Interpretation ID: 1985-01.35

TYPE: INTERPRETATION-NHTSA

DATE: 02/22/85

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: John Humphrey -- Fleet Maintenance Division, U.S. Postal Service

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. John Humphrey General Manager Fleet Maintenance Division Office of Fleet Management United States Postal Service Delivery services Department 475 L'Enfant Plaza, SW Washington, D.C. 20260-7200

This is in response to your letter of January 15, 1985, to Taylor Vinson of this office asking for a waiver of the maximum height requirement so that the Postal Service may install center stop lamps on its new delivery trucks mounted from 75 to 83 inches above the road surface.

You do not need an exemption in order to install the lamp at the height you desire. First, Standard No. 108 requires the installation of a center high mounted stop lamp on passenger cars only, and not on trucks. Secondly, the 72-inch limitation on stop lamp mounting height imposed by Standard No. 108 for stop lamps applies only to the stop lamps that are mounted on either side of the vertical centerline. There is no limitation on the mounting height of the center lamp, when required on a vehicle, or prohibition against mounting it above 72 inches on a vehicle that is not required to have it.

We appreciate the interest of the Postal Service in reducing rear end accidents but would like to point out that the efficacy of the lamp on vehicle other than passenger cars is unknown. Our studies showed that the lamp was most effective at the approximate eye height of the driver in a following vehicle, and also as an alert to the driver behind who saw the highmounted light through the intervening car. Thus, the Postal Service with its lights mounted above the rear door should not expect its vehicles in service necessarily to replicate this agency's test experience.

Sincerely,

Original Signed By

Frank Berndt Chief Counsel

January 15, 1985

Mr. Taylor Vinson, Legal Counsel Room 5219 - FMVSS - 108 NHTSA - U.S. Department of Transportation 400 7th Street, S.W. Washington, D.C. 20590

Dear Mr. Vinson:

The U.S. Postal Service is in the process of testing and procuring a new Long Life Vehicle (LLV). These vehicles are light delivery trucks and will be used primarily for residential mail delivery and collection and will replace the vehicle (Jeep) presently used for this function.

In the interest of safety we have required a high center mounted brake light on these units. Since the units will be slightly larger than the current vehicle the high mounted brake light will exceed the maximum of seventy-two (72) inches from the roadway as required by Federal Motor Vehicle Safety Standards, Part 511, 108 Table IV Location of Required Equipment.

Due to the configuration of the proposed LLV the center mounted stop lamp will be between 78 and 83 inches from the roadway at curb weight. I have enclosed a photo of the three units we are currently testing, so that you might have a better understanding of the stop lamp location.

We are requesting a waiver to this requirement to permit placement of a center mounted stop lamp on these vehicles. Your assistance will be appreciated.

Sincerely,

Mr. John Humphrey General Manager Fleet Maintenance Division Office of Fleet Management