EPA AirData
2023-2025 annual summaries; files refreshed June 25, 2026- Data
- EPA annual AQI by county and annual concentration by monitor files for PM2.5 and ozone, using observed exceptional-event conditions and EPA's corrected PM2.5 monitor-method guidance.
- What it tells us
- Provides a recent three-year county-level outdoor-air profile. Missing county metrics use state or national fallback evidence that is explicitly pulled toward neutral; this is not a neighborhood or indoor-exposure model.