RANKABLE EPA COUNTY AQI
Air Quality in ZIP 21757 - Keymar, Maryland
County-derived EPA air-quality evidence connected locally through National Data System.
Median AQI
38.0
Maximum AQI
90.0
Good-air-quality days
90.34%
Average PM2.5
N/A
NDS Air Quality Score
70.21
U.S. County Rank
245 of 1,049
Percentile
76.62
Grade
B
What the data means
ZIP 21757 is connected to governed EPA county-level air-quality evidence for Carroll.
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.