RANKABLE EPA COUNTY AQI
Air Quality in ZIP 94574 - Saint Helena, California
County-derived EPA air-quality evidence connected locally through National Data System.
Median AQI
41.0
Maximum AQI
77.0
Good-air-quality days
77.14%
Average PM2.5
5.920 ug/m3
NDS Air Quality Score
60.40
U.S. County Rank
394 of 1,049
Percentile
62.40
Grade
C
What the data means
ZIP 94574 is connected to governed EPA county-level air-quality evidence for Napa.
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.