AQI Comparison
AQI 150 vs AQI 200
A one-step AQI category change can mean a meaningful increase in estimated PM2.5 concentration-time.
AQI 150
2.52
cigarette-equivalents per 24h
Unhealthy for Sensitive Groups: This is the point where many households should start changing plans.
AQI 200
5.7
cigarette-equivalents per 24h
Unhealthy: Everyone should start taking protective steps, not just sensitive groups.
What changes between these two AQI values
Difference in PM2.5
70
µg/m³
Difference per day
3.18
cigarettes
Direction
AQI 200 is materially heavier exposure
Moving from AQI 150 to AQI 200 changes both estimated PM2.5 concentration and the protection plan.
Calculate AQI 150
Open the interactive calculator with AQI 150 loaded.
Calculate AQI 200
Use the interactive calculator to test a different duration.
See how the numbers are derived
Review the AQI-to-PM2.5 and PM2.5-to-cigarettes methodology.