Determination of upstream aerosol concentration in leak detection of high efficiency particulate air filter in biosafety cabinet
Objective To investigate the appropriate upstream aerosol concentration in the integrity test of the high efficiency particulate air(HEPA)filter of the biosafety cabinet.Methods According to the method of YY 0569-20116.3.2 of Class II biological safety cabinet,different concentration of PAO aerosol ranged from 11-91 μg/L were applied to the upwind side of the HEPA filter of a biological safety cabinet,and the leakage rates were detected downstream,and the correlation between leakage rate and upstream aerosol concentration was studied.Results When the upstream aerosol concentrations ranged from 11-50 μg/L,the leakage rates were negatively correlated with the upstream aerosol concentration,and the leakage rate of the supply air HEPA filter ranged from 0.000 1%-0.002 1%,and the leakage rate of the exhaust HEPA filter ranged from 0.000 1%-0.005 3%.At the upstream aerosol concentration＞50 μg/L,the maximum leak rate no longer changed.Conclusion The upstream aerosol concentration of 10-30 μg/L is more appropriate in the leakage detection process of HEPA filter in biological safety cabinet.
万方数据
维普
