Extended short-range airborne transmission of respiratory infections

JOURNAL OF HAZARDOUS MATERIALS

卷:422

Article

Chen, Wenzhao¹  Qian, Hua²  Zhang, Nan³  Liu, Fan²  Liu, Li⁴  Li, Yuguo¹ 

[1] Univ Hong Kong, Dept Mech Engn, Pokfulam Rd, Hong Kong, Peoples R China

[2] Southeast Univ, Sch Energy & Environm, Nanjing, Peoples R China

[3] Beijing Univ Technol, Beijing Key Lab Green Built Environm & Energy Eff, Beijing, Peoples R China

[4] Tsinghua Univ, Sch Architecture, Beijing, Peoples R China

关键词: Airborne transmission;    Ventilation rate;    Crowding;    Indoor environment;    COVID-19;   

DOI  :  10.1016/j.jhazmat.2021.126837

来源: Elsevier

【 摘 要 】

Debate and scientific inquiries regarding airborne transmission of respiratory infections such as COVID-19 and influenza continue. Health authorities including the WHO and the US CDC have recognized the airborne transmission of COVID-19 in specific settings, although the ventilation requirements remain to be determined. In this work we consider the long-range airborne transmission as an extended short-range airborne route, which reconciles the link between short- and long-range airborne routes. The effective short-range distance is defined as the distance in short range at which long-range route has the same volumetric exposure value as that due to short-range route. Our data show that a decrease in ventilation rate or room volume per person, or an increase in the ratio of the number of infected to susceptible people reduces the effective short-range distance. In a normal breathing scenario with one out of five people infected and a room volume of 12 m3 per person to ensure an effective short-range distance of 1.5 m, a ventilation rate of 10 L/s per person is needed for a duration of 2 h. Our results suggest that effective environmental prevention strategies for respiratory infections require appropriate increases in the ventilation rate while maintaining a sufficiently low occupancy. Practical implications: Demonstration of the long-range airborne route as an extended short-range airborne route suggests the significant role played by building ventilation in respiratory infection exposure. The reconciliation of short- and long-range airborne transmission suggests that the commonly observed dominance of close-contact transmission is a probable evidence of short-range airborne transmission, following a separate earlier study that revealed the relative insignificance of large droplet transmission in comparison with the short-range airborneroute. Existing ventilation standards do not account for respiratory infection control, and this study presents a possible approach to account for infection under new ventilation standards.

【 授权许可】

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