Median AQI
49
Good
Oklahoma · County air quality · 2025
Ottawa County, Oklahoma
Median AQI 49 (Good). 53.1% of monitored days rated Good, direct from EPA Air Quality System stations.
- 49
- Median AQI
- 53.1%
- Good-air days
- 1
- Unhealthy days
- 9%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Ottawa County's air is good on balance, among the most polluted counties nationally, a median AQI of 49 with 53.1% of 273 monitored days in the Good band, driven mainly by PM2.5.
- 49
- median AQI · Good
- 53.1%
- days rated Good
- PM2.5
- main pollutant
- 9%
- cleaner than US counties
1 day reached Unhealthy or worse; the worst single reading hit AQI 305.
Data updated July 2026
- Good · 145 d · 53.1%
- Moderate · 126 d · 46.2%
- USG · 1 d · 0.4%
- Hazardous · 1 d · 0.4%
How did Ottawa County's air break down in 2025?
Across 273 monitored days, 145 fell in the Good band (AQI 0–50) and 1 reached Unhealthy or worse. The worst single day peaked at AQI 305 (Hazardous).
EPA AQS →Air quality data from EPA Air Quality System (2025). 273 days monitored. Median AQI: 49 (Good).
Insights: Ottawa County, Oklahoma. EPA monitors recorded a median Air Quality Index of 49 across 273 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 145 (53%) fell in the Good band (AQI 0–50), 126 (46%) registered Moderate readings, and 1 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 66, while the worst single-day peak hit 305 (Hazardous). Residents averaged about 15.9 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (192 days), Ozone (71 days), PM10 (10 days). Across the 2020–2025 trend window, good days shifted by -57 and the median AQI moved +3 points, placing the multi-year trajectory at worsening. Residents and visitors experienced 1 unhealthy-or-worse days combined, periods when the EPA recommends sensitive groups limit prolonged outdoor exertion. Nearby counties show comparable readings: Adair (59.2% good, AQI 45); Canadian (78.0% good, AQI 44); Carter (80.9% good, AQI 33); Cleveland (53.7% good, AQI 49); Comanche (63.8% good, AQI 45); Creek (80.1% good, AQI 43).
Air Quality Summary
Good Days
53.1%
145 of 273 monitored days
-21.9pp vs 75% target
Max AQI Recorded
305
Hazardous
Health Grade
Moderate
90th-pct AQI 66
Ottawa County, Good days share 53.1%
National avg
Share of monitored days at AQI 0-50 (Good band).
Ottawa County, Unhealthy-or-worse share 0.4%
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 273 monitored days across EPA AQI categories.
Good
145
53%
Moderate
126
46%
USG
1
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
1
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Ottawa County.
- PM2.5 · 192 days · 70.3%
- Ozone · 71 days · 26.0%
- PM10 · 10 days · 3.7%
Health Impact Assessment
Moderate
Ottawa County's air quality is rated Moderate based on 53.1% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.
Air quality posed significant health risk in 2025. Sensitive groups, including people with asthma, COPD, cardiovascular conditions, children, pregnant women, and adults over 65, should monitor AirNow.gov alerts and limit outdoor activity on Unhealthy (AQI 151+) and Very Unhealthy (201+) days. Peak readings reached AQI 305, well into the Hazardous range.
Sensitive group advisory
People with asthma, COPD, heart disease, children, pregnant women, and adults 65+ should follow EPA AQI alerts daily and limit outdoor exertion when AQI exceeds 100. Real-time conditions: airnow.gov.
The dominant pollutant is PM2.5, driving AQI on 192 of 273 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Ottawa County. Best year: 2020 (202 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 202 | 148 | 1 | 1 | 46 | 154 |
| 2021 | 90 | 258 | 14 | 3 | 59 | 169 |
| 2022 | 151 | 203 | 6 | 4 | 53 | 238 |
| 2023 | 141 | 215 | 7 | 1 | 54 | 162 |
| 2024 | 181 | 184 | 0 | 0 | 51 | 288 |
| 2025 | 145 | 126 | 1 | 0 | 49 | 305 |
How does Ottawa County compare?
How Ottawa County compares
Good-day share worse than US avg
Ottawa County 53.1%
Adair County, Oklahoma 59.2%
US average 76.5%
Median AQI worse than US avg
Ottawa County 49
Adair County, Oklahoma 45
US average 38
Unhealthy days / yr worse than US avg
Ottawa County 1
Adair County, Oklahoma 2
US average 0
Other Counties in Oklahoma
Air quality comparison for nearby counties in Oklahoma.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Ottawa County.
Allegheny County, Pennsylvania
AQI 49 · 51.6% good
Arkansas County, Arkansas
AQI 49 · 51.6% good
Ashley County, Arkansas
AQI 49 · 53.9% good
Clayton County, Georgia
AQI 49 · 53.1% good
Cleveland County, Oklahoma
AQI 49 · 53.7% good
Dewey County, Oklahoma
AQI 49 · 56.6% good
What Ottawa County's air means for you
On most days the air here is fine, but PM2.5 drives 1 unhealthy-or-worse day a year that sensitive groups should plan around.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 49 means for exposure. Health guidance
- See how Ottawa County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Ottawa County with its Oklahoma neighbours before drawing a conclusion about the region. All of Oklahoma
Based on 273 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 Ottawa County, Oklahoma? ▼
Ottawa County has a median Air Quality Index (AQI) of 49, rated "Good." 53.1% of monitored days (145 out of 273) had good air quality in 2025.
What is the main pollutant in Ottawa County? ▼
The primary pollutant in Ottawa County is Fine Particles (PM2.5), which was the main AQI driver on 192 days (70% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Ottawa County have? ▼
In 2025, Ottawa County recorded 1 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 1 Hazardous). The maximum AQI reached 305.
Is the air quality in Ottawa County getting better or worse? ▼
Air quality in Ottawa County is worsening based on 5-year trends (2020-2025). Best year: 2020 with 202 good days. Worst year: 2021 with 90 good days.
What does AQI 49 mean for health? ▼
Ottawa County's median AQI of 49 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 Ottawa County compare to other counties in Oklahoma? ▼
Ottawa County has 53.1% good air days. Nearby counties in Oklahoma: Adair (59.2% good), Canadian (78.0% good), Carter (80.9% good), Cleveland (53.7% good), Comanche (63.8% good), Creek (80.1% good).
What is the 90th percentile AQI in Ottawa County? ▼
The 90th percentile AQI for Ottawa County is 66, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 305 (Hazardous).
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.