Processed on 2024-03-04 13:18:04 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 Maine spent in each AQI category during the the month of July.

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.

July in Maine

July 2014 – 6 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 73 16 0 0 0 0 39
New 53 36 0 0 0 0 39

July 2015 – 6 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 127 44 0 0 0 0 21
New 103 68 0 0 0 0 21

July 2016 – 15 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 172 6 0 0 0 0 14
New 143 35 0 0 0 0 14

July 2017 – 7 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 163 6 0 0 0 0 23
New 131 38 0 0 0 0 23

July 2018 – 18 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 185 14 0 0 0 0 25
New 151 48 0 0 0 0 25

July 2019 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 193 33 0 0 0 0 30
New 151 75 0 0 0 0 30

July 2020 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 236 5 0 0 0 0 15
New 217 24 0 0 0 0 15

July 2021 – 9 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 215 24 1 0 0 0 16
New 195 44 1 0 0 0 16

July 2022 – 9 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 263 11 0 0 0 0 14
New 233 41 0 0 0 0 14

July 2023 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 215 80 0 0 0 0 25
New 144 151 0 0 0 0 25