Pressure control methods in high-level biosafety laboratories

Summarizes the pressure control methods used in 17 high-level biosafety laboratories with air tightness requirements, including BSL-4 and BSL-3-Ag, which are established, under construction or under design. Presents air control models and their characteristics of variable air supply and constant air exhaust, constant air supply and variable air exhaust, and constant air supply and exhaust (large pressure difference). Discusses the influence of different types of valves, connection mode of ⅡB2 biosafety cabinets, air volume calculation, exhaust fan selection and the mode of indoor air supply and exhaust on the pressure control system. Discusses the development direction of stability, accuracy and intelligence of pressure control. Presents the suggestions and comments for the revision of relevant standards in the future.