Median AQI
44
Good
Nebraska · County air quality · 2025
Douglas County, Nebraska
Median AQI 44 (Good). 66.8% of monitored days rated Good, direct from EPA Air Quality System stations.
- 44
- Median AQI
- 66.8%
- Good-air days
- 0
- Unhealthy days
- 26%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Douglas County's air is good on balance, more polluted than the median US county, a median AQI of 44 with 66.8% of 274 monitored days in the Good band, driven mainly by Ozone.
- 44
- median AQI · Good
- 66.8%
- days rated Good
- Ozone
- main pollutant
- 26%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 137.
Data updated July 2026
- Good · 183 d · 66.8%
- Moderate · 89 d · 32.5%
- USG · 2 d · 0.7%
How did Douglas County's air break down in 2025?
Across 274 monitored days, 183 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 137 (USG).
EPA AQS →Air quality data from EPA Air Quality System (2025). 274 days monitored. Median AQI: 44 (Good).
Insights: Douglas County, Nebraska. EPA monitors recorded a median Air Quality Index of 44 across 274 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 183 (67%) fell in the Good band (AQI 0–50), 89 (32%) registered Moderate readings, and 2 (1%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 64, while the worst single-day peak hit 137 (USG). Residents averaged about 20.0 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (141 days), PM2.5 (124 days), PM10 (8 days), CO (1 days). Across the 2020–2025 trend window, good days shifted by -84 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 137, usg but never Unhealthy. Nearby counties show comparable readings: Cass (96.5% good, AQI 20); Gage (74.0% good, AQI 36); Hall (80.2% good, AQI 37); Knox (89.3% good, AQI 39); Lancaster (77.7% good, AQI 36); Sarpy (77.1% good, AQI 33).
Air Quality Summary
Good Days
66.8%
183 of 274 monitored days
-8.2pp vs 75% target
Max AQI Recorded
137
USG
Health Grade
Moderate
90th-pct AQI 64
Douglas County, Good days share 66.8%
National avg
Share of monitored days at AQI 0-50 (Good band).
Douglas 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 274 monitored days across EPA AQI categories.
Good
183
67%
Moderate
89
32%
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 Douglas County.
- Ozone · 141 days · 51.5%
- PM2.5 · 124 days · 45.3%
- PM10 · 8 days · 2.9%
- CO · 1 days · 0.4%
Health Impact Assessment
Moderate
Douglas County's air quality is rated Moderate based on 66.8% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 66.8% of monitored days in 2025, with a median AQI of 44. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 141 of 274 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Douglas County. Best year: 2022 (278 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 267 | 97 | 1 | 1 | 42 | 157 |
| 2021 | 244 | 116 | 5 | 0 | 43 | 150 |
| 2022 | 278 | 86 | 1 | 0 | 41 | 108 |
| 2023 | 211 | 130 | 22 | 2 | 45 | 169 |
| 2024 | 233 | 132 | 1 | 0 | 45 | 101 |
| 2025 | 183 | 89 | 2 | 0 | 44 | 137 |
How does Douglas County compare?
How Douglas County compares
Good-day share worse than US avg
Douglas County 66.8%
Cass County, Nebraska 96.5%
US average 76.5%
Median AQI worse than US avg
Douglas County 44
Cass County, Nebraska 20
US average 38
Unhealthy days / yr about average
Douglas County 0
Cass County, Nebraska 0
US average 0
Other Counties in Nebraska
Air quality comparison for nearby counties in Nebraska.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Douglas County.
Baltimore County, Maryland
AQI 44 · 70.4% good
Baltimore (City) County, Maryland
AQI 44 · 68.7% good
Bartholomew County, Indiana
AQI 44 · 69.2% good
Berks County, Pennsylvania
AQI 44 · 65.6% good
Bolivar County, Mississippi
AQI 44 · 70.3% good
Brewster County, Texas
AQI 44 · 69.0% good
What Douglas 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 44 means for exposure. Health guidance
- See how Douglas County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Douglas County with its Nebraska neighbours before drawing a conclusion about the region. All of Nebraska
Based on 274 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 Douglas County, Nebraska? ▼
Douglas County has a median Air Quality Index (AQI) of 44, rated "Good." 66.8% of monitored days (183 out of 274) had good air quality in 2025.
What is the main pollutant in Douglas County? ▼
The primary pollutant in Douglas County is Ozone (O3), which was the main AQI driver on 141 days (51% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Douglas County have? ▼
In 2025, Douglas County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 137.
Is the air quality in Douglas County getting better or worse? ▼
Air quality in Douglas County is worsening based on 5-year trends (2020-2025). Best year: 2022 with 278 good days. Worst year: 2025 with 183 good days.
What does AQI 44 mean for health? ▼
Douglas County's median AQI of 44 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 Douglas County compare to other counties in Nebraska? ▼
Douglas County has 66.8% good air days. Nearby counties in Nebraska: Cass (96.5% good), Gage (74.0% good), Hall (80.2% good), Knox (89.3% good), Lancaster (77.7% good), Sarpy (77.1% good).
What is the 90th percentile AQI in Douglas County? ▼
The 90th percentile AQI for Douglas County is 64, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 137 (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.