UV-C is an effective disinfection technology that is commonly delivered by UV emitting lamps. Based on International UV Association (IUVA) Fact Sheet UV-C light has been used extensively for more than 40 years in disinfecting drinking water, waste water, air, pharmaceutical products, and surfaces against a whole suite of human pathogens (Fluence UV Dose Required review IUVA). All bacteria and viruses tested to date (many hundreds over the years, including other coronaviruses) respond to UV disinfection. Some organisms are more susceptible to UVC disinfection than others, but all tested so far do respond at the appropriate doses.
UV-C is commonly used as part of a multibarrier strategy for drinking water treatment to protect public health. The same principle can apply in fighting the spread of COVID-19. CDC recommends a layered approach to reduce exposures to SARS-CoV-2, the virus that causes COVID-19. This approach includes using multiple mitigation strategies, including improvements to building ventilation, to reduce the spread of disease and lower the risk of exposure. Use ultraviolet germicidal irradiation (UVGI) as a supplemental treatment to inactivate SARS-CoV-2 when options for increasing room ventilation and filtration are limited. Upper-room UVGI systems pdf icon[6.1 MB, 87 pages] can be used to provide air cleaning within occupied spaces, and in-duct UVGI systems can help enhance air cleaning inside central ventilation systems.