Interpretation ID: aiam3893
General Manager
Fleet Maintenance Division
Office of Fleet Management
United States Postal Service
Delivery Services Department
475 L'Enfant Plaza
SW
Washington
DC 20260-7200;
Dear Mr. Humphrey: This is in reply to your letter of January 15, 1985, to Taylor Vinso 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 heigh 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 en accidents but would like to point out that the efficacy of the lamp on vehicle (sic) 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, Frank Berndt, Chief Counsel