Air quality · Vermont
Air quality in Vermont
The one Vermont ZIP with EPA county air-quality data has a Good median day (median AQI 38). 1 day across those counties reached Unhealthy or worse in 2025. This is a 2025 county annual summary, not a live reading.
Last verified 2026-09-24 · methodology
Air quality by ZIP code in Vermont
EPA's 2025 annual summary for each ZIP's county. Median AQI is the typical day; lower is cleaner.
| ZIP | Median AQI | Good days | Unhealthy or worse |
|---|---|---|---|
| 05401BurlingtonChittenden County | 38 Good | 320 of 365 | 1 |
| 05753Middlebury (VT)Addison County | No data | ||
| 05641Montpelier (VT)Washington County | No data |
County-level figures from EPA Air Quality System (AQS), annual county summary, joined to each ZIP by county. None of them is a measurement at a specific address.
What lands here
Pages show the 2025 median AQI category (Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, Hazardous) for the ZIP's county, plus the year's max/90th-percentile AQI and day-count breakdown by category.
Source & refresh
EPA Air Quality System (AQS), annual county summary. Refreshed annual (epa aqs publication). Primary source →
Vermont top concern
Radon Zone 1, river flooding
Vermont is uniformly Zone 1 radon. River flooding (Tropical Storm Irene 2011, July 2023 events) drives FEMA AE zone revisions. Older housing stock means lead-paint risk in Burlington, Rutland.
See Vermont state page for the full state-level rollup across all 12 dimensions.
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