Processed on 2024-03-04 12:53:39 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 Connecticut spent in each AQI category during the the month of March.

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.

March in Connecticut

March 2014 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 168 68 0 0 0 0 12
New 113 123 0 0 0 0 12

March 2015 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 167 77 0 0 0 0 4
New 137 107 0 0 0 0 4

March 2016 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 195 30 0 0 0 0 23
New 176 49 0 0 0 0 23

March 2017 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 203 7 0 0 0 0 38
New 185 25 0 0 0 0 38

March 2018 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 230 6 0 0 0 0 12
New 222 14 0 0 0 0 12

March 2019 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 216 32 0 0 0 0 0
New 170 78 0 0 0 0 0

March 2020 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 219 14 0 0 0 0 15
New 205 28 0 0 0 0 15

March 2021 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 230 18 0 0 0 0 0
New 198 50 0 0 0 0 0

March 2022 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 194 53 0 0 0 0 1
New 157 90 0 0 0 0 1

March 2023 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 230 16 0 0 0 0 2
New 212 34 0 0 0 0 2