Fifty-seven percent of the outdoor air pollution in Washington state is caused by motor vehicles. Industrial facilities account for 14%; residential wood burning (fireplaces and wood stoves) 10%; and outdoor burning (yard waste, land-clearing debris, forest slash, and agricultural burning) 6%. The remaining 13% is attributed to sources such as boats and other recreational vehicles, gas-powered lawn mowers and yard tools, etc.

• Breathe Easy Network
  Consisting of over 1,400 individuals, including the medical community, legislative network, those active with the association's asthma, air quality and lung disease programs and interested individuals.
• Facts About Diesel Exhaust
  Diesel exhaust is a major source of air pollution, which contributes to lung and other types of cancer.
• Wood Smoke Pollution
  Wood stoves and fireplaces account for about 10% of Washington's overall air pollution problem.
• Facts About Particulate Matter Air Pollution (PDF)
  An informative brochure about soot and dust pollution.
  
• Clean Air Is Up To You
  Simple ways to keep the air clean.
• Get a Check-Up for Your Car
  Frequent maintenance can keep your car cleaner.