Research and application of differential pressure control technologies during working condition transformation process in high-level biosafety laboratories

This paper presents the concept of working condition transformation, the principles of differential pressure control, the determination of the boundary of the protective area, and the airtightness design of the enclosure structure in high-level biosafety laboratories. The key technologies of differential pressure control for working condition transformation from the aspects of supply and exhaust fans, airtight valves, constant/variable air volume valve design, and system control strategies are presented. Its application reliability is validated with a case study of a 4.4.3 class animal biosafety level 3 (ABSL-3) laboratory.