Smoke: keep one room clean
Shut the windows and run an air purifier sized for the room.
Wildfire smoke guide →Air quality in District of Columbia, county by county
1 District of Columbia county has enough EPA monitor data to count bad-air days. Weighted by population, they averaged about 6 days a year from 2021 to 2025 when the air was unhealthy for sensitive groups or worse.
CDC's model, which estimates every county from monitors and satellites, gives the average District of Columbia county, weighted by population, almost no smoky days (fine particles over 35.4 µg/m³, mostly wildfire smoke) and about 2 high-ozone days a year at its worst spot (2018 to 2022). See every county on the map.
Every District of Columbia county with monitors
Most bad-air days first. 1 has a full report. Compare with the worst and the cleanest counties in the US.
| County | Bad-air days a year | |
|---|---|---|
| District of ColumbiaOzone | 6.4 | |
| No District of Columbia county with a monitor matches “”. Counties without a monitor aren't listed; a neighbor's numbers are a fair guide, or find it on the map. | ||
Counties without a monitor aren't listed. Air doesn't stop at the county line, so a neighbor's numbers are a fair guide.
What helps on a bad-air day
Check AirNow for today's reading and tomorrow's forecast, then match the step to the pollutant.
Upgrade the furnace filter
MERV 13 catches far more smoke than thin fiberglass filters.
Furnace filters →Questions people ask about air quality in District of Columbia
How often is the air bad in District of Columbia?
District of Columbia is the only part of District of Columbia with enough EPA monitor data. It averaged about 6 bad-air days a year from 2021 to 2025, days when the AQI was over 100.
Where can I check today's air quality in District of Columbia?
AirNow, run by the EPA and its partners, shows current readings and forecasts by ZIP code, and its fire and smoke map adds smoke plumes and low-cost sensors.
Sources: EPA AirData county AQI summaries, 2021 to 2025; CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone, 2018 to 2022. Updated November 8, 2026.