Processed on 2024-03-04 13:49:39 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 Ohio 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 Ohio

April 2014 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 291 100 0 0 0 0 43
New 215 176 0 0 0 0 43

April 2015 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 421 46 0 0 0 0 29
New 346 121 0 0 0 0 29

April 2016 – 32 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 381 78 0 0 0 0 37
New 271 188 0 0 0 0 37

April 2017 – 18 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 453 35 0 0 0 0 70
New 373 115 0 0 0 0 70

April 2018 – 39 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 466 44 0 0 0 0 48
New 387 123 0 0 0 0 48

April 2019 – 20 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 504 64 0 0 0 0 21
New 428 140 0 0 0 0 21

April 2020 – 40 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 514 44 0 0 0 0 62
New 423 135 0 0 0 0 62

April 2021 – 24 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 484 115 0 0 0 0 52
New 375 224 0 0 0 0 52

April 2022 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 728 44 0 0 0 0 34
New 615 157 0 0 0 0 34

April 2023 – 41 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 714 153 0 0 0 0 94
New 535 332 0 0 0 0 94