RANKABLE EPA COUNTY AQI
Air Quality in ZIP 21704 - Frederick, Maryland
County-derived EPA air-quality evidence connected locally through National Data System.
Median AQI
41.0
Maximum AQI
93.0
Good-air-quality days
85.65%
Average PM2.5
N/A
NDS Air Quality Score
59.83
U.S. County Rank
408 of 1,049
Percentile
61.07
Grade
C
What the data means
ZIP 21704 is connected to governed EPA county-level air-quality evidence for Frederick.
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.