trailer does not have a vertical mounting surface within the 375 mm (15 inch) - 1525 mm (60 inch) range, the manufacturer must locate the side conspicuity material at the height that is as close as practicable to that range while allowing the treatment to be mounted vertically.

"2. If a cargo tank DOES have a frame or other suitable surface within the 375 mm (15 inch) - 1525 mm (60 inch) range, is a trailer with the conspicuity treatment above the 1525 mm (60 inch) height in violation of the requirements of 49 CFR Sec. 571.108 S5.7?"

If a frame or other vertical mounting surface exists within the range specified in S5.7, a vehicle with its conspicuity treatment above 1525 mm would not comply with the standard.

I hope that this answers your questions.

Sincerely,

John Womack
Acting Chief Counsel

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