Processed on 2024-03-04 13:56:01 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 Pennsylvania spent in each AQI category during the the month of May.

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.

May in Pennsylvania

May 2014 – 2 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 35 27 0 0 0 0 2
New 23 39 0 0 0 0 2

May 2015 – 3 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 17 19 0 0 0 0 28
New 9 26 1 0 0 0 28

May 2016 – 31 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 36 24 0 0 0 0 4
New 23 37 0 0 0 0 4

May 2017 – 3 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 74 14 0 0 0 0 8
New 56 32 0 0 0 0 8

May 2018 – 52 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 45 43 0 0 0 0 8
New 26 62 0 0 0 0 8

May 2019 – 28 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 425 75 0 0 0 0 76
New 325 175 0 0 0 0 76

May 2020 – 75 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 956 15 0 0 0 0 85
New 883 88 0 0 0 0 85

May 2021 – 42 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1064 191 0 0 0 0 57
New 850 405 0 0 0 0 57

May 2022 – 45 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1102 135 0 0 0 0 75
New 912 325 0 0 0 0 75

May 2023 – 46 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 791 306 1 0 0 0 54
New 612 485 1 0 0 0 54