Typically, when people think of sources of air pollution, they think about buildings with big smoke stacks like power plants and factories. Yet these sources make up a relatively small proportion of air pollution emissions in Minnesota. Today, most of the air pollution in Minnesota comes from smaller, more widespread sources.
- Permitted sources: Typically large, stationary sources with relatively high emissions, such as electric power plants and refineries.
- Non-permitted sources: Typically stationary sources, but generally smaller sources of emissions than permitted sources — dry cleaners, gasoline service stations and fires such as residential wood combustion, inadvertent or intentional agriculture burning, prescribed burning or forest wild fires.
- Mobile sources: Onroad vehicles: cars and trucks. Nonroad sources: off-road vehicles and portable equipment powered by internal combustion engines, lawn and garden equipment, construction equipment, aircraft, and locomotives.