To address the shortage and corresponding reuse of disposable masks and respirators caused by the COVID-19 outbreak, this study independently built a mask/respirator simulation test system based on stringent standards. Through substituting naked virus strain with 0~200 nm NaCl aerosols, two masks and three N95 respirators commonly used during the epidemic were tested under simulated human breathing flows of 15, 50 and 85 L/min. The results show that during the 8-h testing process, the penetration value of each tested mask or respirator increases linearly and the inspiratory resistance rises slowly; after 8 h, the filtration efficiency of each N95 respirator is still over 95%, and the inspiratory resistance is below 300 Pa. Subsequently, different disinfection measures were applied, and it was found that hot-water soaking, alcohol spraying and high-pressure steaming greatly reduce the filtration efficiency, while ultraviolet irradiation and dry heating barely influence the filtration efficiency and inspiratory resistance, which can still guarantee the protection level of the respirators for reuse. This work can serve as a reference for the disinfection and reuse of disposable masks and respirators during the early stage of the epidemic outbreak.
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