Pierce, Washington Air Quality
Pierce County, Washington (WA)
→ Stableover 10 years
10-Year AQI Trend
The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days).
Air Quality Day Breakdown
Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).
Year-by-Year Data
| Year | Median AQI | 90th Pct | Max AQI | Good Days | Moderate | Unhealthy+ | Pollutant |
|---|---|---|---|---|---|---|---|
| 2023 | 42 | 62 | 195 | 273 | 89 | 3 | Ozone |
| 2022 | 44 | 70 | 178 | 239 | 115 | 11 | Ozone |
| 2021 | 42 | 61 | 94 | 269 | 96 | 0 | Ozone |
| 2020 | 42 | 66 | 256 | 256 | 99 | 11 | Ozone |
| 2019 | 44 | 67 | 142 | 234 | 129 | 2 | PM2.5 |
| 2018 | 44 | 74 | 188 | 234 | 120 | 11 | Ozone |
| 2017 | 45 | 74 | 176 | 242 | 110 | 13 | Ozone |
| 2016 | 42 | 58 | 156 | 269 | 96 | 1 | PM2.5 |
| 2015 | 44 | 67 | 166 | 235 | 123 | 7 | PM2.5 |
| 2014 | 42 | 67 | 114 | 251 | 112 | 2 | PM2.5 |
What This Means for Pierce County Residents
Pierce, Washington has received an Air Quality Grade of C (63/100) based on a decade of monitoring data from the EPA's air quality monitoring program. The current median AQI of 42 falls in the "Good" range.
The primary pollutant affecting this area is Ground-Level Ozone. Over the past 5 years, this area has averaged 5 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity. The American Lung Association's State of the Air report provides additional context on long-term health risks from air pollution exposure.
Related Cities in Washington
Frequently Asked Questions
Pierce, Washington has a current median AQI of 42, which falls in the "Good" range. The area has received an Air Quality Grade of C (63/100) based on 10 years of EPA monitoring data.
Air quality in Pierce, Washington is stable over the past decade. The median AQI has changed by 0 points from 2014 to 2023.
Pierce, Washington averages 5 unhealthy air quality days per year over the past 5 years. On these days, sensitive groups including children, the elderly, and those with respiratory conditions should limit outdoor activity.
The primary pollutant affecting Pierce, Washington is Ground-Level Ozone. This is the dominant contributor to elevated AQI readings in the Pierce County area.
Pierce, Washington averages 5 unhealthy air days per year. This is relatively low, making it a reasonable choice for asthma sufferers. The primary pollutant is Ground-Level Ozone, which is a known asthma trigger.
With a median AQI of 42 (Good), outdoor exercise in Pierce, Washington is generally safe year-round. Pierce, Washington averages 5 days per year when athletes should move workouts indoors.