Processed on 2024-03-04 13:21:59 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 Massachusetts spent in each AQI category during the the month of June.

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.

June in Massachusetts

June 2014 – 9 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 207 11 0 0 0 0 61
New 160 58 0 0 0 0 61

June 2015 – 9 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 249 19 0 0 0 0 11
New 221 47 0 0 0 0 11

June 2016 – 20 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 250 3 0 0 0 0 26
New 226 27 0 0 0 0 26

June 2017 – 10 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 214 28 0 0 0 0 37
New 184 58 0 0 0 0 37

June 2018 – 24 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 263 28 0 0 0 0 50
New 227 64 0 0 0 0 50

June 2019 – 14 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 372 18 0 0 0 0 44
New 322 68 0 0 0 0 44

June 2020 – 28 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 392 7 0 0 0 0 35
New 309 90 0 0 0 0 35

June 2021 – 17 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 397 56 0 0 0 0 74
New 303 150 0 0 0 0 74

June 2022 – 17 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 434 9 0 0 0 0 53
New 401 42 0 0 0 0 53

June 2023 – 19 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 363 144 20 7 0 0 24
New 292 215 20 7 0 0 24