Testing mobile air purifiers in a school classroom: reducing the airborne transmission risk for SARS-CoV-2
- Airborne transmission of SARS-CoV-2 through virus-containing aerosol particles has been established as an important pathway for Covid-19 infection. Suitable measures to prevent such infections are imperative, especially in situations when a high number of persons convene in closed rooms. Here we tested the efficiency and practicability of operating four air purifiers equipped with HEPA filters in a high school classroom while regular classes were taking place. We monitored the aerosol number concentration for particles > 3 nm at two locations in the room, the aerosol size distribution in the range from 10 nm to 10 µm, PM10 and CO2 concentration. For comparison, we performed similar measurements in a neighboring classroom without purifiers. In times when classes were conducted with windows and door closed, the aerosol concentration was reduced by more than 90 % within less than 30 minutes when running the purifiers (air exchange rate 5.5 h-1). The reduction was homogeneous throughout the room and for all particle sizes. The measurements are supplemented by a calculation estimating the maximum concentration levels of virus-containing aerosol from a highly contagious person speaking in a closed room with and without air purifiers. Measurements and calculation demonstrate that air purifiers potentially represent a well-suited measure to reduce the risks of airborne transmission of SARS-CoV-2 substantially. Staying for two hours in a closed room with a highly infective person, we estimate that the inhaled dose is reduced by a factor of six when using air purifiers with a total air exchange rate of 5.7 h-1.
Author: | Joachim CurtiusORCiD, Manuel GranzinORCiD, Jann Erik SchrodORCiDGND |
---|---|
URN: | urn:nbn:de:hebis:30:3-735819 |
DOI: | https://doi.org/10.1101/2020.10.02.20205633 |
Parent Title (English): | medRxiv |
Document Type: | Preprint |
Language: | English |
Date of Publication (online): | 2020/12/24 |
Date of first Publication: | 2020/12/24 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2023/07/05 |
Issue: | 2020.10.02.20205633 |
Page Number: | 42 |
HeBIS-PPN: | 510536824 |
Institutes: | Geowissenschaften / Geographie / Geowissenschaften |
Dewey Decimal Classification: | 6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit |
Sammlungen: | Universitätspublikationen |
Licence (German): | ![]() |