Safe UV air purification
According to a new study conducted at Columbia University, more than 99.9% of seasonal coronaviruses present in airborne droplets were destroyed by exposure to ultraviolet radiation of a certain wavelength, which is safe for humans. Conventional bactericidal ultraviolet radiation (wavelength 254 nm) can be used to disinfect empty rooms, such as unused hospital wards or subway cars, but direct exposure to these conventional ultraviolet lamps in the presence of people is impossible, as they pose a health hazard.
In order to continuously and safely disinfect occupied premises, the researchers used far ultraviolet light (Far Ultraviolet, FUV) with a wavelength of 222 nm. It cannot penetrate through the tear film of the eye or the outer layer of keratinized skin cells and therefore cannot damage living cells in the body.
Previously, researchers have shown that FUV radiation is capable of killing flu viruses in the air and is safe for humans. A new article is devoted to the study of seasonal coronaviruses that are structurally similar to the SARS-CoV-2 virus.
The researchers placed two types of common coronaviruses in aerosols, which were then sprayed in the air in front of a FUV-emitting lamp. After that, the researchers checked how many viruses remained, and found that more than 99.9% were destroyed with very little exposure to FUV.
Researchers have calculated that constant exposure to FUV radiation can destroy 90% of viruses in the air in 8 minutes, 95% in 11 minutes, 99% in 16 minutes and 99.9% in about 25 minutes.
The sensitivity of coronaviruses to FUV suggests that it is advisable to use such lamps in public areas in order to significantly reduce the risk of human-to-human transmission of coronaviruses, influenza viruses and others.
The group is already conducting a new study to test the effectiveness of FUV against the airborne SARS-CoV-2. Preliminary data suggest that FUV lamps will be just as effective at destroying SARS-CoV-2.
If successful, FUV emitters can be installed in hospitals, buses, planes, trains, train stations, schools, restaurants, offices, theaters, gyms and so on. In combination with other protective measures – wearing masks and frequent hand washing with soap, this will help limit the transmission of SARS-CoV-2 and other viruses.
Article by M.Buonanno et al. Far-UVC light (222 nm) efficiently and safely inactivates airborne human coronaviruses is published in the journal Scientific Reports.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru Based on the materials of Columbia University Irving Medical Center: Far-UVC Light Safely Kills Airborne Coronaviruses.