Naomi Wu, before getting cancelled by the Chinese Government did a phenomenal job advocating and advancing technology in this space.
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Can ultraviolet lightbulbs end the next pandemic before it starts?
51–60 of 61 posts
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#52The concept is good [1], but the hardware is crappy. There's a lot of fake junk out there. The fake junk comes in two forms - UV lights that emit in dangerous parts of the spectrum, and UV lights so weak as to be at "homeopathic levels". Lamps that emit around 222nm are significantly more expensive than the wrong lamps. Typical fake on eBay.[3] Previously on HN: [2] [1] https://www.nature.com/articles/s41598-020-6721…
What kinda fake is that one on Ebay? Dangerous or homeopathic?
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#53I sterilize my N95/KF94 masks with UV light for reuse. If anyone wants to follow suit, beware fake UV bulbs. Test your product / bulb with a banana. Put masking tape on the banana, then expose the banana to the light for a few hours. If the band develops a suntan except for under the tape, you've got a good bulb. It should kill any bacteria and certainly any viruses on your mask. But still throw out your masks when t…
>If the band develops a suntan except for under the tape, you've got a good bulb.
Beware, heat from the lamp can also cause a "suntan". That's why checking under the tape is a mandatory step. If even under the tape is tanned, it is caused by heat and the test is invalid.
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#54UV light is also pretty bad for humans, is it not? Sunburn, skin-cancer, and all that. I seem to recall a recent mistake where some UV disinfectant lights were used at an event, resulting in sunburns and eye problems for many attendees. The article does address this and is talking about a variety of techniques for UV light that has less exposure to people and doesn't result in immediate harm. But presumably this woul…
As described in the article, far UV does not appear to be directly dangerous to humans at all. However it does produce Ozone, which can be dangerous - the question is how significant that would be in real, world settings, which is being studied.
Study it all they want, I really don't want to be under artificial UV in an office setting for 8-10 hours a day. Especially since the germs will eventually become immune to it under such persistent steady evolutionary stress. We have enough cancer contributing technologies in our life already without adding more ozone and UV.
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#55The concept is good [1], but the hardware is crappy. There's a lot of fake junk out there. The fake junk comes in two forms - UV lights that emit in dangerous parts of the spectrum, and UV lights so weak as to be at "homeopathic levels". Lamps that emit around 222nm are significantly more expensive than the wrong lamps. Typical fake on eBay.[3] Previously on HN: [2] [1] https://www.nature.com/articles/s41598-020-6721…
What kinda fake is that one on Ebay? Dangerous or homeopathic?
By the looks of it the LED's are in plastic cases. The actual UV LED's that can be used fro sterilization come in metal cases with glass windows. And they cost multiple dollars per LED. Basically the LED's on that product are the wrong frequency to be effective. 300-400nm instead of 250nm.
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#56Earlier quoted context omitted.
Personally I feel the use of the term "far uv" is very misleading because the 220 nm wavelength is within UVC, and not too far away from 254 nm germicidal UVC. It is always helpful to consult a chart: http://www.drb-mattech.co.uk/uv%20spectrum.html So, from a public health/public education standpoint, I find it troubling that scientific research, which the article points out, is limited in this area. For decades, gen…
As I understand it, the point of 222nm is NOT to sterilize organic tissue directly. The point of 222nm is to able to use it for sterilization in things like air return ducts, industrial cleaning equipment, etc. Since 222nm is relatively "safe", you don't have to worry some idiot opening up a system, giving himself a gigantic flux of UV in the face, and winding up in the ER for cornea burns. Consequently, your mainten…
This is the point of mechanical/electrical interlocks to prevent exposure to energized UVC. This is why I find the attempt to make 'far uv' safe in the public conscious even more dangerous.
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#57[deleted]
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#58Why not put the uv lights in the hvac systems?
That’s what I did a few years ago. Drill a hole in the side of the air handler and mount it in there. https://mrscrappy.com/products/uv-c-air-sanitizer
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#59Earlier quoted context omitted.
> I suspect that subjecting people indoors to an amount of UV radiation comparable with a day outside might be OK And I suspect this is very incorrect. UV is beneficial at low quantities, but has serious negative impacts on human health at high quantities.[1] Your mention of using it in common areas (where individuals would only be for a few minutes a day) seems much more reasonable. [1] https://en.wikipedia.org/wiki…
The far UV spectrum being talked about here is not the same as conventional UVC germicidal lamps, nor the same as UVA/B from the sun. UV is only dangerous because at UVC wavelengths it penetrates cell nucleii and damages DNA. The interesting thing about far UV though is that while it will still damage DNA, it can't penetrate regular cells - it's blocked by the cell membrane/proteins. But viral particles don't have a…
> The far UV spectrum being talked about here is not the same as conventional UVC germicidal lamps, nor the same as UVA/B from the sun.
I was responding to someone suggesting outside-levels of UV exposure. If we're talking about a different wavelength, I am even more doubtful of the safety.
Re: Can ultraviolet lightbulbs end the next pandemic before it starts?
#60I built some prototypes with far-UVC, ie UV but safe for human exposure (and pets!), as in the article. Specifically this one: https://www.care222.com At the end of the day it’s tutorial 1 in every arduino project, just replace the led with a far-UVC lamp. Unfortunately the price is extreme, so very hard to commercialize. I installed one in my entrance… I’m currently sterilizing my shoes :)
On the site "Care222modules use an excimer lamp in combination with a special optical band pass filter that blocks the ultraviolet wavelengths that could have a harmful effect on people. Care222 is the only Far UV-C product in the world with this key technology." why is this key technology so difficult? And why is the product so expensive?
Looking at uvb there use to be several afordable manufacturers with good test data but they all closed shop. What is left either doesnt work or is scarry expensive.
The lamps are cheap the coating is hard to develop. Im not sure but it seems if you want to produce it you have to redo the rnd to figure out how.