Far-UVC is something people have talked about for years in a "that would be great, if you could buy it" sort of way. Coming soon, once someone actually makes a good product. But the future is now, and it costs $500.

Many diseases spread through the air, which is inconvenient for us as creatures that breathe air. You can go outside, where the air is too dilute to spread things well, but it's cold out there, and sometimes wet. You can run an air purifier, but cleaning lots of air without lots of noise is still the world of DIY projects. Ideally you could just shine some light, perhaps in the 222-nm range, which would leave people alone but kill the viruses [1] and bacteria. Yes, let's do that!

Last year if you asked "if far-UV is so great, why isn't it everywhere?" one of your answers would be:

There are very few providers, and hardly any of them sell an off-the-shelf product. You usually can't just buy a lamp to try it out—you have to call the company, get a consultation, and often have someone from the company come install the lamp. It's a [...]

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First published:
December 13th, 2025

Source:
https://www.lesswrong.com/posts/fMbk6tFH7KPJEwcdi/you-can-just-buy-far-uvc

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Narrated by TYPE III AUDIO.

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“You Can Just Buy Far-UVC” by jefftk

LessWrong (30+ Karma)