Notes, further reading, citations, studies, videos.......
A supplemental guide for Fan-Club’s Far-UVC Workshop!
still adding some stuff 3/15!!!
Please email if you have additional questions or stuff that I should include here!!! Much of this will be simplified and added to http://wehavethetools.neocities.org/ at some point...
If you know anyone who wanted to join but couldn’t, they can sign up for the next presentation at http://skillshares.fan-club.cc
VARIOUS RESOURCES I FOUND HELPFUL!
(Overviews/less specific research/videos)
Ultraviolet light can kill almost all the viruses in a room. Why isn’t it everywhere? - Dylan Matthews, Jan 2024
Video version of above article:UV light kills viruses. Why isn't it everywhere? - VOX
Far UV-C radiation: An emerging tool for pandemic control - Ernest R. Blatchley III, David J. Brenner, Holger Claus, Troy Cowan, Karl G Linden, Yijing Liu, Ted Mao, Sung-Jin Park, Patrick J. Piper, Richard M Simons, David Sliney. June 2022
Germicidal UV-C as a Means of Sterilization in the Post-COVID World: What does the Science Say? David H. Sliney, Ph.D. ICNIRP SEG Johns Hopkins School of Public Health Slides from a presentation at a symposium in Japan in 2022
Type of ultraviolet light most effective at killing coronavirus is also the safest to use around people, Karl Linden, October 2021
How does Far-UVC effect COVID?
First, how does a virus infect the cells??
A Virus Attacks a Cell - Animation by Vaccine Makers Project Cool video!!
Viral Inactivation by Light - Mohammad Sadraeian, Le Zhang, Farzaneh Aavani, Esmaeil Biazar, Dayong Jin. 2022.
*Apologies -- realized the chart I included in my slides from the above study shows only ionizing gamma rays vs. UV-B effects; I believe UV-C works similarly but am looking into it more now! -kj 3/15
This chart is about 222 nm:
Wavelength-specific inactivation mechanisms and efficacies of germicidal UVC for airborne human coronavirusSAFETY
1. CERTIFICATIONS/RECOMMENDATIONS/REGULATIONS
TLVs are workplace exposure standards recommended by a committee of the American Conference of Governmental Industrial Hygienists (ACGIH)
A Need to Revise Human Exposure Limits for Ultraviolet UV‐C Radiation - David Sliney, Bruce Stuck, March 2021
Panel: Regulatory Pathways Roundtable - 1st International Congress on Far-UVC Science and Technology
Video of panel featuring representatives from NIOSH, EPA, and others – explaining how their agencies contribute to regulating far-UVC
ICNIRP (International Commission on Non-Ionizing Radiation Protection)
ICNIRP recommends 23 mJ cm² per 8hr exposure to UVC wavelengths between 180 nm to 280 nm (last updated 2004) Boeing paper recommending updates/helpful background and resources: Safety of 222 nm Band-Pass Filtered Irradiation: A Review and Analysis of Current Data - Casey Brantner, Angela Wong, Angela Davis, Celestia Hammond, Nels Olson*
ACGIH (American Conference of Governmental Industrial Hygienists)
ACGIH’s TLV recommendation: 160 mJ cm² for eye exposure and 480 mJ cm² for skin (as of 2022)
Some info on the EPA and FIFRA
"UV lights that are sold or distributed with claims that the product can be used for preventing, destroying, repelling or mitigating any pest (plant, animal, virus, bacteria or other microorganism) are federally regulated by EPA under FIFRA"
CARB (California Air Resources Board)
UL (Underwriters Laboratories) – UL 2998 Zero Ozone Emissions Validation
2. Skin and Eyes:
Ocular Safety of 222-nm Far-ultraviolet-c Full-room Germicidal Irradiation: a 36-month Clinical Observation - Kazunobu Sugihara, Sachiko Kaidzu, Masahiro Sasaki, Sho Ichioka, Ichiya Sano, Katsunori Hara, Masaki Tanito, December 2024
*Potential conflict of interest-study funded by Ushio, Inc. a company that sells 222nm devices.
Example of how TLV is calculated (intensity x time)
Nukit’s Torch is 6.8 µW/cm² at 50cm
ACGIH Eye TLV Exposure Limit is 160.7 mJ/cm²
This means it's eye-safe for 6.57 hours
Nukit’s Torch is 6.8 µW/cm² at 50cm
ACGIH Eye TLV Exposure Limit is 160.7 mJ/cm²
This means it's eye-safe for 6.57 hours
FYI! 3.7 mJ/cm² is needed to inactivate SARS-Cov-2!
What dose of UV is necessary for other viruses? Interesting chart at 1:58 (video)
4. OZONE/AIR:
The public-health significance of far-UVC-induced indoor ozone and its associated secondary chemistry - David J. Brenner, November 2023
Ozone Generation by Ultraviolet Lamps - Holger Claus, February 2021
"Ozone has been shown to affect the respiratory, cardiovascular and central nervous systems. It is highly regulated (e.g. EPA, FDA, ACGIH, NIOSH), and exposure limits have been established. There are various standards (e.g. UL867) and guidelines for ozone, especially for air cleaners."
"...turning off far-UVC lights during cleaning with limonene products would be reasonable..."
HISTORICAL AND CONTEMPORARY USES OF UV FOR HEALTH AND SANITATION
Here's a timeline I'm working on/some of my additional notes
We’ve Been Killing Deadly Germs With UV Light for More Than a Century - Allison Marsh, Aug 2020
A Brief Report on the History of Phototherapy - Andrzej Grzybowski, Jarosław Sak, Pawlikowski, May 2016
Ancient Light Therapies: A Boon to Medical Science - Nishant Gupta, Poonam Gusain, July 2018
Sunlight in Tuberculosis - A.R. MASTEN, September 1935 (for full text, email me!)
The Environmental Control of Epidemic Contagion I: an Epidemiologic Study of Radiant Disinfection of Air in Day Schools - WF Wells, MW Wells, TS Wilder, July 1941
The History of Light Therapy - Glenn Ruscoe, March 2023
How UV Light is Used in Hospitals and Medical Facilities – Larsen Electronics 2 min video
Exploring the Application of UV Light in HVAC Systems - DucTales, July/August 2023
The Impact of Heating, Ventilation, and Air Conditioning Design Features on the Transmission of Viruses, Including the 2019 Novel Coronavirus: A Systematic Review of Ultraviolet Radiation - Gail M Thornton, Brian A Fleck, Natalie Fleck, Emily Kroeker, Dhyey Dandnayak, Lexuan Zhong, Lisa Hartling, April 2022
About Germicidal Ultraviolet (GUV) - CDC/NIOSH
NYC implements 254 nm UVC in MTA subway system (unaccompanied cars/before opening) in 2020 — News segment/interview
PRACTICAL USES FOR TODAY - FAR-UVC 222 nm
Help with visualizing placement from NUKIT222
