Processed on 2024-03-04 12:52:23 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 July.

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.

July in Colorado

July 2014 – 19 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 299 30 0 0 0 0 23
New 220 109 0 0 0 0 23

July 2015 – 19 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 264 21 8 1 0 0 26
New 226 59 8 1 0 0 26

July 2016 – 30 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 314 16 0 0 0 0 22
New 230 100 0 0 0 0 22

July 2017 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 361 26 0 0 0 0 29
New 267 120 0 0 0 0 29

July 2018 – 41 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 349 60 0 0 0 0 39
New 227 182 0 0 0 0 39

July 2019 – 20 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 380 4 0 0 0 0 64
New 343 41 0 0 0 0 64

July 2020 – 39 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 429 13 0 0 0 0 38
New 362 80 0 0 0 0 38

July 2021 – 27 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 313 177 0 0 0 0 54
New 205 285 0 0 0 0 54

July 2022 – 34 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 523 4 0 0 0 0 17
New 496 31 0 0 0 0 17

July 2023 – 147 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 476 12 0 0 0 0 24
New 449 39 0 0 0 0 24