Processed on 2024-03-04 13:05:14 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 Illinois 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 Illinois

January 2014 – 11 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 269 37 0 0 0 0 35
New 220 86 0 0 0 0 35

January 2015 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 230 57 0 0 0 0 85
New 139 148 0 0 0 0 85

January 2016 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 246 77 0 0 0 0 18
New 188 135 0 0 0 0 18

January 2017 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 311 108 2 0 0 0 13
New 215 204 2 0 0 0 13

January 2018 – 40 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 478 145 0 0 0 0 28
New 273 350 0 0 0 0 28

January 2019 – 23 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 432 186 0 0 0 0 33
New 281 337 0 0 0 0 33

January 2020 – 43 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 436 166 0 0 0 0 80
New 290 312 0 0 0 0 80

January 2021 – 23 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 458 197 0 0 0 0 27
New 296 359 0 0 0 0 27

January 2022 – 24 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 571 130 0 0 0 0 12
New 377 324 0 0 0 0 12

January 2023 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 506 223 0 0 0 0 15
New 323 406 0 0 0 0 15