The results of the first study conducted on the disinfection efficiency of UV-LED irradiation at different wavelengths or frequencies on a virus from the coronavirus family arrive.
The study was conducted by the professor Hadas Mamane, head of the Environmental Engineering Program at TAU's School of Mechanical Engineering, Iby, and Aladar Fleischman Faculty of Engineering. The article on UV-LEDs was published in the Journal of Photochemistry and Photobiology. And the results bring an interesting proposal that could concern ventilation systems.
A good light
“The whole world is currently looking for effective solutions to disinfect against the coronavirus,” says Mamane. “The problem is that disinfecting a surface or a ventilation system on a bus, a train, a sports hall or an airplane with chemical spraying requires a lot of manpower. For spraying to be effective, then, it is necessary to give the chemical substance time to act on the surface.”
Disinfection systems based on LED bulbs, however, can be installed in ventilation systems, sterilizing the air sucked in and released back into the environment.
Put a UV-LED in the aerator
“We found that it is quite simple to kill the coronavirus using UV-LED bulbs, that is, LED bulbs that radiate ultraviolet light,” Mamane explained.
“With the right setup it is possible to kill viruses using cheaper and more readily available LED light bulbs, which use little energy and do not contain mercury like regular light bulbs. Our research has commercial and social implications, given the possibility of using such UV-LED bulbs in all areas of our lives, safely and quickly."
What wavelength affects Covid?
In this study the researchers tested the optimal wavelength for killing the coronavirus and rated a length of as suitable 285 nanometers (nm). The same effectiveness, in fact, as a wavelength of 265 nm, which requires less than half a minute to destroy more than 99,9% of the coronavirus. This is a significant achievement, because the cost of 285nm LED bulbs is much lower than that of 265nm bulbs, and the former are also more readily available.
Eventually, as science develops, the industry will be able to make the necessary changes and install UV-LED bulbs in robotic systems or air conditioning, vacuum and water systems, and thus efficiently disinfect large surfaces and spaces. Professor Mamane believes the technology will be available for use in the near future.
It is important to point out (you never know) that it is very dangerous to try to use this UV-LED method to disinfect surfaces inside homes. To be fully effective, a system must be designed so that a person is not directly exposed to light.
In the future, the researchers will test their unique combination of integrated damage mechanisms and other recently developed ideas about efficient direct and indirect combined damage to bacteria and viruses on different surfaces, air and water.
The study was conducted in collaboration with Professor Yoram Gerchman of Oranim College; Dr. Michael Mandelboim, Director of the National Center for Influenza and Respiratory Viruses at Sheba Medical Center in Tel HaShomer; And Nehemya Friedman by Tel Hashomer.
We hope to find a light at the bottom of the ventilation systems, forget about the tunnels.
The research paper is available on the journal's website here.
Contacts and sources:
Publication: UV-LED disinfection of Coronavirus: wavelength effect. Yoram Gerchman, Hadas Mamane, Nehemya Friedman, Michal Mandelboim. Journal of Photochemistry and Photobiology B: Biology, 2020; 212:112044 DOI: 10.1016 / j.jphotobiol.2020.112044
