《实验室生物安全通用要求》（GB19489-2008）要求生物安全三级实验室（BSL-3） “应可以在原位对排风高效空气（HEPA）过滤器进行消毒灭菌”。BSL-3实验室核心区排风HEPA过滤器是保证实验操作过程中产生的感染性气溶胶不外泄的最后防线，为了保障环境的安全，需在原位实现HEPA过滤器的消毒。本研究设计并制作了循环消毒样机，与排风HEPA过滤器的排风箱体的消毒接口连接，利用循环气流带动甲醛蒸汽循环穿透排风HEPA过滤器，从而实现原位消毒。结果显示，室温条件下甲醛蒸汽浓度16 mg/L，相对湿度70%，持续熏蒸循环穿透运行12 h，布置于HEPA过滤器排风箱体内用于指示消毒效果的金黄色葡萄球菌、耻垢分枝杆菌、枯草芽孢杆菌及嗜热脂肪芽孢菌均被完全杀灭，本实验室从设备及方法学两方面实现了排风HEPA过滤器的原位消毒。

Laboratories—General Requirements for Biosafety（GB 19489-2008） required “Exhaust high efficiency particulate air (HEPA) filter of Biosafety Level 3 Laboratory (BSL-3) should be sterilized in situ”. Exhaust HEPA filter is an important defensive line to ensure the biosafety of BSL-3 laboratory facilities and also the main line of defense to ensure the non-leakage of infectious aerosols generated in the experimental procedure. In situ disinfection of the HEPA filter is needed in order to protect the safety of personnel. This study designed and produced a cycle disinfection prototype (with the function of formalin volatilization, gas humidification and air circulation supply). The prototype with the disinfection interface of HEPA filter’s exhaust box were connected. And then the steam cycle of formalin was driven through the HEPA filter by air circulation supply system. Thus the in situ disinfection was realized. The results showed that formalin vapor concentration at room temperature was 16 mg/L, and the relative humidity was 70%. After 12-hour continuous fumigation cycle running through, Staphylococcus aureus, Mycobacterium smegmatis, Bacillus subtilis and Bacillus stearothermophilus were completely disinfected. As a consequence, the in situ disinfection of HEPA exhaust-air filter in both equipment and methodology is achieved.