Are you looking for a project where you could substantially improve indoor air quality, with benefits both to general health and reducing pandemic risk?

I've written a bunch about air purifiers over the past few years, and its frustrating how bad commercial market is.

The most glaring problem is the widespread use of HEPA filters. These are very effective filters that, unavoidably, offer significant resistance to air flow. HEPA is a great option for filtering air in single pass, such as with an outdoor air intake or a biosafety cabinet, but it's the wrong set of tradeoffs for cleaning the air that's already in the room. Air passing through a HEPA filter removes 99.97% of particles, but then it's mixed back in with the rest of the room air. If you can instead remove 99% of particles from 2% more air, or 90% from 15% more [...]

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First published:
May 11th, 2025

Source:
https://www.lesswrong.com/posts/bBX46cBpbruv2kJh5/better-air-purifiers

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Narrated by TYPE III AUDIO.

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Images from the article:

Air filters arranged in octagonal shape around ceiling fan.

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“Better Air Purifiers” by jefftk

LessWrong (30+ Karma)