Diameter of grab bars should be 1-1/4" to 1-1/2" (32-38mm) with 1-1/2" (38mm) clearance from the wall, and should not rotate in their fittings. Required mounting height is universally 33" to 36" (840-915mm) from the centerline of the grab bar to the finish floor. Structural strength of all grab bars and their mounting devices should withstand more than 250 pounds of force (1112 N). For all barrier-free toilet compartments, individual toilet rooms and guest bathrooms, it is recommended that a 36" (915mm) min. horizontal grab bar be installed on the back wall over the toilet and a 42" (1065mm) min. horizontal grab bar be installed on the side wall or partition nearest the toilet. This can also be accomplished with a single horizontal two-wall grab bar.