Transmission of COVID-19 viral particles and the risk of infection among passengers in air-conditioned buses
WU Jialin1,2, WENG Wenguo1,2
1. Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China; 2. Beijing Key Laboratory of City Integrated Emergency Response Science, Tsinghua University, Beijing 100084, China
Abstract：Aerosol transmission of the corona virus disease 2019 (COVID-19) is possible. This study analyzed COVID-19 transmission in an air-conditioned bus in Hunan Province, China. A numerical model was used to predict the transport of droplets and aerosols containing the COVID-19 virus for various air conditioning modes, particle sizes, and source locations. The results were used for quantitative evaluations of the infection risks for all passengers with comparisons to the actual transmission rate. A high proportion of exhaled viral particles from COVID-19 infected people were deposited on the inner wall of the bus and the seat surface. Changing the particle sizes and the outlet locations leads to different aerosol diffusion paths. Small aerosols containing the virus can remain suspended in the air for prolonged periods of time and become widely spread, so these pose a higher risk to passengers seated far from the source. The results are used to develop suggestions for reducing the COVID-19 infection risk in air-conditioned buses.
吴家麟, 翁文国. 新冠肺炎病毒颗粒在空调大巴中的传播与乘客感染风险[J]. 清华大学学报（自然科学版）, 2021, 61(2): 89-95.
WU Jialin, WENG Wenguo. Transmission of COVID-19 viral particles and the risk of infection among passengers in air-conditioned buses. Journal of Tsinghua University(Science and Technology), 2021, 61(2): 89-95.
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2021, Vol. 61 
