[5e92cb50239222b]

Well, if you want an example, I have about about a dozen PM and CO₂ sensors spread around the apartment, and some outside of it. I live in an extremely polluted area and it allows me to make decisions on when it's (relatively) safe to open windows (or even inside doors if it's really bad outside).

PM 2.5 may be in the range of a couple micrograms/m³ in one room (with air purification) and 100× that in the other adjacent room, so it makes sense to have sensors everywhere.

Still very far from 50, though.