GUV Installations Demonstrate Effectiveness and Exposure Safety in Field Settings

Germicidal ultraviolet (GUV) radiation is used in various building types and indoor applications across the U.S. to mitigate the risk of infection from airborne pathogens. However, to date, few studies have evaluated the in situ effectiveness, safety, and occupant's experience with these installations. To address this gap, we developed and applied a protocol for evaluating in situ performance of whole-room (far UV-C) and upper-room GUV installations. Radiometric and electrical measurements were collected characterizing the spectrum, fluence rate, eye and skin exposure, and energy use of 15 installations. Additionally, a questionnaire asked facility managers and occupants about their satisfaction with the GUV installations. Most installations did not exceed time weighted average limits for eye and skin safety. Findings showed that GUV contributed between 3% to 150% toward meeting ASHRAE 241 equivalent clean airflow targets. These findings support further deployment of these GUV technologies to help inactivate airborne pathogens. The GUV system characterization reported in this article can be used to inform GUV system simulation assumptions.