Assessment of the risk of infectious aerosols leaking to the environment from BSL-3 laboratory HEPA air filtration systems using model bacterial aerosols--颗粒学报PARTICUOLOGY

Wen, Z., Yang, W., Li, N., Wang, J., Hu, L., Li, J., Yin, Z., Zhang, K., & Dong, X. (2014). Assessment of the risk of infectious aerosols leaking to the environment from BSL-3 laboratory HEPA air filtration systems using model bacterial aerosols. Particuology, 13, 82–87. https://doi.org/10.1016/j.partic.2012.11.009

Zhanbo Wen, Wenhui Yang, Na Li, Jie Wang, Lingfei Hu, Jinsong Li^*, Zhe Yin, Ke Zhang, Xiaokai Dong

State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China

10.1016/j.partic.2012.11.009

Volume 13, April 2014, Pages 82-87

Received 12 July 2012, Revised 14 September 2012, Accepted 21 November 2012, Available online 15 June 2013.

E-mail: lij-s@163.com

Highlights

• Filtration efficiency of HEPA filter air purification system of BSL-3 lab was assessed.

• The purification system was found effective against bacterial aerosol leakage.

• The aerosol test method adopted was capable of evaluating HEPA filter air purification system.

Abstract

To assess the risk of infectious bacterial aerosols leaking to the environment, the filtration efficiency of a biosafety level 3 (BSL-3) laboratory high-efficiency particulate (HEPA) filter was investigated using the aerosolized bacteria Serratia marcescens. The aerosol size was measured using an Andersen sampler. Eight first stage HEPA filters (numbered 1–8) were distributed in contaminated labs and exhausts from each of the first stage HEPA filters were aggregated and filtered through one second stage HEPA filter before being released to the environment. In total, 8 first-stage and 1 second-stage HEPA filters from the BSL-3 air purification system were analyzed. No S. marcescens was detected in first stage filters 1, 2, 4, 5, 7 and 8 and the second stage HEPA filter. The filtration efficiencies against aerosolized S. marcescens were >99.9999%. First stage filter numbers 3 and 6 had filtration efficiencies of 99.9825% and 99.9906%, respectively. When filter number 3 was replaced by a new filter and the bracket for filter number 6 was sealed, no aerosolized S. marcescens was detected in the filtered air. Our work suggests that the BSL-3 laboratory HEPA filter air purification system is effective against bacterial aerosols, with little to no bacterial leakage into the environment.

Graphical abstract

Keywords

Bacterial aerosol; Filtration efficiency; HEPA filters; Serratia marcescens

文章导读