25 Pa. Code § 264a.180
Weighing or measuring facilities, if necessary or when required by the Department, shall weigh hazardous wastes brought to the treatment, storage or disposal facility, except for captive facilities that handle liquids or flowable wastes-less than 20% solids-amenable to accurate flow measurements, or captive facilities that possess other waste inventory controls-volume controls. Weighing facilities shall be capable of weighing the maximum anticipated load plus the weight of the transport vehicle. The precision of weighing devices shall be certified by the Department of Agriculture. For offsite facilities or onsite facilities receiving waste from offsite sources, the hours of operation for the facility shall be prominently displayed on a sign at the entrance. The lettering shall be a minimum of 4 inches in height and of a color contrasting with its background.
25 Pa. Code § 264a.180