Each pot or compartment of each vehicle shall be labeled to indicate the certified gallonage capacity, based on a volumetric gallon equaling 231 cubic inches of liquid, on each side of the pot or compartment in a place and manner that shall be readily discernible at a distance of 50 feet when the vehicle is not in motion. The gallonage capacity of each pot or compartment need not be labeled if the vehicle bears an identification plate affixed by the manufacturer indicating the certified gallonage capacity by pot or compartment.
Md. Code Regs. 03.03.03.06