Bad Air Days in Caswell County, North Carolina: 0 a Year
0 bad air days a year
Rare: among the cleanest-air counties EPA monitors. Ranked 970 of 996 monitored counties, where 1 is worst.
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.
The record for Caswell
In 2000 to 2009 this county averaged 26 bad days a year; in 2016 to 2025, 0. The air has improved.
| Date | AQI | Main pollutant |
|---|---|---|
| 2016-05-26 | 97 | Ozone |
| 2018-05-02 | 97 | Ozone |
| 2023-04-20 | 97 | Ozone |
| 2016-04-19 | 93 | Ozone |
| 2016-05-25 | 93 | Ozone |
Most days, not the worst ones
Across 2,804 monitored days from 2016 to 2025, the air in Caswell County rated Good on 94% of them, more often than the 72% typical of monitored counties, and Moderate on 6%. The median day sat at AQI 36; one day in ten went above 48.
The pollutant setting the AQI on an ordinary day here:
- ozone85%2,381 days
- coarse dust (PM10)15%419 days
Year by year
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 245 | 233 | 12 | 0 | 0 | 37 | 77 |
| 2024 | 244 | 225 | 19 | 0 | 0 | 38 | 84 |
| 2023 | 350 | 325 | 25 | 0 | 0 | 36 | 97 |
| 2022 | 264 | 253 | 11 | 0 | 0 | 39 | 64 |
| 2021 | 250 | 240 | 10 | 0 | 0 | 38 | 80 |
| 2020 | 354 | 349 | 5 | 0 | 0 | 31 | 61 |
| 2019 | 245 | 236 | 9 | 0 | 0 | 39 | 64 |
| 2018 | 232 | 198 | 34 | 0 | 0 | 40 | 97 |
| 2017 | 291 | 275 | 16 | 0 | 0 | 37 | 71 |
| 2016 | 329 | 303 | 26 | 0 | 0 | 33 | 97 |
| 2015 | 358 | 212 | 146 | 0 | 0 | 47 | 87 |
| 2014 | 357 | 155 | 202 | 0 | 0 | 52 | 97 |
| 2013 | 364 | 171 | 192 | 1 | 0 | 51 | 112 |
| 2012 | 353 | 162 | 187 | 4 | 0 | 52 | 136 |
| 2011 | 363 | 182 | 178 | 3 | 0 | 50 | 129 |
| 2010 | 365 | 176 | 183 | 6 | 0 | 51 | 126 |
*2025 may be a partial year in EPA's file.
Elsewhere in North Carolina
- Mecklenburg County4/yr
- Jackson Countythin data
- Forsyth County2/yr
- Union County2/yr
- Swain County2/yr
- Haywood County2/yr
- Graham County1/yr
- Guilford 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.