Cargando…

Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom

Many indoor places, including aged classrooms and offices, prisons, homeless shelters, etc., are poorly ventilated but resource-limited to afford expensive ventilation upgrades or commercial air purification systems, raising concerns on the safety of opening activities in these places in the era of...

Descripción completa

Detalles Bibliográficos
Autores principales: He, Ruichen, Liu, Wanjiao, Elson, John, Vogt, Rainer, Maranville, Clay, Hong, Jiarong
Formato: Online Artículo Texto
Lenguaje:English
Publicado: AIP Publishing LLC 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8142835/
https://www.ncbi.nlm.nih.gov/pubmed/34040337
http://dx.doi.org/10.1063/5.0050058
_version_ 1783696631230627840
author He, Ruichen
Liu, Wanjiao
Elson, John
Vogt, Rainer
Maranville, Clay
Hong, Jiarong
author_facet He, Ruichen
Liu, Wanjiao
Elson, John
Vogt, Rainer
Maranville, Clay
Hong, Jiarong
author_sort He, Ruichen
collection PubMed
description Many indoor places, including aged classrooms and offices, prisons, homeless shelters, etc., are poorly ventilated but resource-limited to afford expensive ventilation upgrades or commercial air purification systems, raising concerns on the safety of opening activities in these places in the era of the COVID-19 pandemic. To address this challenge, using computational fluid dynamics, we conducted a systematic investigation of airborne transmission in a classroom equipped with a single horizontal unit ventilator (HUV) and evaluate the performance of a low-cost box fan air cleaner for risk mitigation. Our study shows that placing box fan air cleaners in the classroom results in a substantial reduction of airborne transmission risk across the entire space. The air cleaner can achieve optimal performance when placed near the asymptomatic patient. However, without knowing the location of the patient, the performance of the cleaner is optimal near the HUV with the air flowing downwards. In addition, we find that it is more efficient in reducing aerosol concentration and spread in the classroom by adding air cleaners in comparison with raising the flow rate of HUV alone. The number and placement of air cleaners need to be adjusted to maintain their efficacy for larger classrooms and to account for the thermal gradient associated with a human thermal plume and hot ventilation air during cold seasons. Overall, our study shows that box fan air cleaners can serve as an effective low-cost alternative for mitigating airborne transmission risks in poorly ventilated spaces.
format Online
Article
Text
id pubmed-8142835
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher AIP Publishing LLC
record_format MEDLINE/PubMed
spelling pubmed-81428352021-05-24 Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom He, Ruichen Liu, Wanjiao Elson, John Vogt, Rainer Maranville, Clay Hong, Jiarong Phys Fluids (1994) Articles Many indoor places, including aged classrooms and offices, prisons, homeless shelters, etc., are poorly ventilated but resource-limited to afford expensive ventilation upgrades or commercial air purification systems, raising concerns on the safety of opening activities in these places in the era of the COVID-19 pandemic. To address this challenge, using computational fluid dynamics, we conducted a systematic investigation of airborne transmission in a classroom equipped with a single horizontal unit ventilator (HUV) and evaluate the performance of a low-cost box fan air cleaner for risk mitigation. Our study shows that placing box fan air cleaners in the classroom results in a substantial reduction of airborne transmission risk across the entire space. The air cleaner can achieve optimal performance when placed near the asymptomatic patient. However, without knowing the location of the patient, the performance of the cleaner is optimal near the HUV with the air flowing downwards. In addition, we find that it is more efficient in reducing aerosol concentration and spread in the classroom by adding air cleaners in comparison with raising the flow rate of HUV alone. The number and placement of air cleaners need to be adjusted to maintain their efficacy for larger classrooms and to account for the thermal gradient associated with a human thermal plume and hot ventilation air during cold seasons. Overall, our study shows that box fan air cleaners can serve as an effective low-cost alternative for mitigating airborne transmission risks in poorly ventilated spaces. AIP Publishing LLC 2021-05 2021-05-11 /pmc/articles/PMC8142835/ /pubmed/34040337 http://dx.doi.org/10.1063/5.0050058 Text en © 2021 Author(s) Published under license by AIP Publishing. 1070-6631/2021/33(5)/057107/14/$30.00 https://creativecommons.org/licenses/by/4.0/All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) ).
spellingShingle Articles
He, Ruichen
Liu, Wanjiao
Elson, John
Vogt, Rainer
Maranville, Clay
Hong, Jiarong
Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom
title Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom
title_full Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom
title_fullStr Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom
title_full_unstemmed Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom
title_short Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom
title_sort airborne transmission of covid-19 and mitigation using box fan air cleaners in a poorly ventilated classroom
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8142835/
https://www.ncbi.nlm.nih.gov/pubmed/34040337
http://dx.doi.org/10.1063/5.0050058
work_keys_str_mv AT heruichen airbornetransmissionofcovid19andmitigationusingboxfanaircleanersinapoorlyventilatedclassroom
AT liuwanjiao airbornetransmissionofcovid19andmitigationusingboxfanaircleanersinapoorlyventilatedclassroom
AT elsonjohn airbornetransmissionofcovid19andmitigationusingboxfanaircleanersinapoorlyventilatedclassroom
AT vogtrainer airbornetransmissionofcovid19andmitigationusingboxfanaircleanersinapoorlyventilatedclassroom
AT maranvilleclay airbornetransmissionofcovid19andmitigationusingboxfanaircleanersinapoorlyventilatedclassroom
AT hongjiarong airbornetransmissionofcovid19andmitigationusingboxfanaircleanersinapoorlyventilatedclassroom