What is particle pollution?
Particle pollution, also called particulate matter (PM), is a mixture of tiny solids or liquid droplets that includes smoke, soot, dirt, and dust floating in the air. Common sources are:
- Wood stoves and fireplaces
- Dust from construction and agriculture
- Outdoor burning
- Industrial facilities
When we breathe, our nose or sinuses capture many of the particles in the air before they get to our lungs. However, smaller particles may escape these defenses and move deeper into our lungs, causing health problems. For this reason, Ecology monitors two specific size ranges of small particles:
- PM10 — particles less than 10 micrometers
- PM2.5 — particles less than 2.5 micrometers
Maintaining clean air
Today, all of Washington meets air quality standards for particle pollution, but there are several areas of concern that are being watched closely. To make sure the air continues to meet air quality standards, we and our partners monitor the air at 55 sites using Washington's Air Monitoring Network.
- Twenty-two are in urban areas (the Puget Sound region, Vancouver, Spokane, and Yakima Counties, and the Tri-Cities).
- Nineteen are in small communities outside of urban areas that have local sources of PM2.5 pollution.
- Seven are in agricultural areas and are used to inform agricultural burning decisions.
- Six are in tribal areas. These monitors are run by our tribal partners.
- One is in a natural rural location on the Olympic Peninsula.
Areas of concern for particulate matter