Jefferson, Kentucky Air Quality
Jefferson County, Kentucky (KY)
→ Stableover 10 years
10-Year AQI Trend
The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days).
Air Quality Day Breakdown
Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).
Year-by-Year Data
| Year | Median AQI | 90th Pct | Max AQI | Good Days | Moderate | Unhealthy+ | Pollutant |
|---|---|---|---|---|---|---|---|
| 2023 | 55 | 81 | 171 | 123 | 226 | 16 | PM2.5 |
| 2022 | 53 | 71 | 136 | 147 | 211 | 7 | PM2.5 |
| 2021 | 54 | 74 | 126 | 138 | 221 | 6 | PM2.5 |
| 2020 | 52 | 64 | 115 | 151 | 208 | 7 | PM2.5 |
| 2019 | 54 | 71 | 136 | 124 | 239 | 2 | PM2.5 |
| 2018 | 54 | 77 | 166 | 125 | 232 | 8 | PM2.5 |
| 2017 | 54 | 67 | 112 | 133 | 228 | 4 | PM2.5 |
| 2016 | 54 | 80 | 151 | 121 | 230 | 15 | PM2.5 |
| 2015 | 55 | 74 | 174 | 113 | 243 | 9 | PM2.5 |
| 2014 | 58 | 80 | 169 | 90 | 271 | 4 | PM2.5 |
What This Means for Jefferson County Residents
Jefferson, Kentucky has received an Air Quality Grade of C (57/100) based on a decade of EPA monitoring data. The current median AQI of 55 falls in the "Moderate" range.
The primary pollutant affecting this area is Fine Particulate Matter (PM2.5). Over the past 5 years, this area has averaged 8 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity.