The number of air changes in the clean workshop is based on the requirements set out in the "Good Manufacturing Practices". The design uses a 100,000-level clean area: the number of air changes is 10 to 20 times / hour; the level of clean area: the number of air changes is 20 ~ 30 times / hour; 100-level clean area, the number of air changes is calculated according to the wind speed, the determination of the fresh air volume determines the fresh air volume to meet the following points a. The indoor positive pressure requirement must be met. b. The air conditioning load caused by a large amount of air in the indoor room must be met. c. Must meet the requirements of the indoor staff. The air-conditioning air supply duct in the clean air supply system is designed to be installed in the ceiling with all air ducts. The main air duct is connected to the air supply branch pipe in the ceiling of the clean area, and the clean air is supplied from the air supply duct and the air outlet. The upper part of the ceiling of the clean room is sent into the room, and an electric air volume adjusting valve is arranged at the branch of the pipe to facilitate the operation of the personnel. At the same time, the insulation material is attached to the outside of the pipeline to prevent condensation on the outer wall of the air-conditioning duct. The air supply port adopts a traditional high-efficiency filter air supply port with a static pressure box, which is evenly arranged on the ceiling. The heat insulating material is also attached to the outside of the high-efficiency filter air outlet, thus effectively preventing the pipe and the air outlet surface. The phenomenon of condensation. Avoid cross-contamination of air in different sections of the clean area, while meeting the requirements of the process for air-conditioning organization that distinguishes between people and logistics. Exhaust system generals Because of the large amount of dust pollutants generated in the interior of the clean room, when designing the air conditioning and ventilation system in the clean area, different air exhaust methods are adopted for different dust pollutant rooms.