汽化过氧化氢空间浓度衰减与消毒作用持续性的研究

Study on spatial concentration attenuation and disinfection sustainability of vaporized hydrogen peroxide

目的 观察汽化过氧化氢消毒设备消毒过程中空间过氧化氢浓度变化规律,明确程序结束后空间持续密闭时间与消毒效果的相关性,为生物安全实验室空间消毒提供正确指导。方法 用该设备的低流量程序对体积为67m^3和140m^3的两间生物安全实验室进行空间消毒,以染有嗜热脂肪杆菌芽胞的不锈钢圆片作为生物指示剂置于各地面监测点,在程序运行完毕后的不同时间点取出菌片进行活菌计数,计算杀灭对数值,并全程监测空间过氧化氢浓度。结果 低流量程序结束后0h,67m^3和140m^3两间实验室地面的菌片均未被完全杀灭,结束后2h,仅140m^3实验室地面的菌片未被完全杀灭。结束后5h,两间实验室地面各处菌片均被完全杀灭。汽化过氧化氢自然衰减缓慢,需要数小时才能达到人体安全水平。结论 汽化过氧化氢消毒设备杀菌效果与实验室空间大小呈负相关。消毒程序结束后空间残留过氧化氢的持续杀菌作用与密闭时间呈正相关,即延长实验室密闭时间可提高空间消毒效果,同时避免实验人员暴露于超安全限值过氧化氢环境。

Objective To observe the variation of concentration of hydrogen peroxide in space during the sterilization of vaporized hydrogen peroxide system,find the correlation between sealing time and disinfection effect,provide effective guidance for space disinfection of biosafety laboratory. Methods Space disinfection of two different size biosafety laboratories with 67 and 140 cubic meters under low-flow programs,the bacillus stearothermophilus were placed at various ground monitoring sites as the biological indicator,which taken out to calculate the kill logarithms value at different time,and the concentration of vaporized hydrogen peroxide was monitored during the whole process. Results At end of the low-flow program,the indicators in both laboratories were not completely killed.The indicators in 140 cubic meters laboratory were not completely killed after 2 h.The indicators in both laboratories were completely killed after 5 h.The concentration of hydrogen peroxide vapor need take several hours to reach the safety level. Conclusion The disinfection effect of vaporized hydrogen peroxide is negatively correlated with the size of laboratory space.The continuous disinfection effect of hydrogen peroxide vapor remaining in space after the end of program was positively correlated with the sealing time.That is,extending the sealed time of laboratory can improve the disinfection effect and avoid exposure to high concentrations of vaporized hydrogen peroxide environment.