question: Is ultraviolet germicidal irradiation (UVGI) recommended for disinfection of air and surfaces in the healthcare setting?
answer: UVGI can be used as a supplemental treatment for disinfection of air in HVAC systems or above people in occupied spaces (upper-room or upper-air systems) and for supplemental disinfection of surfaces following routine cleaning and disinfection. UVGI, also known as Germicidal Ultraviolet (GUV), uses ultraviolet energy in the UV-C band (wavelengths of 220-280 nanometers), which is effective against SARS-CoV-2 under laboratory conditions. Efficacy of the applied dose (a function of irradiance and time) is highly dependent on many factors, such as the concentration of the virus, inoculum size (in experimental studies), the virus medium, contours and type of material being treated, as well as what the virus is suspended in (e.g., culture media, respiratory droplets, other proteinaceous material). These complex variables may explain the range of results presented in the published literature. For more information on these technologies see the CDC Business FAQs under the heading Cleaning and Disinfection in the Workplace UV-C can be applied on healthcare environmental surfaces using robots as NTDs following terminal cleaning and is still considered investigational; one study mentioned above the Duke BETR Disinfection Study (Andersen DJ, et al. Lancet Infect Dis 2018; 18(8): 845–853) has shown a decrease in Healthcare-associated infections.