Far-UVC

The location of 'far-UVC' radiation (200-235 nm) in the electromagnetic spectrum

Far-UVC is a type of ultraviolet germicidal irradiation being studied and commercially developed for its combination of pathogen inactivation properties and reduced negative effects on human health when used within exposure guidelines.[1][2][3][4]

Far-UVC (200-235 nm), while part of the broader UV-C spectrum (100-280 nm), is distinguished by its unique biophysical effects on living tissues. Unlike conventional UV-C lamps (which typically have peak emissions at 254 nm), far-UVC demonstrates significantly reduced penetration into biological tissue. This limited penetration depth is primarily due to strong absorption by proteins at wavelengths below 240 nm.[5] Consequently, far-UVC photons are mostly absorbed in the outer protective layers of skin and eyes before reaching sensitive cells,[6][7] resulting in minimal health effects. However, far-UVC can still lead to negative health effects through reactive byproducts like ozone.

While the technology has been studied since the early 2010s, heightened demand for disinfectant tools during the COVID-19 pandemic played a significant role in spurring both academic and commercial interest into far-UVC. Unlike conventional germicidal UV-C lamps, which are limited to upper-room (above people's heads[8]) pathogen inactivation or use in unoccupied spaces due to their negative effects on human skin and eyes, far-UVC is considered promising for whole-room pathogen inactivation due to its enhanced safety. This allows for the installation of far-UVC lights on ceilings, potentially enabling direct disinfection of the breathing zone while people are present.

Although far-UVC shows potential for implementation in a wide variety of use cases, its wider adoption as a pandemic prevention strategy requires further research around its safety and efficacy.

  1. ^ "Far-UVC Light Can Virtually Eliminate Airborne Virus in an Occupied Room". Columbia University Irving Medical Center. 2024-04-02. Archived from the original on 2024-07-22. Retrieved 2024-07-21.
  2. ^ Morrissey, Janet (2020-06-16). "Fighting the Coronavirus With Innovative Tech". The New York Times. ISSN 0362-4331. Retrieved 2024-07-21.
  3. ^ Welch, David; Buonanno, Manuela; Grilj, Veljko; Shuryak, Igor; Crickmore, Connor; Bigelow, Alan W.; Randers-Pehrson, Gerhard; Johnson, Gary W.; Brenner, David J. (2018-02-09). "Far-UVC light: A new tool to control the spread of airborne-mediated microbial diseases". Scientific Reports. 8 (1): 2752. Bibcode:2018NatSR...8.2752W. doi:10.1038/s41598-018-21058-w. ISSN 2045-2322. PMC 5807439. PMID 29426899.
  4. ^ Blatchley, Ernest R.; Brenner, David J.; Claus, Holger; Cowan, Troy E.; Linden, Karl G.; Liu, Yijing; Mao, Ted; Park, Sung-Jin; Piper, Patrick J.; Simons, Richard M.; Sliney, David H. (2023-03-19). "Far UV-C radiation: An emerging tool for pandemic control". Critical Reviews in Environmental Science and Technology. 53 (6): 733–753. Bibcode:2023CREST..53..733B. doi:10.1080/10643389.2022.2084315. ISSN 1064-3389.
  5. ^ Görlitz, Maximilian; Justen, Lennart; Rochette, Patrick J.; Buonanno, Manuela; Welch, David; Kleiman, Norman J.; Eadie, Ewan; Kaidzu, Sachiko; Bradshaw, William J.; Javorsky, Emilia; Cridland, Nigel; Galor, Anat; Guttmann, Martin; Meinke, Martina C.; Schleusener, Johannes (May 2024). "Assessing the safety of new germicidal far-UVC technologies". Photochemistry and Photobiology. 100 (3): 501–520. doi:10.1111/php.13866. ISSN 0031-8655. PMID 37929787. Archived from the original on 2023-11-09. Retrieved 2024-07-22.
  6. ^ Fukui, Tomoaki; Niikura, Takahiro; Oda, Takahiro; Kumabe, Yohei; Ohashi, Hiroyuki; Sasaki, Masahiro; Igarashi, Tatsushi; Kunisada, Makoto; Yamano, Nozomi; Oe, Keisuke; Matsumoto, Tomoyuki; Matsushita, Takehiko; Hayashi, Shinya; Nishigori, Chikako; Kuroda, Ryosuke (2020-08-12). "Exploratory clinical trial on the safety and bactericidal effect of 222-nm ultraviolet C irradiation in healthy humans". PLOS ONE. 15 (8): e0235948. Bibcode:2020PLoSO..1535948F. doi:10.1371/journal.pone.0235948. ISSN 1932-6203. PMC 7423062. PMID 32785216.
  7. ^ Kaidzu, Sachiko; Sugihara, Kazunobu; Sasaki, Masahiro; Nishiaki, Aiko; Igarashi, Tatsushi; Tanito, Masaki (2019-06-03). "Evaluation of acute corneal damage induced by 222-nm and 254-nm ultraviolet light in Sprague–Dawley rats". Free Radical Research. 53 (6): 611–617. doi:10.1080/10715762.2019.1603378. ISSN 1071-5762. PMID 30947566. Archived from the original on 2022-03-11. Retrieved 2024-07-25.
  8. ^ Reed, Nicholas G. (2010). "The History of Ultraviolet Germicidal Irradiation for Air Disinfection". Public Health Reports. 125 (1): 15–27. doi:10.1177/003335491012500105. ISSN 0033-3549. PMC 2789813. PMID 20402193.