No weighmaster shall weigh a vehicle or combination of vehicles to determine the weight of such vehicle or combination of vehicles unless the weighing device has a platform of sufficient size to accommodate such vehicle or combination of vehicles fully and completely as one entire unit. When a combination of vehicles must be broken up into separate units in order to be weighed as prescribed, each separate unit shall be entirely disconnected before weighing and a separate certified weight ticket shall be issued for each separate unit.
RCW 15.80.580