Scientists are developing UV light tech for city-wide coronavirus disinfection
When it was confirmed that the novel coronavirus can stay on surfaces for hours, governments began deploying disinfection techniques to keep public spaces sanitized. The effort led many experts to suggest that UV light could be an effective tool in killing the virus. Now, scientists are building on that suggestion and optimizing the method into a technology capable of disinfecting entire cities. Here's more.
For years, scientists have known that UVC light in the 200-300 nanometer range can destroy viruses/bacteria on a cellular level, making them incapable of reproducing and infecting. The method was tested against the novel coronavirus (SARS-CoV-2) and it proved highly effective in eradicating the pathogen from different surfaces and objects. The success led to the deployment of the UVC disinfection system across countries.
Given UVC's promise, Bengaluru-based nanotechnology start-up Log 9 Materials created the 'CoronaOven' object disinfection chamber using the technology. Then, DRDO also employed the same idea and came up with dedicated UVC-based disinfection cabinets for mobile phones, iPads, laptops, currency notes, cheque leaves, challans, passbooks, and other paper-made materials. Similarly, other nations used the method for disinfecting subway cars, buses, and hospitals.
While the disinfection method has proven valuable in sanitizing objects, it has also been associated with certain problems, issues that prevent its broader usage. For instance, there have been studies that show UVC light can cause skin irritation and cancer in humans. Plus, there is also the problem of UVC source, mercury gas, being very expensive, short-lived, and bulky to be carried around.
To tackle these issues and make UVC safe for city-wide disinfection, two separate teams are working on workarounds. One group, hailing from Columbia University, has carried out experiments to determine that "far-UVC" rays (at the far end of the light spectrum), when applied at a wavelength of 222 nanometers, can kill the novel coronavirus without causing any kind of harm to humans.
The second team, from Penn State University and the University of Minnesota, is exploring the use of a film made from strontium niobate, a chemical compound used in a variety of optics, to replace the mercury gas as the source. They are working to use this film for creating a handheld UV-based LED that could disinfect surfaces while being portable, long-lasting, and energy-efficient.
Once a safe UV-emitting device is developed, it could be deployed across various parts of the city and powered on like street lights to carry out instant COVID-19 disinfection. This can save a lot of government resources during this crisis.