Median AQI
39
Good
Ohio · County air quality · 2025
Wood County, Ohio
Median AQI 39 (Good). 85.3% of monitored days rated Good, direct from EPA Air Quality System stations.
- 39
- Median AQI
- 85.3%
- Good-air days
- 0
- Unhealthy days
- 66%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Wood County's air is good on balance, cleaner than the median US county, a median AQI of 39 with 85.3% of 244 monitored days in the Good band, driven mainly by Ozone.
- 39
- median AQI · Good
- 85.3%
- days rated Good
- Ozone
- main pollutant
- 66%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 108.
Data updated July 2026
- Good · 208 d · 85.2%
- Moderate · 35 d · 14.3%
- USG · 1 d · 0.4%
How did Wood County's air break down in 2025?
Across 244 monitored days, 208 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 108 (USG).
EPA AQS →Air quality data from EPA Air Quality System (2025). 244 days monitored. Median AQI: 39 (Good).
Insights: Wood County, Ohio. EPA monitors recorded a median Air Quality Index of 39 across 244 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 208 (85%) fell in the Good band (AQI 0–50), 35 (14%) registered Moderate readings, and 1 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 58, while the worst single-day peak hit 108 (USG). Residents averaged about 25.6 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (244 days). Across the 2020–2025 trend window, good days shifted by -8 and the median AQI moved +5 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 108, usg but never Unhealthy. Nearby counties show comparable readings: Allen (65.9% good, AQI 43); Ashtabula (81.2% good, AQI 43); Athens (80.3% good, AQI 33); Belmont (63.0% good, AQI 42); Butler (33.3% good, AQI 55); Clark (59.4% good, AQI 46).
Air Quality Summary
Good Days
85.3%
208 of 244 monitored days
10.3pp vs 75% target
Max AQI Recorded
108
USG
Health Grade
Good
90th-pct AQI 58
Wood County, Good days share 85.3%
National avg
Share of monitored days at AQI 0-50 (Good band).
Wood 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 244 monitored days across EPA AQI categories.
Good
208
85%
Moderate
35
14%
USG
1
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 Wood County.
- Ozone · 244 days · 100.0%
Health Impact Assessment
Good
Wood County's air quality is rated Good based on 85.3% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 85.3% 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 244 of 244 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Wood County. Best year: 2022 (220 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 216 | 13 | 0 | 0 | 34 | 80 |
| 2021 | 216 | 29 | 0 | 0 | 39 | 90 |
| 2022 | 220 | 22 | 0 | 0 | 38 | 97 |
| 2023 | 198 | 39 | 4 | 0 | 40 | 126 |
| 2024 | 203 | 41 | 1 | 0 | 41 | 101 |
| 2025 | 208 | 35 | 1 | 0 | 39 | 108 |
How does Wood County compare?
How Wood County compares
Good-day share better than US avg
Wood County 85.3%
Allen County, Ohio 65.9%
US average 76.5%
Median AQI worse than US avg
Wood County 39
Allen County, Ohio 43
US average 38
Unhealthy days / yr about average
Wood County 0
Allen County, Ohio 0
US average 0
Other Counties in Ohio
Air quality comparison for nearby counties in Ohio.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Wood 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
Bennington County, Vermont
AQI 39 · 82.9% good
What Wood 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 Wood County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Wood County with its Ohio neighbours before drawing a conclusion about the region. All of Ohio
Based on 244 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 Wood County, Ohio? ▼
Wood County has a median Air Quality Index (AQI) of 39, rated "Good." 85.3% of monitored days (208 out of 244) had good air quality in 2025.
What is the main pollutant in Wood County? ▼
The primary pollutant in Wood County is Ozone (O3), which was the main AQI driver on 244 days (100% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Wood County have? ▼
In 2025, Wood County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 108.
Is the air quality in Wood County getting better or worse? ▼
Air quality in Wood County is worsening based on 5-year trends (2020-2025). Best year: 2022 with 220 good days. Worst year: 2023 with 198 good days.
What does AQI 39 mean for health? ▼
Wood 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 Wood County compare to other counties in Ohio? ▼
Wood County has 85.3% good air days. Nearby counties in Ohio: Allen (65.9% good), Ashtabula (81.2% good), Athens (80.3% good), Belmont (63.0% good), Butler (33.3% good), Clark (59.4% good).
What is the 90th percentile AQI in Wood County? ▼
The 90th percentile AQI for Wood County is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 108 (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.