Far-UVC (also far-UV or far-UV-C) is light with a wavelength of 200–235 nm. It is a type of germicidal ultraviolet (GUV) light, which includes the whole UVC and parts of the UVB spectrum. Far-UVC has emerged as a highly promising approach to indoor air disinfection, offering enhanced effectiveness and safety compared to conventional 254 nm upper-room GUV systems.
Resources
Blatchley et al. 2022 offer a general overview of far-UVC.
“Far-UVC Light Update: No, LEDs are not around the corner (tweetstorm)” by David Manheim on Lesswrong
“Far-Ultraviolet Light in Public Spaces to Fight Pandemic is a Good Idea but Premature” by Kirby Sikes on Lesswrong