Air Quality in District Of Columbia
District Of Columbia earns an average Air Quality Grade of B, with a 5-year median AQI of 49 across 1 monitored area — 8 points above the national average of 41.
See full District Of Columbia air quality rankings →Understanding Air Quality in District Of Columbia
District Of Columbia earns an average Air Quality Grade of B, with a 5-year median AQI of 49 across 1 monitored area — 8 points above the national average of 41. The grade combines four signals — 5-year median AQI, 10-year trend direction, count of unhealthy days per year, and dominant pollutant — into a single A-F score. District Of Columbia's one monitored area collectively logged 30 days at "Unhealthy for Sensitive Groups" or worse over the last five years.
District Of Columbia is on a clear improving trajectory: 1 of 1 monitored areas are showing measurably cleaner air over the past decade, versus only 0 that are getting worse. That mirrors the broader national pattern of falling particulate and ozone pollution as cleaner vehicles, cleaner power generation, and tighter industrial standards take effect.
The dominant pollutant across 1 of 1 District Of Columbia area is Fine Particulate Matter (PM2.5). PM2.5 (fine particulate matter) is most often driven by combustion sources — vehicle exhaust, industrial emissions, residential wood burning, and increasingly wildfire smoke. It penetrates deep into lung tissue and the bloodstream and is the air pollutant most strongly linked to long-term health impacts.
District of Columbia, District Of Columbia is the fastest-improving area in District Of Columbia, with median AQI falling by 0.6 points per year over the EPA reporting period. Steady improvement at that pace usually reflects fleet turnover (older diesels retiring), upwind power-plant retirements, and tighter local emissions controls.
Grade Distribution Across District Of Columbia
Of 1 District Of Columbia monitored area, 0 earn a top grade (A or B), 1 sits in the middle (C), and 0 fall below average (D or F).
All Monitored Areas in District Of Columbia
Frequently Asked Questions
District Of Columbia has 1 monitored areas with a 5-year median AQI of 49 and an average Air Quality Grade of B. The dominant pollutant across the state is Fine Particulate Matter (PM2.5). 1 cities are improving, 0 are worsening, and 0 are stable.
District of Columbia, District Of Columbia has the best Air Quality Grade (C, score 63/100) in District Of Columbia with a 5-year median AQI of 49. Its dominant pollutant is Fine Particulate Matter (PM2.5), and the long-run trend is improving.
District Of Columbia has only 1 monitored area, so a "worst" ranking is not meaningful. See the city detail page for the full grade breakdown.
Of 1 monitored areas in District Of Columbia, 1 are showing improving trends, 0 are worsening, and 0 remain stable over the past decade. District of Columbia, District Of Columbia is the fastest-improving area in the state, with median AQI dropping by 0.6 points per year.
Fine Particulate Matter (PM2.5) is the dominant pollutant in 1 of 1 District Of Columbia monitored areas. PM2.5 (fine particulate matter) is most often driven by combustion sources — vehicle exhaust, industrial emissions, residential wood burning, and increasingly wildfire smoke. It penetrates deep into lung tissue and the bloodstream and is the air pollutant most strongly linked to long-term health impacts.
The this entity record above pulls directly from the EPA Air Quality System (AQS). What follows is the per-entity context — how this entity sits in the broader U.S. air quality and pollution monitoring distribution and which underlying factors drive the headline numbers.
The methodology behind every numeric value on this page is publicly documented on the the EPA Air Quality System (AQS) portal and described in detail on this site’s methodology page. Refresh cadence varies by underlying series; the page surfaces the as-of date for each number so readers can trace any figure back to the source release.
Practical use of this page is in combination with the comparison and ranking pages elsewhere on the site, which surface the same data for this entity’s peers within U.S. counties and states. A single-entity reading without peer context can be misleading when an entity is an outlier on one axis but typical on another.
Source: EPA Outdoor Air Quality Data, 2026.