The research, published in the journal PeerJ, found that upper room UV germicidal irradiation (UVGI) can kill SARS-CoV-2 virus particles, which can be transmitted by aerosolised droplets that float in the air.
UVC is known to be very effective at ‘killing’, or inactivating, microorganisms however this type of UV light is harmful to humans. Upper room UVGI cleverly uses UVC light to create an irradiation field above the heads of room occupants so it can disinfect the air whilst keeping people within the room safe.
The study, led by researchers from Queen Mary University of London and Leeds Beckett University, tested the feasibility of upper room UVGI to reduce Covid-19 transmission by analysing historical published data examining the effect of UV irradiation on coronaviruses. Evaluating all the data, the research team showed that SARS-CoV-2 virus particles found in the air are likely to be susceptible to UVC, and also that the levels of UVC light required to inactivate the virus would be practical and safe for upper room applications.
Minimizing the risk
It is now becoming widely accepted that transmission of SARS-CoV-2 virus particles through tiny respiratory droplets, is one of the main ways Covid-19 spreads between people. The risk of airborne transmission is especially high in poorly ventilated buildings and there is an urgent need for technologies to reduce the spread of Covid-19 within these spaces.
The research team are now focusing their efforts on understanding how UV air disinfection technologies could be put into practice.
One project they’re currently working on will investigate the use of a low-cost air purifier system to ‘disinfect’ air based on the UVC technology. “The idea is that air could be taken out of the room using an air purifier and disinfected with UVC light, before the ‘clean’ air is then put back into the room,” said Dr Avital.
Publication: 'Upper-room ultraviolet air disinfection might help to reduce COVID-19 transmission in buildings: a feasibility study' Beggs CB, Avital EJ (2020) PeerJ 8:e10196 https://doi.org/10.7717/peerj.10196.