ai6yr, The most useful invention I've ever run across... Corsi-Rosenthal box.
I have used this so far for:
- Wildfire smoke
- COVID-19
- Bacon smoke (on Saturdays, LOL)
- General improvement of AQI
- Pet related allergies (hay and dander)
- Ragweed/pollen heavy days
- Dust from Santa Ana winds
- Dust from construction/remodeling
- Paint fumes (only partially useful, doesn't absorb gases, but helps somewhat) -- plus it sucks all the dust from the air, so it doesn't stick to your paint
(probably other uses, too...)
How to build one:
https://engineering.ucdavis.edu/news/science-action-how-build-corsi-rosenthal-box