FILTRATION EFFICIENCY STUDY OF GLASS-FIBER FILTER MEDIA FOR AIRBORNE BACTERIA BIOAEROSOL

摘要

Ventilation air filters are the most commonly means to effectively filter the biological particles. In order to evaluate the performances of bioaerosol filtration devices and media, the choice of performance test methods and characteristic bioaerosol markers are most important factors. We studied the filter media performance with the commonly used Escherichia coli and Serratia marcescens as airborne bio-particle challenges. We used seven different kinds of filter media to measure their particle counting filtration efficiencies in the same standard filtration velocity. And we also used the Kowalski and William model to calculate the theoretical efficiencies of the two. The results show that the efficiency of S. marcescens has a better match with the theoretical result than E.coli. As on the ordinary agar culture, S. marcescens colonies appear bright red, which makes it easier to be detected with less counting error. We suggest taking S. marcescens as characteristic bioaerosol as the maker of bacteria in filtration performance evaluation.