Processed on 2024-03-04 13:31:00 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 Missouri spent in each AQI category during the the month of December.

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.

December in Missouri

December 2014 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 240 129 0 0 0 0 3
New 186 183 0 0 0 0 3

December 2015 – 13 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 326 61 0 0 0 0 16
New 267 120 0 0 0 0 16

December 2016 – 27 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 322 65 0 0 0 0 16
New 264 123 0 0 0 0 16

December 2017 – 13 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 300 63 0 0 0 0 9
New 254 109 0 0 0 0 9

December 2018 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 306 63 1 0 0 0 2
New 229 140 1 0 0 0 2

December 2019 – 13 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 257 109 0 0 0 0 6
New 183 183 0 0 0 0 6

December 2020 – 27 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 281 122 0 0 0 0 0
New 207 196 0 0 0 0 0

December 2021 – 14 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 343 58 0 0 0 0 2
New 253 148 0 0 0 0 2

December 2022 – 13 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 303 67 0 0 0 0 2
New 247 123 0 0 0 0 2

December 2023 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 344 14 0 0 0 0 2
New 303 55 0 0 0 0 2