Air purifiers could help SPREAD Covid-19 in confined spaces, research claims
- Research shows that air purifiers help move Covid-19 germs in confined spaces
- Devices are installed to purify air in small spaces where people gather, such as elevators
- Scientists say air purifiers can “increase the spread of droplets” if someone were to cough
Air purifiers could help spread Covid-19 in confined spaces such as elevators, a leading study suggests.
The quality of the air in small spaces without proper ventilation usually requires an air purifier to kill viruses and bacteria – but there is currently no system that can remove the coronavirus.
Scientists from the University of Nicosia in Cyprus conducted a study to see what would happen if someone coughed in an overcrowded elevator.
Professor Dimitris Drikakis said: “Our results show that installing an air purifier can increase the spread of droplets.”
A 3D model created by scientists shows how elevator air cleaning systems can help spread Covid-19 germs released after an infected cough
The study claims that devices increase transmission speed by moving particles laden with the virus.
The air quality in small spaces would decrease quickly without proper ventilation.
That’s why most modern elevators are equipped with air cleaners to remove any floating contaminants.
The machines use ultraviolet radiation to kill viruses and bacteria, which can be harmful.
The model created an elevator that would have room for about five people, and scientists concluded, “Installing an air purifier can increase the spread of droplets.”
Scientists at the University of Nicosia say elevators should have a lower capacity to minimize the risk of Covid-19 spreading
But sucking in dirty air and blowing out clean air contributes to ‘overall circulation’, a problem that has not been considered until now.
The researchers have made a 3D model of an elevator that can accommodate five people.
Ventilation and an air purifier were added to the elevator so that the researchers could determine how these affected air circulation.
A mild cough was then simulated in space to measure the spread of virus-infected saliva droplets.
Using the same model, previous studies have found that saliva drops can travel 18 feet in five seconds when an unmasked person coughs.
The chances of catching the virus were lowest if the room had reduced ventilation, the researchers found.
Prof Drikakis added: “We quantified the effect of air circulation on the transmission of viruses in the air and showed that installing an air purifier in an elevator significantly changes air circulation, but does not eliminate airborne transmission.”
The people of the UK have had to stay at home since the government declared a national lockdown in early January.
But for those who still go to the office or live in an apartment building, taking the elevator can be part of their daily routine.
Professor Drikakis said: ‘Our results show that installing an air purifier can increase the spread of droplets.
Most modern elevators are equipped with air purifiers to remove any floating contaminants. Images from the study show how particles move through the ‘elevator’ and may come into contact with people on board
The more people on the elevator are infected with COVID-19, the more damage an air purifier causes, the researchers also found
“The air inlet integrated into the air cleaning equipment provides a flow that can contribute to the transport of contaminated saliva droplets into the cabin.”
The more people on the elevator are infected with COVID-19, the more damage an air purifier does, the researchers also found.
Professor Drikakis added: “By limiting the number of people allowed in an elevator, the spread of the virus would be kept to a minimum, as well as better design of air purifiers and ventilation systems.”
The findings are published in the journal Physics of Fluids.
Last year a report from Which? warned people that household air purifiers had not been proven to remove 100 percent of Covid particles from a room.
The watchdog said their effectiveness depended on factors such as the size of the room and the type of filter used by the air purifier and age.