Processed on 2024-03-04 12:46:49 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 Arizona 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 Arizona

December 2014 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 271 157 2 1 0 0 3
New 184 244 2 1 0 0 3

December 2015 – 16 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 227 188 7 0 0 0 12
New 171 244 7 0 0 0 12

December 2016 – 34 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 323 150 1 0 0 0 22
New 217 256 1 0 0 0 22

December 2017 – 18 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 290 211 14 6 0 0 6
New 176 324 15 6 0 0 6

December 2018 – 36 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 370 146 5 0 0 0 6
New 294 222 5 0 0 0 6

December 2019 – 18 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 369 111 3 0 0 0 13
New 305 175 3 0 0 0 13

December 2020 – 39 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 385 181 14 3 0 0 6
New 296 268 16 3 0 0 6

December 2021 – 21 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 454 179 3 0 0 0 15
New 367 266 3 0 0 0 15

December 2022 – 23 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 420 191 9 6 0 0 25
New 303 308 9 6 0 0 25

December 2023 – 33 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 411 201 5 3 0 0 10
New 315 297 5 3 0 0 10