Processed on 2024-03-04 14:13:15 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 Washington spent in each AQI category during the the month of January.

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.

January in Washington

January 2014 – 30 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 730 155 0 0 0 0 14
New 592 293 0 0 0 0 14

January 2015 – 41 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 756 122 0 0 0 0 21
New 626 251 1 0 0 0 21

January 2016 – 112 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 925 176 4 1 0 0 41
New 815 286 4 1 0 0 41

January 2017 – 52 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 896 302 17 0 0 0 56
New 741 455 19 0 0 0 56

January 2018 – 130 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1274 145 1 0 0 0 37
New 1154 265 1 0 0 0 37

January 2019 – 67 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1331 258 8 1 0 0 76
New 1130 459 8 1 0 0 76

January 2020 – 129 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1676 100 2 0 0 0 51
New 1574 202 2 0 0 0 51

January 2021 – 71 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1594 216 6 3 0 0 72
New 1343 467 6 3 0 0 72

January 2022 – 83 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1596 288 9 5 0 0 24
New 1343 539 11 5 0 0 24

January 2023 – 106 permanent monitors

Good Moderate USG Unhealthy Very Unhealthy Hazardous Missing
Old 1924 196 1 0 0 0 111
New 1709 409 3 0 0 0 111