In 2023 there was a conference about Chemistry of Indoor Environments (CIE) that looked at the research that was done over a ten-year period; opening presentation:

* https://www.youtube.com/watch?v=vt0GLbi20Q4

* https://indoorchem.org/publications/

Playlist of the various presentations from the conference:

* https://www.youtube.com/watch?v=J2iHOCI2hz4&list=PLsc2-5fAgM...

Generally: avoid any use of electronics to 'do stuff' to the air or pathogens (e.g. UV) and just use high-MERV / HEPA filters, and use an ERV to vent stale air and bring in (filtered, conditioned) outside air.

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thepaulmcbride a day ago | parent | next [-]

Even HEPA isn’t a requirement, you just need a high CADR. Doesn’t matter if the filter doesn’t catch a particle on the first pass as long as it does one a subsequent one and the flow rate is high!

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rogerkirkness a day ago | parent | prev [-]

Yeah the whole 'just use HEPA' has been what's worked for us after about a half dozen different air purifiers of experimentation. I noticed the positive ionization things changed my heart rate variability which was spooky.

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o11c a day ago | parent [-]

Empirically, the ionizer is good for wildfire season, but the rest of the year HEPA is good.

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throw0101c a day ago | parent [-]

> Empirically, the ionizer is good for wildfire season, but the rest of the year HEPA is good.

Smoke can be dealt with via a carbon filter and you don't have to do a chemistry experiment in your house.

* https://shop.aprilaire.com/search?q=Carbon+Air+Filter

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o11c a day ago | parent [-]

Empirically, no it doesn't, at least not for the quantities of smoke we get in wildfire season. It's probably enough for most "abandoned industry on fire again" fires, if that's all you get?

	▲	throw0101c a day ago \| parent [-]
		Per the EPA: > Upgrading to a filter rated MERV 13 or higher can be especially important during smoky periods to effectively remove fine particle pollution from smoke in the indoor air. * https://www.epa.gov/wildfire-smoke-course/preparing-fire-sea... The carbon is for the smell. The EPA also points to this California list, which include "mechanical" types which do not use electronic measures: * https://ww2.arb.ca.gov/list-carb-certified-air-cleaning-devi... The main challenge is the resistance to airflow (US: inches w.c.) that can be a problem with for HVAC equipment, which is why you want a large surface area, e.g.: * https://electronicaircleaners.com/docs/aprilaire_2416_2216_a... * https://www.aprilaire.com/whole-house-products/air-purifiers...