Technology Briefing: Upper-Air UV Disinfection Devices
September 10, 2020 | Evaluations & Guidance
Here's a briefing on upper-air UV disinfection devices, outlining the key considerations for making wise purchasing decisions. **We review how and where the technology is used, which applications it is best suited to, the strength of the evidence to support its use, and more.
Upper-air UV disinfection systems are installed high in an occupied room, above the occupied space, to disinfect the air. They rely on circulation of the air to bring "dirty" air from the occupied space up into the disinfection zone, and to return the disinfected air to the occupied space.
To be considered in this category, a product must be installed in the upper part of a room, above the occupied space. It must emit UV light in a directional manner, with the intention that the light stays in the upper portion of the room, away from the occupants. The UV light must have a germicidal effect, which can be achieved by emitting wavelengths in the UVC range (200-280 nm). These systems most commonly use 254 nm light.
Upper-air UV disinfection technology has been available for decades. However, in the past, implementation appears to have been focused on tuberculosis applications, due to the airborne nature of the bacteria. ECRI has noticed an increase in the number of requests on this topic, in light of the COVID-19 pandemic. The technology is mature and has shown only incremental changes, such as improvements in UV intensity, energy efficiency, and aesthetics.
The major components of these systems include a wall- or ceiling-mounted UV light source; blinds, reflectors, or guards to direct the light horizontally or upward; and, optionally, a fan to help circulate air.
Below, we indicate the decontamination/sterilization functions that upper-air UV room disinfection systems...