# Counties in South Carolina by highest daily Air Quality Index (US EPA), 2007

All 25 values come from U.S. Environmental Protection Agency for 2007, so the places are comparable. 3 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/south-carolina-counties

| Rank | Place | index |
|---:|---|---:|
| 1 | Richland County | 217 |
| 2 | Pickens County | 169 |
| 3 | Charleston County | 162 |
| 4 | Abbeville County | 161 |
| 4 | Oconee County | 161 |
| 6 | Spartanburg County | 154 |
| 7 | Chester County | 151 |
| 8 | York County | 150 |
| 9 | Aiken County | 147 |
| 10 | Chesterfield County | 136 |
| 11 | Horry County | 129 |
| 11 | Union County | 129 |
| 13 | Williamsburg County | 122 |
| 14 | Barnwell County | 119 |
| 14 | Colleton County | 119 |
| 14 | Darlington County | 119 |
| 14 | Edgefield County | 119 |
| 18 | Florence County | 117 |
| 19 | Beaufort County | 115 |
| 20 | Cherokee County | 112 |
| 21 | Berkeley County | 105 |
| 22 | Greenville County | 101 |
| 23 | Lexington County | 99 |
| 24 | Georgetown County | 97 |
| 25 | Greenwood County | 93 |