Ventilation Design of Cleanrooms
During the production process of various electronic products, it is inevitable to discharge various dusts, harmful gases, and hazardous substances. An effective way to prevent their diffusion and pollution in the cleanroom is to adopt local exhaust at relevant equipment and discharge them outdoors after treatment to meet the standards. Local exhaust systems should be set up independently under the following circumstances: ① When the exhaust media can produce enhanced corrosiveness, toxicity, or combustion and explosion hazards after mixing. ② When there is a significant difference between toxic and non - toxic substances in the exhaust media, with a large difference in toxicity. ③ For flammable and explosive exhaust and general exhaust.
When designing the exhaust system of a cleanroom, the following technical measures should be taken: To prevent outdoor air from flowing back into the room, causing pollution and dust accumulation, common anti - backflow measures include: ⑴ Installing medium - efficiency filters. ⑵ Using check valves, which are convenient to use but have poor sealing performance. ⑶ Using airtight valves, which have good sealing performance but complex structures. ⑷ Using automatic control devices, etc. ① Local exhaust systems containing flammable and explosive substances should adopt fire - prevention and explosion - prevention measures suitable for the discharged substances. ② When the harmful concentration and emission amount of the exhaust media exceed the national or local regulations on harmful substance emission concentration and emission amount, they should be treated harmlessly and can only be discharged into the atmosphere after meeting the standards. ③ For exhaust systems containing water vapor and condensable substances, a slope and a discharge port should be set up to promptly discharge the condensate. Production - assisting rooms in clean workshops, such as shoe - changing rooms, outer - clothing storage rooms, washing rooms, toilets, and bathing rooms, should be equipped with ventilation measures. The static pressure value in these rooms should be lower than that in the clean area. Cleanrooms should be equipped with an emergency exhaust system according to the requirements of the production process. The emergency exhaust system should be equipped with automatic and manual control switches. The manual control switches should be installed at easily operable locations inside and outside the cleanroom respectively. Generally, cleanrooms (zones) where harmful gases or flammable and explosive gases may be emitted should be equipped with emergency exhaust devices. The manufacturing materials, insulation materials, and coatings of the equipment, pipelines, and accessories in the exhaust system should be selected appropriately according to the nature and state of the discharged gases.
Usually, the following requirements should be met: ① The air ducts of the exhaust system should be made of non - combustible materials. The non - combustible materials referred to here are various types of metal sheets, including carbon steel, stainless steel, and non - ferrous metal sheets. The selection should be determined according to the nature of the exhaust gas. ② Air ducts for discharging corrosive gases should be made of corrosion - resistant and flame - retardant materials. The flame - retardant materials referred to here are mainly glass - fiber - reinforced plastics with an oxygen index of 32 or higher. ③ Accessories, insulation materials, sound - absorbing materials, and coatings should all be made of non - combustible or flame - retardant materials. The non - combustible materials referred to here are mainly rock wool, glass wool, etc.; the flame - retardant materials are mainly (rubber - plastic sponge) and polyurethane with an oxygen index of 32 or higher.
Suzhou Pharma Machinery Co.,Ltd.
2025/09/29
Gino
