Survey of air exchange rates and evaluation of airborne infection risk of COVID-19 on commuter trains.

Publisher: Elsevier Science Country of Publication: Netherlands NLM ID: 7807270 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1873-6750 (Electronic) Linking ISSN: 01604120 NLM ISO Abbreviation: Environ Int Subsets: MEDLINE

Publication: : Amsterdam : Elsevier Science
Original Publication: Oxford; Elmsford, N. Y., Pergamon Press.

Air Microbiology* ; Air Pollution, Indoor* ; COVID-19*/transmission ; Railroads* ; Ventilation*; Air Conditioning ; Humans ; SARS-CoV-2

To identify potential countermeasures for coronavirus disease (COVID-19), we determined the air exchange rates in stationary and moving train cars under various conditions in July, August, and December 2020 in Japan. When the doors were closed, the air exchange rates in both stationary and moving trains increased with increasing area of window-opening (0.23-0.78/h at 0 m ² , windows closed to 2.1-10/h at 2.86 m ² , fully open). The air exchange rates were one order of magnitude higher when doors were open than when closed. With doors closed, the air exchange rates were higher when the centralized air conditioning (AC) and crossflow fan systems (fan) were on than when off. The air exchange rates in moving trains increased as train speed increased, from 10/h at 20 km/h to 42/h at 57 km/h. Air exchange rates did not differ significantly between empty cars and those filled with 230 mannequins representing commuters. The air exchange rates were lower during aboveground operation than during underground. Assuming that 30-300 passengers travel in a train car for 7-60 min and that the community infection rate is 0.0050-0.30%, we estimated that commuters' infection risk on trains was reduced by 91-94% when all 12 windows were opened (to a height of 10 cm) and the AC/fan was on compared with that when windows were closed and the AC/fan was off.
(Copyright © 2021. Published by Elsevier Ltd.)

N Engl J Med. 2020 Feb 20;382(8):727-733. (PMID: 31978945)
JAMA Intern Med. 2020 Dec 1;180(12):1665-1671. (PMID: 32870239)
Environ Health Perspect. 2021 Apr;129(4):47002. (PMID: 33793301)
Am J Epidemiol. 1978 May;107(5):421-32. (PMID: 665658)
Indoor Air. 2021 Mar;31(2):314-323. (PMID: 32979298)
Clin Infect Dis. 2020 Jul 28;71(15):841-843. (PMID: 32047895)
N Engl J Med. 2020 Apr 16;382(16):1564-1567. (PMID: 32182409)
Risk Anal. 2006 Aug;26(4):1085-96. (PMID: 16948699)
Build Simul. 2020;13(6):1321-1327. (PMID: 32837691)
J Occup Environ Hyg. 2007 Apr;4(4):253-9. (PMID: 17365496)
J Aerosol Sci. 2009 Feb;40(2):122-133. (PMID: 32287373)
J Infect Dis. 2020 Sep 1;222(7):1098-1102. (PMID: 32691828)
Toxicol Ind Health. 2020 Sep;36(9):634-643. (PMID: 33085569)
Risk Anal. 2010 Jul;30(7):1129-38. (PMID: 20497390)
Indoor Air. 2007 Jun;17(3):211-25. (PMID: 17542834)
Indoor Air. 2013 Aug;23(4):332-41. (PMID: 23336325)
Build Environ. 2021 Jun;196:107788. (PMID: 33746341)
N Engl J Med. 2020 Sep 24;383(13):1283-1286. (PMID: 32857487)
PLoS One. 2011;6(6):e21481. (PMID: 21731764)
Environ Int. 2021 Feb;147:106338. (PMID: 33401172)
Environ Sci Pollut Res Int. 2021 Aug;28(31):42204-42216. (PMID: 33797051)
Environ Int. 2020 Aug;141:105794. (PMID: 32416374)
JAMA. 2021 Apr 13;325(14):1464-1465. (PMID: 33616617)
Nature. 2020 May;581(7809):465-469. (PMID: 32235945)
Microb Risk Anal. 2021 Dec;19:100162. (PMID: 33778137)
J Occup Environ Med. 2015 May;57(5):501-8. (PMID: 25816216)
Environ Int. 2020 Nov;144:106039. (PMID: 32822927)
Risk Anal. 2009 Sep;29(9):1292-303. (PMID: 19558389)
Indoor Air. 2010 Feb;20(1):2-16. (PMID: 19874402)
Am J Epidemiol. 1983 Oct;118(4):573-82. (PMID: 6637984)
Lancet Infect Dis. 2020 May;20(5):565-574. (PMID: 32213337)
J Clin Virol. 2020 Jun;127:104384. (PMID: 32361285)
Nature. 2020 Sep;585(7824):268-272. (PMID: 32396922)

Keywords: Airflow velocity; Commuter; Droplet nuclei; SARS-CoV-2; Transmission; Ventilation

Date Created: 20210731 Date Completed: 20211006 Latest Revision: 20240402

20240402

PMC8299185

10.1016/j.envint.2021.106774

34332303