Median AQI
35
Good
West Virginia · County air quality · 2025
Brooke County, West Virginia
Median AQI 35 (Good). 79.3% of monitored days rated Good, direct from EPA Air Quality System stations.
- 35
- Median AQI
- 79.3%
- Good-air days
- 0
- Unhealthy days
- 50%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Brooke County's air is good on balance, cleaner than the median US county, a median AQI of 35 with 79.3% of 159 monitored days in the Good band, driven mainly by PM2.5.
- 35
- median AQI · Good
- 79.3%
- days rated Good
- PM2.5
- main pollutant
- 50%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 75.
Data updated July 2026
- Good · 126 d · 79.2%
- Moderate · 33 d · 20.8%
How did Brooke County's air break down in 2025?
Across 159 monitored days, 126 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 75 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 159 days monitored. Median AQI: 35 (Good).
Insights: Brooke County, West Virginia. EPA monitors recorded a median Air Quality Index of 35 across 159 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 126 (79%) fell in the Good band (AQI 0–50), 33 (21%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 56, while the worst single-day peak hit 75 (Moderate). Residents averaged about 23.8 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (159 days). Across the 2020–2025 trend window, good days shifted by -192 and the median AQI moved +17 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 75, moderate but never Unhealthy. Nearby counties show comparable readings: Berkeley (81.1% good, AQI 40); Cabell (74.0% good, AQI 41); Greenbrier (89.3% good, AQI 42); Hancock (74.6% good, AQI 42); Harrison (73.3% good, AQI 32); Kanawha (79.6% good, AQI 40).
Air Quality Summary
Good Days
79.3%
126 of 159 monitored days
4.3pp vs 75% target
Max AQI Recorded
75
Moderate
Health Grade
Good
90th-pct AQI 56
Brooke County, Good days share 79.3%
National avg
Share of monitored days at AQI 0-50 (Good band).
Brooke 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 159 monitored days across EPA AQI categories.
Good
126
79%
Moderate
33
21%
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 Brooke County.
- PM2.5 · 159 days · 100.0%
Health Impact Assessment
Good
Brooke County's air quality is rated Good based on 79.3% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 79.3% 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 PM2.5, driving AQI on 159 of 159 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Brooke County. Best year: 2022 (321 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 318 | 48 | 0 | 0 | 18 | 78 |
| 2021 | 295 | 67 | 0 | 0 | 21 | 83 |
| 2022 | 321 | 42 | 0 | 0 | 18 | 76 |
| 2023 | 316 | 43 | 2 | 1 | 19 | 183 |
| 2024 | 277 | 89 | 0 | 0 | 36 | 72 |
| 2025 | 126 | 33 | 0 | 0 | 35 | 75 |
How does Brooke County compare?
How Brooke County compares
Good-day share better than US avg
Brooke County 79.3%
Berkeley County, West Virginia 81.1%
US average 76.5%
Median AQI better than US avg
Brooke County 35
Berkeley County, West Virginia 40
US average 38
Unhealthy days / yr about average
Brooke County 0
Berkeley County, West Virginia 0
US average 0
Other Counties in West Virginia
Air quality comparison for nearby counties in West Virginia.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Brooke 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
Bucks County, Pennsylvania
AQI 35 · 87.5% good
Carlton County, Minnesota
AQI 35 · 92.9% good
What Brooke County's air means for you
The air here stays in the breathable range year-round, with PM2.5 the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 35 means for exposure. Health guidance
- See how Brooke County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Brooke County with its West Virginia neighbours before drawing a conclusion about the region. All of West Virginia
Based on 159 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 Brooke County, West Virginia? ▼
Brooke County has a median Air Quality Index (AQI) of 35, rated "Good." 79.3% of monitored days (126 out of 159) had good air quality in 2025.
What is the main pollutant in Brooke County? ▼
The primary pollutant in Brooke County is Fine Particles (PM2.5), which was the main AQI driver on 159 days (100% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Brooke County have? ▼
In 2025, Brooke County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 75.
Is the air quality in Brooke County getting better or worse? ▼
Air quality in Brooke County is worsening based on 5-year trends (2020-2025). Best year: 2022 with 321 good days. Worst year: 2025 with 126 good days.
What does AQI 35 mean for health? ▼
Brooke 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 Brooke County compare to other counties in West Virginia? ▼
Brooke County has 79.3% good air days. Nearby counties in West Virginia: Berkeley (81.1% good), Cabell (74.0% good), Greenbrier (89.3% good), Hancock (74.6% good), Harrison (73.3% good), Kanawha (79.6% good).
What is the 90th percentile AQI in Brooke County? ▼
The 90th percentile AQI for Brooke County is 56, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 75 (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.