Use an indoor air quality monitor that measures PM2.5, PM10, CO2, VOCs, temperature, and humidity
Check the monitor’s AQI reading if it provides one
Compare PM2.5 levels to AQI standards using a reliable AQI chart or app
Use a smartphone-connected air quality sensor for real-time room readings
Check your HVAC or air purifier display if it has air quality indicators
Look for signs of poor air quality such as stuffiness, odors, or excessive dust
Use a CO2 monitor to assess ventilation quality
Place the sensor in the center of the room away from windows, vents, and direct airflow
Take readings at different times of day for a more accurate picture
Verify the device is calibrated or recently calibrated for accurate results