Upper-room UVGI systems have been used safely and effectively for decades. However, UV energy directed or reflected into the occupied space has the potential to cause temporary eye or skin damage. Assistance from a qualified HVAC professional or a reputable UV system manufacturer will ensure the system is installed properly so UV energy is directed above occupied space and operates safely.
The systems should be connected to designated electrical switches with limited access to the public and staff or volunteers not trained in managing the system. For example, consider using lockable switches or placing switches in a restricted area that only trained staff can access using a lock and key. This prevents the UV lamps from being turned on or off unintentionally and allows the fixtures to be safely powered off when necessary without fear of them being powered on during maintenance.
Influenza viruses are more susceptible to UV energy than the bacteria that causes TB. Thus, any upper-room UVGI system installed to help during the COVID-19 pandemic will also be useful against seasonal flu, if it is properly maintained. 3
UV-C energy can damage plants placed in the disinfection zone (for example, on the top of tall bookcases or high shelves). The energy can also cause fading and cosmetic blemishes to wood surfaces and wallpapers (most wall and ceiling paints are not affected). Thus, care should be taken when installing upper-room UVGI systems in spaces with ornate architectural elements and plants.