Median AQI
35
Good
Pennsylvania · County air quality · 2025
Bucks County, Pennsylvania
Median AQI 35 (Good). 87.5% of monitored days rated Good, direct from EPA Air Quality System stations.
- 35
- Median AQI
- 87.5%
- Good-air days
- 0
- Unhealthy days
- 70%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Bucks County's air is good on balance, cleaner than the median US county, a median AQI of 35 with 87.5% of 208 monitored days in the Good band, driven mainly by Ozone.
- 35
- median AQI · Good
- 87.5%
- days rated Good
- Ozone
- main pollutant
- 70%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 133.
Data updated July 2026
- Good · 182 d · 87.5%
- Moderate · 24 d · 11.5%
- USG · 2 d · 1.0%
How did Bucks County's air break down in 2025?
Across 208 monitored days, 182 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 133 (USG).
EPA AQS →Air quality data from EPA Air Quality System (2025). 208 days monitored. Median AQI: 35 (Good).
Insights: Bucks County, Pennsylvania. EPA monitors recorded a median Air Quality Index of 35 across 208 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 182 (88%) fell in the Good band (AQI 0–50), 24 (12%) registered Moderate readings, and 2 (1%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 58, while the worst single-day peak hit 133 (USG). Residents averaged about 26.3 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (167 days), NO2 (41 days). Across the 2020–2025 trend window, good days shifted by -149 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 133, usg but never Unhealthy. Nearby counties show comparable readings: Adams (73.8% good, AQI 42); Allegheny (51.6% good, AQI 49); Armstrong (68.1% good, AQI 42); Beaver (54.3% good, AQI 47); Berks (65.6% good, AQI 44); Blair (71.9% good, AQI 41).
Air Quality Summary
Good Days
87.5%
182 of 208 monitored days
12.5pp vs 75% target
Max AQI Recorded
133
USG
Health Grade
Good
90th-pct AQI 58
Bucks County, Good days share 87.5%
National avg
Share of monitored days at AQI 0-50 (Good band).
Bucks 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 208 monitored days across EPA AQI categories.
Good
182
88%
Moderate
24
12%
USG
2
1%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Bucks County.
- Ozone · 167 days · 80.3%
- NO₂ · 41 days · 19.7%
Health Impact Assessment
Good
Bucks County's air quality is rated Good based on 87.5% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 87.5% of monitored days in 2025, with a median AQI of 35. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 167 of 208 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Bucks County. Best year: 2020 (331 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 331 | 16 | 4 | 0 | 33 | 115 |
| 2021 | 239 | 34 | 10 | 0 | 37 | 143 |
| 2022 | 196 | 39 | 2 | 0 | 41 | 119 |
| 2023 | 241 | 50 | 4 | 1 | 39 | 200 |
| 2024 | 293 | 53 | 10 | 0 | 36 | 150 |
| 2025 | 182 | 24 | 2 | 0 | 35 | 133 |
How does Bucks County compare?
How Bucks County compares
Good-day share better than US avg
Bucks County 87.5%
Adams County, Pennsylvania 73.8%
US average 76.5%
Median AQI better than US avg
Bucks County 35
Adams County, Pennsylvania 42
US average 38
Unhealthy days / yr about average
Bucks County 0
Adams County, Pennsylvania 0
US average 0
Other Counties in Pennsylvania
Air quality comparison for nearby counties in Pennsylvania.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Bucks County.
Androscoggin County, Maine
AQI 35 · 85.5% good
Asotin County, Washington
AQI 35 · 73.8% good
Benton County, Washington
AQI 35 · 88.9% good
Benzie County, Michigan
AQI 35 · 91.1% good
Brooke County, West Virginia
AQI 35 · 79.3% good
Carlton County, Minnesota
AQI 35 · 92.9% good
What Bucks 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 35 means for exposure. Health guidance
- See how Bucks County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Bucks County with its Pennsylvania neighbours before drawing a conclusion about the region. All of Pennsylvania
Based on 208 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 Bucks County, Pennsylvania? ▼
Bucks County has a median Air Quality Index (AQI) of 35, rated "Good." 87.5% of monitored days (182 out of 208) had good air quality in 2025.
What is the main pollutant in Bucks County? ▼
The primary pollutant in Bucks County is Ozone (O3), which was the main AQI driver on 167 days (80% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Bucks County have? ▼
In 2025, Bucks County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 133.
Is the air quality in Bucks County getting better or worse? ▼
Air quality in Bucks County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 331 good days. Worst year: 2025 with 182 good days.
What does AQI 35 mean for health? ▼
Bucks County's median AQI of 35 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 Bucks County compare to other counties in Pennsylvania? ▼
Bucks County has 87.5% good air days. Nearby counties in Pennsylvania: Adams (73.8% good), Allegheny (51.6% good), Armstrong (68.1% good), Beaver (54.3% good), Berks (65.6% good), Blair (71.9% good).
What is the 90th percentile AQI in Bucks County? ▼
The 90th percentile AQI for Bucks County is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 133 (USG).
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.