#222nm — Public Fediverse posts

Far-UVC and Eye Safety: Findings from a 36-Month Study (Jan 2025) uvmedico.com/news/far-uvc... #FarUVC #222nm #IAQ #AirbornePathogens #CovidisAirborne

Far-UVC and Eye Safety: Findings from a 36-Month Study (Jan 2025) uvmedico.com/news/far-uvc... #FarUVC #222nm #IAQ #AirbornePathogens #CovidisAirborne

@masknerd in the back of my mind is the importance of understanding irradiance and hence exposure time as a function of distance from the lamp.
It may be easier with a ceiling installation and guaranteed minimum distance from occupants, but portable devices could inadvertently be held at a distance that could result in orders of magnitude higher exposure if device design does not compensate for this risk (eg proximity shutoff/alarm)
#Faruv #222nm

I just found a smart #Twitter thread on the ins and outs of 222 nanometer far-ultraviolet light, which I think could help end #Covid forever:

https://t.ly/6jw_

@joeyfox85 is an engineer who tweets about anti-Covid engineering. I made a #bot to follow him on #Mastodon: @joeyfox85 (works on my instance, YMMV) 

TL;DR: #222nm UVC light kills Covid (and #MRSA, #RSV, #flu, etc.) but doesn't burn skin or eyes like the 254nm UVC used now for disinfection (and tanning beds).

A 20w 222nm bulb can disinfect a room in 5-10 minutes with no risk to people or animals. 222nm LEDs could be even added to regular LED bulbs to disinfect every room in your house.

But the tech has only existed since 2020, so it's expensive: $1000/bulb, as opposed to $50/bulb for 254nm. And it hasn't been tested enough to know if it's safe for the skin biome or people with #AutoImmune disorders.

The problem is that almost nobody makes 222nm lights. If we made them at the scale we make 254nm, prices would plummet.

@debihope @BlackAzizAnansi I bought a Kickstarter #Mask in 2020 that shines UV light on the air as it goes in the mask, but not for long enough to kill #Covid. If the UV LED was outside the mask, it would do a better job of disinfecting the air, but then it would burn or blind me - it uses 254nm UVC light, the same kind tanning beds use.

What I really want is a mask or a headlamp with the new #222nm LEDs. 222nm UVC light kills Covid in minutes, but can't burn skin or eyes like 254nm.

@SexyCyborg is a #maker in #Shenzen who built a personal 222nm projector: http://tny.wtf/Y Naomi is a great person to follow for her insight on fighting Covid.

Unfortunately, 222nm lights cost $$$ everywhere that isn't Shenzen. In the US I can get a 20w 254nm bulb for $20, but a 20w 222nm light is $1000-$2000.

If the US took disinfection seriously, we could jumpstart a 222nm industry and put them in light fixtures everywhere for cheap, but we don't take much about Covid seriously.

Thread summarizing the promise of Far-UVC (#222nm):

https://twitter.com/joeyfox85/status/1608674677177880581

Very promising for #covid, but also hard to get right and use safely. Even the comments following the thread show how poorly people understand the subtleties (eg, thinking UVC has anything to do with CO2). Not only is more study needed, devices will need careful testing to ensure they only emit in the narrow band, and there's huge opportunity for dangerous, misleading and/or ineffective products. 1/3