Ultraviolet C (UVC) light has been used to inactivate several pathogens.
Unlike conventional 254-nm UVC, 222-nm UVC is harmless to human skin
and eyes. UVC with a wavelength of 222 nm had a potent germicidal effect
on vegetative bacterial cells, yeast and viruses, and was as efficient as 245-nm UVC.
In addition, 222-nm UVC had a more potent germicidal effect on bacterial endospores compared with 254-nm UVC. The fungicidal effect of 222-nm UVC against fungal
spores and hyphae was weaker than that of 254-nm UVC. Conclusions UVC with a wavelength of 222 nm was able to inactivate a wide spectrum of microbial pathogens. In comparison with 254-nm UVC, the germicidal effect of 222-nm UVC
 for fungal hyphae and spores was low, but 222-nm UVC had a strong germicidal effect on bacterial endospores.