Processed on 2024-03-04 13:05:34 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 March.

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.

March in Illinois

March 2014 – 11 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 178 146 4 0 0 0 13
New 112 212 4 0 0 0 13

March 2015 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 247 88 0 0 0 0 37
New 161 174 0 0 0 0 37

March 2016 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 264 58 0 0 0 0 19
New 172 150 0 0 0 0 19

March 2017 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 363 36 0 0 0 0 35
New 292 107 0 0 0 0 35

March 2018 – 40 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 535 93 0 0 0 0 23
New 406 222 0 0 0 0 23

March 2019 – 23 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 449 194 0 0 0 0 39
New 316 327 0 0 0 0 39

March 2020 – 43 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 522 107 0 0 0 0 53
New 398 231 0 0 0 0 53

March 2021 – 23 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 471 145 0 0 0 0 66
New 343 273 0 0 0 0 66

March 2022 – 24 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 562 111 0 0 0 0 40
New 435 238 0 0 0 0 40

March 2023 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 586 119 0 0 0 0 8
New 393 312 0 0 0 0 8