222 nm Far-UVC from filtered Krypton-Chloride excimer lamps does not cause eye irritation when deployed in a simulated office environment

Abstract

AbstractFar-UVC, in the form of filtered Krypton-Chloride lamps, is a promising technology for reducing airborne transmission of disease. Whilst significant research has been undertaken to investigate skin safety of these lamps, less work has been undertaken on eye safety. In particular, there is very limited data on human eye safety or discomfort from the deployment of this germicidal technology. In this pilot study, immediate and delayed eye discomfort were assessed in a simulated office environment with deployment of Krypton-Chloride lamps. The discomfort was assessed immediately post-exposure to the Far-UVC and several days after exposure using the validated, standardized Standard Patient Evaluation Eye Dryness (SPEED) and Ocular Surface Disease Index (OSDI) questionnaires. Our results show that there was no significant eye discomfort or adverse effects from the deployment of Far-UVC in this simulated office environment, even when the lamps were operated continuously. In addition, through collection of bacteria and fungi on agar plates, with this non-optimised lamp arrangement a statistically significant reduction in pathogens of 52% was observed. Far-UVC in this simulated office environment did not cause any clinically significant eye discomfort and was effective at reducing pathogens in the room. These results contribute an important step to further investigation of the interaction of Far-UVC with the human eye.