Commercial pressure washer is a mechanical device that uses high-pressure water to clean robust surfaces and objects such as buildings, vehicles and concrete road surfaces. It consists of an electric motor or gasoline-powered engine, water pump, a frame that holds to power source, high-pressure water pump, high-pressure hose and trigger gun. Some pressure washers, in combination with a particular nozzle, allow detergent to be introduced into the water stream, assisting in the cleaning process.