# Counties in Tennessee by median Air Quality Index (US EPA), 2003

All 30 values come from U.S. Environmental Protection Agency for 2003, so the places are comparable. 12 counties have no value for that period and are not ranked.

- Indicator id: `aqi_median`
- Unit: index
- Definition: Median of the daily Air Quality Index (AQI) values of a US county over the days of the year with an AQI, from the EPA AirData annual summaries. The daily county AQI is the highest AQI among the monitors and pollutants reported that day (ozone, PM2.5, PM10, carbon monoxide and nitrogen dioxide). Lower is cleaner: 0 to 50 is good, 51 to 100 moderate and above 100 unhealthy for sensitive groups.
- Source: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: median 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: median daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
- Web page: https://invokely.ai/rankings/median-air-quality-index/tennessee-counties

| Rank | Place | index |
|---:|---|---:|
| 1 | Shelby County | 65 |
| 2 | Knox County | 62 |
| 3 | Davidson County | 61 |
| 3 | Loudon County | 61 |
| 5 | Roane County | 57 |
| 6 | Dyer County | 55 |
| 6 | Hamilton County | 55 |
| 6 | Maury County | 55 |
| 9 | Putnam County | 54 |
| 9 | Sumner County | 54 |
| 11 | Montgomery County | 53 |
| 12 | Blount County | 51 |
| 13 | Lawrence County | 49 |
| 13 | Sevier County | 49 |
| 15 | Williamson County | 48 |
| 16 | Rutherford County | 46 |
| 16 | Sullivan County | 46 |
| 16 | Wilson County | 46 |
| 19 | Haywood County | 44 |
| 19 | Jefferson County | 44 |
| 19 | Meigs County | 44 |
| 22 | Obion County | 43 |
| 23 | Anderson County | 42 |
| 24 | DeKalb County | 38 |
| 24 | Humphreys County | 38 |
| 26 | Claiborne County | 37 |
| 27 | Union County | 31 |
| 28 | Madison County | 28 |
| 29 | McMinn County | 24 |
| 30 | Bradley County | 22 |