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. 2012 Mar 3;19(3):645–650. doi: 10.1007/s11771-012-1051-0

Characteristics of physical blocking on co-occupant’s exposure to respiratory droplet residuals

Xiao-ping Li 1,✉, Jian-lei Niu 1, Nai-ping Gao 2
PMCID: PMC7111536  PMID: 32288947

Abstract

Existed evidences show that airborne transmission of human respiratory droplets may be related with the spread of some infectious disease, such as severe acute respiratory syndrome (SARS) and H1N1 pandemic. Non-pharmaceutical approaches, including ventilation system and personal protection, are believed to have certain positive effects on the reduction of co-occupant’s inhalation. This work then aims to numerically study the performances of mouth covering on co-occupant’s exposure under mixing ventilation (MV), under-floor air distribution (UFAD) and displacement ventilation (DV) system, using drift-flux model. Desk partition, as one generally employed arrangement in plan office, is also investigated under MV. The dispersion of 1, 5 and 10 μm droplet residuals are numerically calculated and CO2 is used to represent tracer gas. The results show that using mouth covering by the infected person can reduce the co-occupant’s inhalation greatly by interrupting direct spread of the expelled droplets, and best performance can be achieved under DV since the coughed air is mainly confined in the microenvironment of the infected person. The researches under MV show that the two interventions, mouth covering and desk partition, achieve almost the same inhalation for fine droplets while the inhalation of the co-occupant is lower when using mouth covering for large droplets.

Key words: mouth covering, desk partition, respiratory droplets, exposure, ventilation method

References

  • [1].World Health Organization. Pandemic influenza preparedness and response: a WHO guidance document [R] Geneva: WHO; 2009. [PubMed] [Google Scholar]
  • [2].Jefferson T., Del Mar C., Dooley L., Ferroni E., Al-Ansary L. A., Bawazeer G. A., Driel M. L., Foxlee R., Rivetti A. Physical interventions to interrupt or reduce the spread of respiratory viruses: systematic review [J] BMJ. 2008;336(7635):77–80. doi: 10.1136/bmj.39393.510347.BE. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • [3].Li Y., Leung G. M., Tang J. W., Yang X., Chao C. Y. H., Lin J. Z., Lu J. W., Nielsen P. V., Niu J., Qian H., Sleigh A. C., Su H. J. J., Sundell J., Wong T. W., Yuen P. L. Role of ventilation in airborne transmission of infectious agents in the built environment-a multidisciplinary systematic review [J] Indoor Air. 2007;17(1):2–18. doi: 10.1111/j.1600-0668.2006.00445.x. [DOI] [PubMed] [Google Scholar]
  • [4].Gao N.-p., Niu J.-lei. Transient CFD simulation of the respiration process and inter-person exposure assessment [J] Building and Environment. 2006;41(9):1214–1222. doi: 10.1016/j.buildenv.2005.05.014. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • [5].Gao N.-p., Niu J.-l., Morawska Lidia. Distribution of respiratory droplets in enclosed environment under different air distribution methods [J] Building Simulation. 2008;1(4):326–335. doi: 10.1007/s12273-008-8328-0. [DOI] [Google Scholar]
  • [6].Mui K. W., Wong L. T., Wu C. L., Lai A. C. K. Numerical modeling of exhaled droplet nuclei dispersion and mixing in indoor environments [J] Journal of Hazardous Material. 2009;167(1/2/3):736–744. doi: 10.1016/j.jhazmat.2009.01.041. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • [7].Wan M. P., Chao C. Y. H. Transport characteristics of expiratory droplets and droplet nuclei in indoor environments with different ventilation airflow patterns [J] Journal of biomechanical engineering. 2007;129(3):341–353. doi: 10.1115/1.2720911. [DOI] [PubMed] [Google Scholar]
  • [8].Knight Jonathan. Researchers get to grips with cause of pneumonia epidemic [J] Nature. 2003;422(6932):547–548. doi: 10.1038/422547a. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • [9].Derrick J. L., Gomersall C. D. Protecting healthcare staff from severe acute respiratory syndrome: filtration capacity of multiple surgical masks [J] Journal of Hospital Infection. 2005;59(4):365–368. doi: 10.1016/j.jhin.2004.10.013. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • [10].Tang J. W., Liebner T. J., Craven B. A., Settles G. S. A Schlieren optical study of the human cough with and without wearing masks for aerosol infection control [J] Journal of the Royal Society Interface. 2009;6(6):S727–S736. doi: 10.1098/rsif.2009.0295.focus. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • [11].CHOUDHURY D. Introduction to the renormalization group method and turbulence modeling [R]. Canonsburg Fluent Inc Technical Memorandum TM-107. 1993.
  • [12].Lai A. C. K., Nazaroff W. W. Modeling indoor particle deposition from turbulent flow onto smooth surfaces [J] Journal of Aerosol Science. 2000;31(4):463–476. doi: 10.1016/S0021-8502(99)00536-4. [DOI] [Google Scholar]
  • [13].Kobayashi N., Chen Q.-yan. Floor-supply displacement ventilation in a small office [J] Indoor and Built Environment. 2003;12(4):281–291. doi: 10.1177/1420326X03035918. [DOI] [Google Scholar]
  • [14].Zhu S.-w., Kato S., Yang J.-hoon. Study of transport characteristics of saliva droplets produced by coughing in a calm indoor environment [J] Building and Environment. 2006;41(12):1691–1702. doi: 10.1016/j.buildenv.2005.06.024. [DOI] [Google Scholar]
  • [15].Höppe P. Temperatures of expired air under varying climatic conditions [J] International Journal of Biometeor. 1981;25(2):127–132. doi: 10.1007/BF02184460. [DOI] [PubMed] [Google Scholar]
  • [16].Wells W. F. On air-borne infection. Study II. Droplets and droplet nuclei [J]. American journal of Epidemiology. 1934;20(3):611–618. [Google Scholar]
  • [17].Xie X., Li Y., Chwang A. T. Y., Ho P. L., Seto W. H. How far droplets can move in indoor environments-revisiting the Wells evaporation-falling curve [J] Indoor Air. 2007;17(3):211–225. doi: 10.1111/j.1600-0668.2007.00469.x. [DOI] [PubMed] [Google Scholar]
  • [18].Papavergos P. G., Hedley A. B. Particle deposition behavior from turbulent flows [J] Chemical Engineering Research and Design. 1984;62(3):275–295. [Google Scholar]
  • [19].Qian H., Li Y., Nielsen P. V., Hyldgaard C. E., Wong T. W., Chwang A. T. Y. Dispersion of exhaled droplets nuclei in a two-bed hospital ward with three different ventilation systems [J] Indoor Air. 2006;16(2):111–128. doi: 10.1111/j.1600-0668.2005.00407.x. [DOI] [PubMed] [Google Scholar]

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