Air quality · Maryland
Air quality in Maryland
Air quality (EPA AirNow) data for ZIP codes in Maryland. Pick a ZIP below to dive into the air quality summary.
Last verified 2026-05-13 · methodology
What lands here
Pages show the current AQI category (Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, Hazardous), the nearest reporting station, and historical averages.
Source & refresh
EPA AirNow. Refreshed hourly real-time / daily historical. Primary source →
Maryland top concern
Chesapeake flood, lead pipes
Maryland has dense FEMA NFHL coverage along Chesapeake Bay tributaries. Baltimore City has extensive LCRR lead-service-line obligations and flagged EPA SDWIS compliance history. Radon Zone 1-2 across most counties.
See Maryland state page for the full state-level rollup across all 12 dimensions.
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