Liquid impinger BioSampler's performance for size-resolved viable bioaerosol particles

Experimental data showed that when sampling aerosolized Bacillus subtilis at the flow rate of 12.5 L/min, the collection efficiency of the BioSampler decreased from 82.7% (at Vcl=20 mL) to 24.8% (at Vcl=5 mL). The results from the BacLight dye and culturing performed for the samples collected by the BioSampler achieved similar conclusions. When sampling indoor air particles, the overall collection efficiencies of all viable biological particles were 95.3%, 87.7% and 65.5%, respectively, for Vcl=20 mL, 10 mL and 5 mL at the flow rate of 12.5 L/min. When Qsampl was 20 L/min, the BioSampler performed better with Vcl= 5 mL than other volumes. The results from this work suggest that the sampling flow rate plays a dominant role in the overall physical collection efficiency while the collection volume is crucial in preserving the viability of bioaerosol particles. Different from general practice, the operating parameters for the BioSampler should thus be adjusted respectively for target viral, bacterial and fungal aerosol particles.