Median AQI
39
Good
Vermont · County air quality · 2025
Bennington County, Vermont
Median AQI 39 (Good). 82.9% of monitored days rated Good, direct from EPA Air Quality System stations.
- 39
- Median AQI
- 82.9%
- Good-air days
- 0
- Unhealthy days
- 60%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Bennington County's air is good on balance, cleaner than the median US county, a median AQI of 39 with 82.9% of 181 monitored days in the Good band, driven mainly by Ozone.
- 39
- median AQI · Good
- 82.9%
- days rated Good
- Ozone
- main pollutant
- 60%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 93.
Data updated July 2026
- Good · 150 d · 82.9%
- Moderate · 31 d · 17.1%
How did Bennington County's air break down in 2025?
Across 181 monitored days, 150 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 93 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 181 days monitored. Median AQI: 39 (Good).
Insights: Bennington County, Vermont. EPA monitors recorded a median Air Quality Index of 39 across 181 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 150 (83%) fell in the Good band (AQI 0–50), 31 (17%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 54, while the worst single-day peak hit 93 (Moderate). Residents averaged about 24.9 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (147 days), PM2.5 (34 days). Across the 2020–2025 trend window, good days shifted by -180 and the median AQI moved +2 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 93, moderate but never Unhealthy. Nearby counties show comparable readings: Chittenden (91.2% good, AQI 40); Rutland (78.9% good, AQI 38); Windham (100.0% good, AQI 12).
Air Quality Summary
Good Days
82.9%
150 of 181 monitored days
7.9pp vs 75% target
Max AQI Recorded
93
Moderate
Health Grade
Good
90th-pct AQI 54
Bennington County, Good days share 82.9%
National avg
Share of monitored days at AQI 0-50 (Good band).
Bennington County, Unhealthy-or-worse share 0.0%
National avg
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
AQI Day Breakdown (2025)
Distribution of 181 monitored days across EPA AQI categories.
Good
150
83%
Moderate
31
17%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Bennington County.
- Ozone · 147 days · 81.2%
- PM2.5 · 34 days · 18.8%
Health Impact Assessment
Good
Bennington County's air quality is rated Good based on 82.9% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 82.9% of monitored days in 2025, with a median AQI of 39. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 147 of 181 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Bennington County. Best year: 2024 (332 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 330 | 36 | 0 | 0 | 37 | 73 |
| 2021 | 307 | 57 | 1 | 0 | 37 | 115 |
| 2022 | 324 | 41 | 0 | 0 | 37 | 74 |
| 2023 | 290 | 63 | 4 | 2 | 38 | 157 |
| 2024 | 332 | 33 | 0 | 0 | 36 | 80 |
| 2025 | 150 | 31 | 0 | 0 | 39 | 93 |
How does Bennington County compare?
How Bennington County compares
Good-day share better than US avg
Bennington County 82.9%
Chittenden County, Vermont 91.2%
US average 76.5%
Median AQI worse than US avg
Bennington County 39
Chittenden County, Vermont 40
US average 38
Unhealthy days / yr about average
Bennington County 0
Chittenden County, Vermont 0
US average 0
Other Counties in Vermont
Air quality comparison for nearby counties in Vermont.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Bennington County.
Ada County, Idaho
AQI 39 · 80.6% good
Aiken County, South Carolina
AQI 39 · 89.1% good
Albany County, New York
AQI 39 · 67.4% good
Alexander County, North Carolina
AQI 39 · 92.4% good
Ashland County, Wisconsin
AQI 39 · 85.6% good
Boyd County, Kentucky
AQI 39 · 82.8% good
What Bennington County's air means for you
The air here stays in the breathable range year-round, with Ozone the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-Ozone days, the guide explains what a median of 39 means for exposure. Health guidance
- See how Bennington County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Bennington County with its Vermont neighbours before drawing a conclusion about the region. All of Vermont
Based on 181 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.
More Air Quality Data
Air Quality Guides
Frequently Asked Questions
What is the air quality in Bennington County, Vermont? ▼
Bennington County has a median Air Quality Index (AQI) of 39, rated "Good." 82.9% of monitored days (150 out of 181) had good air quality in 2025.
What is the main pollutant in Bennington County? ▼
The primary pollutant in Bennington County is Ozone (O3), which was the main AQI driver on 147 days (81% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Bennington County have? ▼
In 2025, Bennington County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 93.
Is the air quality in Bennington County getting better or worse? ▼
Air quality in Bennington County is worsening based on 5-year trends (2020-2025). Best year: 2024 with 332 good days. Worst year: 2025 with 150 good days.
What does AQI 39 mean for health? ▼
Bennington County's median AQI of 39 falls in the "Good" category. See the <a href="/guides/understanding-aqi" class="underline">AQI category guide</a> for what each range means for health.
How does Bennington County compare to other counties in Vermont? ▼
Bennington County has 82.9% good air days. Nearby counties in Vermont: Chittenden (91.2% good), Rutland (78.9% good), Windham (100.0% good).
What is the 90th percentile AQI in Bennington County? ▼
The 90th percentile AQI for Bennington County is 54, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 93 (Moderate).
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer.
Every figure on PlainAir is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.