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Transportation Air Quality Facts and Figures January 2006

Emissions Sources

Emissions Sources Categories

Point and Area Sources

Electric utilities and other fuel combustion
industrial processes such as:

  • Manufacturing
  • Painting and surface coating
  • Metals and chemical processing
  • Dry cleaners, gas stations and others
cartoon of a factory

On-Road Vehicles

  • Automobiles and motorcycles
  • Light duty trucks (minivans, pickup trucks, sport utility vehicles)
  • Heavy duty trucks
  • Buses
cartoon of a semi truck

Non-Road Engines

  • Lawn and garden equipment
  • Construction equipment
  • Farm equipment
  • Aircraft
  • Boats and other marine vessels
  • Railroads and other
cartoon of a lawn mower

Miscellaneous Sources

  • Wildfires and agricultural fires
  • Health services
  • Cooling towers
  • Windblown dust
cartoon of a camp fire
Updated: 3/17/2015
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