医用防护口罩防护效率及佩戴时间的研究

The study on the filter efficiency and wearing time of medical protective mask

目的测试使用前的N95医用防护口罩(简称"N95口罩")、外科口罩和纱布口罩及N95口罩在佩戴不同时间的过滤效率和呼吸阻力变化,为呼吸道传染病领域的呼吸防护提供指导。方法选用某公司生产的D32-N95型医用防护口罩52只、普通外科口罩50只、12层纱布口罩42只及24层纱布口罩51只。采用美国TSI公司生产的测试仪器TSI-8130测量过滤效率和呼吸阻力,测试方法与NIOSH N95和国家标准GB 19083-2010测试方法一致。分别测量N95口罩、外科口罩和纱布口罩的过滤效率和呼吸阻力。同时分别佩戴N95口罩0.5、1、2d直至7和14d(以工作时间4h为0.5d),佩戴后1h内测量其过滤效率和呼吸阻力。结果N95口罩的平均过滤效率为97.4%,12层纱布口罩为32.3%,24层纱布口罩为43.9%,外科口罩为18.4%,差异有统计学意义(F=4511.5,P<0.05)。N95口罩使用2d过滤效率仍在95%以上,6d在90%以上,14d在80%以上。根据数学模型,使用45d时仍可高于24层纱布口罩的过滤效率43.9%。呼吸阻力变化不大,各类口罩佩戴14d都在14mm H2O(1mm H2O=0.0098kPa)以下,低于国家标准要求的35mm H2O。结论N95口罩的过滤效率大大高于纱布口罩和外科口罩,且可以较长时间使用,可用于呼吸道疾病领域内的感染控制。

Objective To test the filter efficiency and respiratory resistance of N95 medical mask,surgical masks and gauze masks（12-layer and 24-layer）before wear,test the filter efficiency and respiratory resistance change of N95 masks with different wearing time,and to provide a guidance for respiratory protection of respiratory infectious diseases.Methods Filtration efficiencies and respiratory resistances of 52 D32-N95 medical masks,50 general surgical masks,42 12-layer gauze masks and 51 24-layer gauze masks,which were all produced by a science and technology development company were tested before wear by TSI-8130 produced by TSI Company of United States,the test method was the same as that used by NIOSH-N95 and National standard GB 19083-2010.N95 masks were worn half day,1 day,2 days until 7 days and 14 days（Taking four hours of woking time as 0.5 day） respectively,the filtration efficiency and respiratory resistance were tested within one hour after wear.Results The filter efficiency of N95 masks was 97.4%,32.3% for 12-layer gauze masks,43.9% for 24-layer masks and 18.4% for surgical masks,the differences were statistically significant（F=4511.5,P0.05）.N95 masks＇ filtration efficiency were still more than 95% after wearing two days,more than 90% on the sixth day and more than 80% on the fourteenth day.According to the mathematical model,the filter efficiency of N95 masks was still higher than that of 24-layer of gauze masks（43.9%） after wearing 45 days.The respiratory resistances of different masks changed little and were less than 14 mmH2O（1 mmH2O=0.0098 kPa） on the fourteen day,which were lower than the national standard of 35 mmH2O.Conclusion The filter efficiency of N95 mask is much higher than those of gauze masks and surgical masks,it can be used for longer time,and can be used in the field of respiratory disease control.