Back to Search
Start Over
Leakage in air handling units, the effects on the transmission of airborne infections.
- Source :
- Building & Environment; Apr2023, Vol. 233, pN.PAG-N.PAG, 1p
- Publication Year :
- 2023
-
Abstract
- The possibility of unfavorable leakages, especially with infectious diseases, in heat recovery systems in air handling units (AHU) is an essential issue. Typical configurations of AHU are analyzed in this aspect, based on their pressure distribution. It is shown that analyzing only for the design conditions is insufficient and that the changing pressure drops of the air filters due to their nonuniform soiling should be taken into account. The novelty of this paper is in proposed method of considering these leaks in the Wells-Riley model, widely used in the literature for airborne transmission of infectious diseases, including the leakage correction factor f h r l e a k (outdoor fresh air correction factor) based on EATR (exhaust air transfer ratio). Using the proposed method, for typical rooms, on the example of the SARS-CoV-2 virus and its Delta and Omicron variants, it is shown that considering leaks in heat recovery systems in AHU increases the probability of pathogen transmission. The highest increase in the absolute value of the probability of infection is observed in the single office scenario (4.1%) and in the auditorium with a sick speaker scenario (2.7%). The highest increase in reproduction number is observed in the auditorium with a sick speaker scenario (2.69). Such significant changes in reproduction number, including its change from R < 1.0 to R > 1.0 (auditorium with sick speaker for Delta variant of the virus), are crucial from the point of view of considering event scenarios; they slow down or accelerate the pandemic. [Display omitted] • Leakages in the heat recovery system of the AHU depend on the fan configuration. • Changes in AHU filters pressure drops due to soiling should be considered. • The most unfavorable configurations of air handling units were indicated. • The leakage correction factor for the Wells-Riley model is proposed. • Leakages increase the calculated probability of transmission of airborne infection. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 03601323
- Volume :
- 233
- Database :
- Supplemental Index
- Journal :
- Building & Environment
- Publication Type :
- Academic Journal
- Accession number :
- 162240977
- Full Text :
- https://doi.org/10.1016/j.buildenv.2023.110074