Processed on 2024-03-04 14:20:31 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 Wyoming spent in each AQI category during the the month of September.

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.

September in Wyoming

September 2014 – 5 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 119 0 0 0 0 0 5
New 114 5 0 0 0 0 5

September 2015 – 5 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 133 4 0 0 0 0 18
New 126 11 0 0 0 0 18

September 2016 – 11 permanent monitors

Processing error: Unable to calculate tables.

September 2017 – 5 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 66 16 2 1 0 0 8
New 61 21 2 1 0 0 8

September 2018 – 11 permanent monitors

Processing error: Unable to calculate tables.

September 2019 – 3 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 88 0 0 0 0 0 5
New 87 1 0 0 0 0 5

September 2020 – 15 permanent monitors

Processing error: Unable to calculate tables.

September 2021 – 15 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 218 75 5 0 0 0 12
New 182 111 5 0 0 0 12

September 2022 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 293 51 1 0 0 0 27
New 263 80 2 0 0 0 27

September 2023 – 18 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 394 17 3 2 0 0 18
New 388 23 3 2 0 0 18