Airgradient's popular indoor air quality sensors are the first devices of their kind to be officially certified as "Works with Home Assistant". These open-source devices do not require an internet connection and enable local automation with air purifiers, air conditioners, or humidifiers and dehumidifiers.
I was a little skeptical and just looked at NFPA codes (USA) and they don’t seem to care about placement elevation, only type of rooms and heating sources. I didn’t read all 68 pages, only what seemed relevant, so maybe I missed some discussion.