# Counties in North Carolina by highest daily Air Quality Index (US EPA), 2004

All 50 values come from U.S. Environmental Protection Agency for 2004, so the places are comparable. 12 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/north-carolina-counties

| Rank | Place | index |
|---:|---|---:|
| 1 | Mecklenburg County | 202 |
| 2 | Rowan County | 177 |
| 3 | Graham County | 150 |
| 3 | Randolph County | 150 |
| 3 | Wake County | 150 |
| 6 | Cumberland County | 147 |
| 6 | Granville County | 147 |
| 8 | Carteret County | 143 |
| 9 | Davie County | 136 |
| 9 | Durham County | 136 |
| 9 | Forsyth County | 136 |
| 9 | Montgomery County | 136 |
| 13 | Buncombe County | 133 |
| 13 | Haywood County | 133 |
| 13 | Union County | 133 |
| 16 | Caswell County | 129 |
| 16 | Franklin County | 129 |
| 16 | Person County | 129 |
| 16 | Pitt County | 129 |
| 20 | Camden County | 126 |
| 20 | Lenoir County | 126 |
| 20 | Martin County | 126 |
| 20 | Rockingham County | 126 |
| 24 | Davidson County | 125 |
| 25 | Alexander County | 122 |
| 25 | Edgecombe County | 122 |
| 25 | Guilford County | 122 |
| 25 | Johnston County | 122 |
| 25 | New Hanover County | 122 |
| 30 | Lincoln County | 119 |
| 31 | Jackson County | 115 |
| 32 | Catawba County | 114 |
| 33 | Avery County | 112 |
| 33 | Caldwell County | 112 |
| 33 | Chatham County | 112 |
| 36 | Robeson County | 111 |
| 36 | Wayne County | 111 |
| 38 | Alamance County | 110 |
| 39 | Yancey County | 108 |
| 40 | Cabarrus County | 105 |
| 40 | Macon County | 105 |
| 42 | Orange County | 104 |
| 43 | McDowell County | 103 |
| 44 | Swain County | 100 |
| 45 | Duplin County | 99 |
| 46 | Gaston County | 97 |
| 47 | Mitchell County | 95 |
| 48 | Watauga County | 94 |
| 49 | Onslow County | 84 |
| 50 | Henderson County | 34 |