Processed on 2024-03-04 12:51:23 PST.

Disclaimer: Data presented here come from a variety of sources and do not represent official EPA measurements. Please visit AirNow for official measurements.

Cumulative exposure to smoke is an important public health metric. This report summarizes the cumulative number of days air quality monitors in Colorado spent in each AQI category during the the month of January.

The tables below include only permanent monitors measuring PM2.5 and show cumulative exposure under existing NAAQS (National Ambient Air Quality Standards) and under the 2024 revised standards for PM2.5.

In the tables and plots below, ‘Old’ designates cumulative days calculated using the 2023 PM2.5 NAAQS while ‘New’ is calculated using the 2024 revised PM2.5 NAAQS. The impact of the NAAQS revision is quite clear.

January in Colorado

January 2014 – 19 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 261 52 0 0 0 0 28
New 238 75 0 0 0 0 28

January 2015 – 19 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 212 52 0 0 0 0 46
New 169 95 0 0 0 0 46

January 2016 – 30 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 175 106 2 0 0 0 58
New 119 161 3 0 0 0 58

January 2017 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 294 85 0 0 0 0 24
New 219 160 0 0 0 0 24

January 2018 – 41 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 328 66 1 0 0 0 8
New 264 130 1 0 0 0 8

January 2019 – 20 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 354 58 0 0 0 0 22
New 272 140 0 0 0 0 22

January 2020 – 39 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 376 22 1 0 0 0 35
New 324 74 1 0 0 0 35

January 2021 – 27 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 412 79 0 0 0 0 5
New 352 139 0 0 0 0 5

January 2022 – 34 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 406 83 1 0 0 0 6
New 329 160 1 0 0 0 6

January 2023 – 147 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 390 103 0 0 0 0 3
New 326 167 0 0 0 0 3