This RP provides a uniform method for calculating the location of the minimum vertical ground clearance for rigid auxiliary equipment – such as fuel tanks, storage boxes, side-door steps, tire carriers, lift gates – that may be affixed underneath the semi-trailer without contacting the ground when the trailer goes over a change in grade, including grade changes attributable to loading docks, railroad crossings, steep driveways, and the like. This RP assumes that the auxiliary devices will not adversely interact or interfere with the normal workings of the trailer. Even though a generic van trailer is depicted, the same method may be adapted to other semi-trailers.

October 2024 Edition.