Processed on 2024-03-04 14:13:06 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 Virginia spent in each AQI category during the the month of December.

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.

December in Virginia

December 2014 – 7 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 174 27 0 0 0 0 16
New 136 65 0 0 0 0 16

December 2015 – 7 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 155 34 0 0 0 0 28
New 137 52 0 0 0 0 28

December 2016 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 180 4 0 0 0 0 2
New 162 22 0 0 0 0 2

December 2017 – 9 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 169 17 0 0 0 0 0
New 146 40 0 0 0 0 0

December 2018 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 165 14 0 0 0 0 7
New 134 45 0 0 0 0 7

December 2019 – 7 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 158 47 0 0 0 0 12
New 128 77 0 0 0 0 12

December 2020 – 14 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 184 31 0 0 0 0 2
New 143 72 0 0 0 0 2

December 2021 – 7 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 154 31 0 0 0 0 1
New 108 77 0 0 0 0 1

December 2022 – 12 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 210 61 0 0 0 0 8
New 159 112 0 0 0 0 8

December 2023 – 26 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 360 82 0 0 0 0 8
New 304 138 0 0 0 0 8