Bad Air Days in Davidson County, Tennessee: 3 a Year
3 bad air days a year
About the middle of monitored US counties. Ranked 367 of 996 monitored counties, where 1 is worst.
What makes them bad: mostly ozone: summer smog (26% particle days).
The bad-air season here
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Most bad days here fall in June and July and August. Averaged over 2016 to 2025.
Is a purifier worth it here?
- Bad air days are rare here. A standard furnace filter is enough; no purifier needed for outdoor air.
- On the odd bad day, check AirNow and keep windows shut.
Better or worse than it was
In 2000 to 2009 this county averaged 19 bad days a year; in 2016 to 2025, 3. The air has improved. The worst recent year was 2024, with 6 bad days on 366 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2018-06-08 | 151 | Ozone |
| 2022-07-22 | 143 | Ozone |
| 2025-06-11 | 136 | Ozone |
| 2017-07-21 | 133 | Ozone |
| 2023-06-28 | 133 | Ozone |
The air on a normal day
Across 3,653 monitored days from 2016 to 2025, the air in Davidson County rated Good on 45% of them, less often than the 72% typical of monitored counties, and Moderate on 54%. The median day sat at AQI 51; one day in ten went above 65.
The pollutant setting the AQI on an ordinary day here:
- fine particles (PM2.5)78%2,836 days
- ozone21%749 days
- nitrogen dioxide2%67 days
Year by year
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 365 | 193 | 171 | 1 | 0 | 49 | 136 |
| 2024 | 366 | 189 | 171 | 6 | 0 | 50 | 122 |
| 2023 | 365 | 136 | 225 | 4 | 0 | 53 | 133 |
| 2022 | 365 | 169 | 194 | 2 | 0 | 51 | 143 |
| 2021 | 365 | 152 | 209 | 4 | 0 | 52 | 116 |
| 2020 | 366 | 190 | 174 | 2 | 0 | 50 | 116 |
| 2019 | 365 | 151 | 213 | 1 | 0 | 52 | 101 |
| 2018 | 365 | 164 | 196 | 5 | 1 | 52 | 151 |
| 2017 | 365 | 161 | 203 | 1 | 0 | 53 | 133 |
| 2016 | 366 | 148 | 213 | 5 | 0 | 53 | 126 |
| 2015 | 365 | 141 | 224 | 0 | 0 | 53 | 97 |
| 2014 | 365 | 128 | 233 | 4 | 0 | 54 | 108 |
| 2013 | 365 | 144 | 220 | 1 | 0 | 53 | 101 |
| 2012 | 366 | 120 | 228 | 18 | 2 | 54 | 169 |
| 2011 | 365 | 128 | 233 | 4 | 0 | 54 | 150 |
| 2010 | 365 | 94 | 265 | 6 | 0 | 56 | 133 |
*2025 may be a partial year in EPA's file.
Tennessee compared
- Shelby County6/yr
- Blount County2/yr
- Sumner County2/yr
- Knox County2/yr
- Hamilton County2/yr
- Sevier County1/yr
- Loudon County1/yr
- Wilson County1/yr
How this is counted
A bad air day is a day the county's daily AQI from EPA AirData went above 100, the level where EPA tells children, older adults and people with asthma or heart disease to cut back outdoors. Monitors do not run every day, so yearly counts are scaled to 365 days. This is the record, not today's air: for that, check AirNow. More on the method in how the county numbers are made, on the AQI 100 line in what counts as a bad air day, and on why a purifier does not touch ozone in smoke vs ozone.