# Counties in Nebraska by highest daily Air Quality Index (US EPA), 2008

All 13 values come from U.S. Environmental Protection Agency for 2008, so the places are comparable. 11 counties have no value for that period and are not ranked.

- Indicator id: `aqi_max`
- Unit: index
- Definition: Highest daily Air Quality Index (AQI) value recorded in a US county during the year, from the EPA AirData annual summaries. Values above 500 are beyond the AQI scale and are published as EPA computes them.
- Source: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: highest daily AQI (https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual)
- Publisher page: https://invokely.ai/en/publishers/environmental-protection-agency
- Retrieved: 2026-10-12
- Citation: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
- Web page: https://invokely.ai/rankings/highest-daily-air-quality-index/nebraska-counties

| Rank | Place | index |
|---:|---|---:|
| 1 | Douglas County | 121 |
| 2 | Sioux County | 105 |
| 3 | Cass County | 94 |
| 4 | Scotts Bluff County | 92 |
| 5 | Sarpy County | 84 |
| 6 | Lancaster County | 83 |
| 7 | Thurston County | 77 |
| 8 | Knox County | 74 |
| 9 | Hall County | 69 |
| 10 | Washington County | 68 |
| 11 | Garden County | 62 |
| 12 | Dawson County | 58 |
| 13 | Thomas County | 52 |