Bad Air Days in Teller County, Colorado
Not enough data
EPA monitors in Teller County ran on too few days between 2016 and 2025 to give a fair yearly count (about 44% of days covered). Neighbouring counties below are a better guide.
What to buy, and what not to
- EPA monitors here ran too few days to give a fair yearly count. Use AirNow for today's air.
The record for Teller
The worst recent year was 2018, with 12 bad days on 160 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2018-08-02 | 133 | Ozone |
| 2018-07-14 | 126 | Ozone |
| 2018-07-10 | 122 | Ozone |
| 2018-06-12 | 119 | Ozone |
| 2018-07-06 | 108 | Ozone |
An ordinary day in Teller
Across 160 monitored days from 2018 to 2018, the air in Teller County rated Good on 39% of them, less often than the 72% typical of monitored counties, and Moderate on 53%. The median day sat at AQI 58; one day in ten went above 97.
The pollutant setting the AQI on an ordinary day here:
- ozone100%160 days
Teller County by year
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2018 | 160 | 63 | 85 | 12 | 0 | 58 | 133 |
| 2010 | 130 | 63 | 65 | 2 | 0 | 51 | 105 |
Colorado compared
- Jefferson County28/yr
- Douglas County20/yr
- Larimer County18/yr
- Boulder County13/yr
- Weld County12/yr
- Arapahoe County12/yr
- Denver County12/yr
- Clear Creek County11/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.