Far UVC ultraviolet light is thought safe for humans, and deactivates 99.9% of airborne coronavirus in 25 mins

Hip

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Standard germicidal UVC ultraviolet light with a wavelength of 254 nm is routinely used to disinfect hospital rooms and toilets when humans are not present, but is not safe to use when people are there, since this light has harmful effects on human skin, and is linked to skin cancer.

However, far UVC ultraviolet light at a slightly shorter wavelength of 222 nm is found to kill pathogens including SARS-CoV-2 with similar efficiently even at very low doses, but potentially without harm to exposed human tissues or eyes. The wavelength of 222 nm is unable to penetrate human skin or eyes, so cannot reach the cells, making it safe potentially.

See this June 2020 paper: Far-UVC light (222 nm) efficiently and safely inactivates airborne human coronaviruses.

The paper shows that low levels of far UVC in a room deactivates 99.9% of airborne coronavirus in 25 minutes.



This 222 nm far UVC light would be very useful in public spaces like bars, restaurants, shops, supermarkets and public transport, to destroy the coronavirus particles floating in the air, if it proves to be as safe as is believed.

Here are some articles on this new way to tackle COVID:

Looks like some 222 nm far UVC coronavirus-killing products are already in the pipeline:
 
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SWAlexander

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Hip thanks. UV has helped me all my life (60 y.) with psoriasis and low Vit D. I never got skin cancer. Since I´m in the tanning studio again I feel much better.
In the old days in Germany, women hung the comforter and pillows out of the window for at least a half-hour every day (except Sunday). My grandma told me then, the sun will kill the bacteria.
 
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Yes the sun does kill the dust mites. Makes sense it might kill the bacteria too. Mind you needs to be very hot or cold to work on dust mites.

I wonder if this could be repurposed as a visor that showers the persons nose and mouth with this light. So that when they breath in any virus is dead. But as it says 25 minutes probably not.
 

Hip

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I wonder if this could be repurposed as a visor that showers the persons nose and mouth with this light. So that when they breath in any virus is dead. But as it says 25 minutes probably not.
I read some studies looking into the possibility of using germicidal UVC air purifiers to sterilize coronavirus. UVC air purifiers have been around for some time, and you can buy them quite cheaply.

However, the studies found that the short exposure to ultraviolet that the air gets when traveling through the air purifier is not long enough to disable the virus, even when high power ultraviolet light is used. So unfortunately I expect it would not work in a visor either.
 

SWAlexander

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I read some studies looking into the possibility of using germicidal UVC air purifiers to sterilize coronavirus. UVC air purifiers have been around for some time, and you can buy them quite cheaply.

However, the studies found that the short exposure to ultraviolet that the air gets when traveling through the air purifier is not long enough to disable the virus, even when high power ultraviolet light is used. So unfortunately I expect it would not work in a visor either.
I use a " Pur UV 36 W 110 V Licht Digital Control Sterilisation".
 

Hip

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Yes, that's the standard 254 nm germicidal ultraviolet light that's not meant to be used to disinfect when humans are present, as there is an increase risk for skin cancer and cataracts. Although it is used to treat psoriasis in small doses.

Incidentally, when I took an antioxidant called tempol at a dose of 30 mg daily sublingually, this permanently cured a 3-inch size circular patch of psoriasis near my ankle after 10 days.
 
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Yep I figured duration was an issue. 25 minutes is a long time for any handheld use. But good for clincisl cleaning I guess? Or filtered chamber exposure to the right light before that air is then passed out into a central ventilation system. Would kill many nasties.
 

SWAlexander

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Yes, that's the standard 254 nm germicidal ultraviolet light that's not meant to be used to disinfect when humans are present, as there is an increase risk for skin cancer and cataracts. Although it is used to treat psoriasis in small doses.

Incidentally, when I took an antioxidant called tempol at a dose of 30 mg daily sublingually, this permanently cured a 3-inch size circular patch of psoriasis near my ankle after 10 days.
"disinfect when humans are present" I use it in a room for 20 min with nobody in it and the door closed.
I have psoriasis but I never heard of tempol.

Just found this: Tempol for SOD and catalase deficiency in psoriasis
https://tempol.info/tempol-may-sod-and-catalase-deficiency-in-psoriasis/
Not available in Germany.
 
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Cipher

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Yes, that's the standard 254 nm germicidal ultraviolet light that's not meant to be used to disinfect when humans are present, as there is an increase risk for skin cancer and cataracts. Although it is used to treat psoriasis in small doses.
Only UV-B & UV-A is used for psoriasis, not UV-C.
 
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