RANKABLE EPA COUNTY AQI
Air Quality in ZIP 20149 - Ashburn, Virginia
County-derived EPA air-quality evidence connected locally through National Data System.
Median AQI
43.0
Maximum AQI
120.0
Good-air-quality days
75.82%
Average PM2.5
7.189 ug/m3
NDS Air Quality Score
33.78
U.S. County Rank
785 of 1,049
Percentile
25.00
Grade
D
What the data means
ZIP 20149 is connected to governed EPA county-level air-quality evidence for Loudoun.
ZIP ranking note: ZIPs are not separately ranked. The rank shown on this page is the associated county rank because the EPA AQI evidence used here is county-derived.
County context
Methodology
EPA AQI evidence is county-derived. NDS connects that evidence to ZIP geography where a governed county relationship exists. NDS does not claim that EPA directly ranks ZIP codes.