Processed on 2024-03-04 14:03:51 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 Tennessee spent in each AQI category during the the month of April.

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.

April in Tennessee

April 2014 – 6 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 113 65 0 0 0 0 8
New 50 128 0 0 0 0 8

April 2015 – 6 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 158 21 0 0 0 0 7
New 118 61 0 0 0 0 7

April 2016 – 13 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 150 25 0 0 0 0 11
New 94 81 0 0 0 0 11

April 2017 – 7 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 113 26 0 0 0 0 16
New 83 56 0 0 0 0 16

April 2018 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 190 17 0 0 0 0 10
New 165 42 0 0 0 0 10

April 2019 – 8 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 184 17 0 0 0 0 47
New 150 51 0 0 0 0 47

April 2020 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 203 16 0 0 0 0 29
New 174 45 0 0 0 0 29

April 2021 – 9 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 207 31 1 0 0 0 9
New 166 72 1 0 0 0 9

April 2022 – 10 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 190 37 0 0 0 0 21
New 147 80 0 0 0 0 21

April 2023 – 11 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 247 51 0 0 0 0 12
New 198 100 0 0 0 0 12