Washington Revised Code Title 81. Transportation § 81.61.020. Minimum standards for safe maintenance and operation of passenger-carrying vehicles--Rules and orders--Scope

(1) The construction and mechanical equipment of the passenger-carrying vehicles, including lighting devices and reflectors, exhaust system, rear vision mirrors, service and parking brakes, steering mechanisms, tires, warning and signaling devices, windshield wipers, and heating equipment capable of maintaining a reasonable temperature in passenger areas;

(2) The operation of passenger-carrying vehicles, including driving rules, the loading and carrying of passengers, maximum daily hours of service by drivers, minimum age and skill of drivers, physical condition of drivers, refueling, road warning devices, and the transportation of gasoline and explosives;

(3) The safety of passengers in a passenger-carrying vehicle, including emergency exits, fire extinguishers, first aid kits, facilities for communication between cab and rear compartments, means of ingress and egress, side walls, canopy, tail gates, or other means of retaining passengers within the passenger-carrying vehicle.