Processed on 2024-03-04 13:25:38 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 Minnesota spent in each AQI category during the the month of April.

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.

April in Minnesota

April 2014 – 17 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 417 26 0 0 0 0 22
New 386 57 0 0 0 0 22

April 2015 – 18 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 484 10 0 0 0 0 33
New 447 47 0 0 0 0 33

April 2016 – 37 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 497 30 0 0 0 0 31
New 434 93 0 0 0 0 31

April 2017 – 19 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 497 35 0 0 0 0 26
New 436 96 0 0 0 0 26

April 2018 – 40 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 533 30 0 0 0 0 26
New 463 100 0 0 0 0 26

April 2019 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 574 22 0 0 0 0 24
New 552 44 0 0 0 0 24

April 2020 – 42 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 585 35 0 0 0 0 31
New 541 79 0 0 0 0 31

April 2021 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 567 41 0 0 0 0 43
New 507 101 0 0 0 0 43

April 2022 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 592 4 0 0 0 0 55
New 569 27 0 0 0 0 55

April 2023 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 579 39 0 0 0 0 33
New 512 106 0 0 0 0 33