STUDY: Predicting airborne coronavirus inactivation by far-UVC in populated rooms using a high-fidelity coupled radiation-CFD model

Whilst these (e.g. PPE, social distancing) are all effective measures, their success is tied to human behavior and hence at risk from complacency…unlike these active measures, passive use of in-room far-UVC provides an invisible barrier

STUDY: Predicting airborne coronavirus inactivation by far-UVC in populated rooms using a high-fidelity coupled radiation-CFD model

Reprint from: Nature Published: 12 November 2020.

Authors: Buchan, A.G., Yang, L. & Atkinson, K.D. Predicting airborne coronavirus inactivation by far-UVC in populated rooms using a high-fidelity coupled radiation-CFD model. Sci Rep 10, 19659 (2020). https://doi.org/10.1038/s41598-020-76597-y

Abstract: There are increased risks of contracting COVID‑19 in hospitals and long‑term care facilities, particularly for vulnerable groups. In these environments aerosolised coronavirus released through breathing increases the chance of spreading the disease. To reduce aerosol transmissions, the use of low dose far‑UVC lighting to disinfect in‑room air has been proposed. Unlike typical UVC, which has been used to kill microorganisms for decades but is carcinogenic and cataractogenic, recent evidence has shown that far‑UVC is safe to use around humans. A high‑fidelity, fully‑coupled radiation transport and fluid dynamics model has been developed to quantify disinfection rates within a typical ventilated room. The model shows that disinfection rates are increased by a further 50‑85% when using far‑UVC within currently recommended exposure levels compared to the room’s ventilation alone. With these magnitudes of reduction, far‑UVC lighting could be employed to mitigate SARS‑CoV‑2 transmission before the onset of future waves, or the start of winter when risks of infection are higher. This is particularly significant in poorly‑ventilated spaces where other means of reduction are not practical, in addition social distancing can be reduced without increasing the risk.

Take-aways:

In highly ventilated rooms, the impact of UVC 222 is high…

The combination of far-UVC and high ventilation reduces the viral count most effectively, more than halving the times when using 8.0 ACH (air changes per hour) ventilation alone.

“With these magnitudes of reduction, far‐UVC lighting could be employed to mitigate SARS‐CoV‐2 transmission before the onset of future waves, or the start of winter when risks of infection are higher”

…while in poorly ventilated rooms, UVC 222 impact is even higher

Disinfection rates are increased by a further 50‐85% when using far‐UVC within currently recommended exposure levels compared to the room’s ventilation alone

“This is particularly significant in poorly‐ventilated spaces where other means of reduction are not practical, in addition social distancing can be reduced without increasing the risk.”

Click link to read the full article : https://www.nature.com/articles/s41598-020-76597-y