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

Abstract

Far‐UVC, from filtered Krypton‐Chloride lamps, is promising for reducing airborne transmission of disease. While significant research has been undertaken to investigate skin safety of these lamps, less work has been undertaken on eye safety. There is 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, located on the ceiling and directed downwards into the occupied room. Discomfort was assessed immediately postexposure and several days after exposure using validated, Standard Patient Evaluation Eye Dryness (SPEED) and Ocular Surface Disease Index (OSDI) questionnaires. Our results show no significant eye discomfort or adverse effects from the deployment of Far‐UVC in this simulated office environment, even when lamps were operated continuously with participants receiving head exposures of up to 50 mJ cm−2. In addition, a statistically significant reduction in bacteria and fungi 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.

Eco-Sustainable Approaches to Prevent and/or Eradicate Fungal Biodeterioration on Easel Painting

“…The devastating consequences generated in the health, economy, and education of human society due to the 2019 (COVID-19) pandemic caused by SARS-CoV-2 encouraged research into disinfection systems for pathogens that are harmless to humans. Although 254 nm UV-C lighting is a good microorganism disinfection system, due to its harmful nature to human health, it is considered inadequate radiation for continuous application in indoor areas with an accumulation of people, such as schools, shops, offices, health centers, and hospitals [162]. Therefore, the challenge researchers face is implementing UV-C light in inhabited spaces [163].…”

“…By presenting a penetration of the cells of microorganisms like UV-C (254 nm), its disinfection power is similar. Although its greatest advantage is its lower penetration into the skin's cellular barriers, its harmlessness to mammals [162,164].…”

“…Non-visible radiation, such as UV, can also cause alterations in human health, causing damage to the skin and eyesight, except for Far-UV lighting and visible radiation that are not harmful to mammalian cells [162]. Therefore, using Personal Protective Equipment (PPE), such as protective glasses and clothing opaque to UV penetration, is essential.…”

222 nm far-UVC light markedly reduces the level of infectious airborne virus in an occupied room

“…Recent research has investigated the use of far ultraviolet C (far-UVC) sources for whole-room air disinfection in occupied locations. Far-UVC, typically defined as wavelengths in the range of 200–235 nm, effectively inactivates airborne pathogens 5 – 7 , including SARS-CoV-2, influenza, and other airborne pathogens 8 – 11 , while posing negligible damage to human and rodent skin 12 – 22 and eyes in animal models 23 – 26 as well as in human volunteers 27 – 30 . The mechanistic background relates to the very limited penetration of far-UVC light into living cells in the skin and eyes 31 .…”

222 nm far-UVC light markedly reduces the airborne virus in an occupied room.

“…Recent research has investigated the use of far ultraviolet C (far-UVC) sources for wholeroom air disinfection in occupied locations. Far-UVC, typically defined as wavelengths in the range of 200-235 nm, effectively inactivates airborne pathogens [5][6][7] , including SARS-CoV-2, influenza, and other airborne pathogens [8][9][10][11] , while posing negligible damage to human and rodent skin [12][13][14][15][16][17][18][19][20][21][22] and eyes in animal models [23][24][25][26] as well as in human volunteers [27][28][29][30] . The mechanistic background relates to the very limited penetration of far-UVC light into living cells in the skin and eyes 31 .…”