Some technologies or methods are used to remove the pollutants accumulated on the surface of the fume exhaust pipe, the fume treatment and purification system and other components, the pollutants in the fume purifier and the fire prevention treatment of the fume exhaust system in the kitchen operation room. Objectives: Cooperate with the fire safety emergency department to test the fire safety of public places, and ensure the fire safety and environmental health of kitchen smoke exhaust system in public places. Including fume purifier, ventilator, main air duct, smoke hood surface, lampshade in smoke hood, water delivery system, fire net, smoke exhaust port, and stove surface, kitchen equipment and cleaning system engineering accessories maintenance and installation. The key point of cleaning is to thoroughly clean the interior of the parallel flue by synchronizing the exhaust nozzle with the hood. The main method adopted is that the personnel enter the flue for cleaning. For the narrow smoke outlet, manual access to the flue or because the flue itself is complex, narrow, manual can not be cleaned, but there are significant hidden dangers, SUS can use "robot" special equipment for cleaning, leaving no dead corner, dispel customer doubts and concerns, eliminate all potential fire hazards.