I'm using the ecowitt WH41B (outdoors), WH45 (indoors), and a awair unit (indoors) to try and get a comprehensive view of PM2.5 on my property. I live with someone who is very sensitive to smoke, and so I'm trying to get solid charts and graphs to show whether we are a good job of filtering it inside.
I'm really interested in what others have done for calibration. The awair claims to be calibrated out of the box, but the WH41B and WH45 seem to suggest you calibrate it from the nearest legit sensor outside.
Should I pack them all up with a battery backup and drive to the nearest government sensor? It wouldn't be that hard. But outside of smoke season, normally PM2.5 values are so low that it feels like the offset would be really low.
Separately, I have the same question for my various humidity sensors, which appear to vary about 10% in the same room. Anybody have good strategies for finding the right offset?
Many thanks.