Know the pollutant or proxy
CO2, particulate matter, humidity, VOC estimates and temperature are different measurements.
Trend can be more useful than one number
Changes over time can reveal patterns in occupancy or ventilation.
Consumer sensors have limits
They are not substitutes for regulatory instruments or medical diagnosis.
Automation should remain conservative
Use ventilation equipment and air cleaners according to their instructions rather than improvising unsafe control.
Keep in mind. Compatibility is not permanent. Confirm the current manufacturer, platform and certification information before purchasing, resetting or migrating a device.