Processed on 2024-03-04 13:05:24 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 February.

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.

February in Illinois

February 2014 – 11 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 137 143 0 0 0 0 28
New 91 189 0 0 0 0 28

February 2015 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 216 69 0 0 0 0 23
New 148 137 0 0 0 0 23

February 2016 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 230 63 0 0 0 0 26
New 173 120 0 0 0 0 26

February 2017 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 257 115 0 0 0 0 20
New 204 168 0 0 0 0 20

February 2018 – 40 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 400 164 0 0 0 0 24
New 278 286 0 0 0 0 24

February 2019 – 23 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 341 189 0 0 0 0 58
New 196 334 0 0 0 0 58

February 2020 – 43 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 501 89 0 0 0 0 48
New 357 233 0 0 0 0 48

February 2021 – 23 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 382 183 0 0 0 0 51
New 217 347 1 0 0 0 51

February 2022 – 24 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 445 166 0 0 0 0 33
New 331 280 0 0 0 0 33

February 2023 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 563 87 0 0 0 0 22
New 405 245 0 0 0 0 22