AQ Programs

The most significant sources of diesel exhaust in Oregon are on-road, heavy-duty diesel trucks and diesel construction equipment. These sources are identified in the Portland Air Toxics Study as among those creating the most public health risk through air toxics exposure. Additional sources of diesel exhaust include diesel engines used in locomotives and in marine vessels.

Diesel engines are used extensively throughout Oregon and the United States because of their proven reputation for reliability, durability, power and fuel efficiency. DEQ works with heavy-duty diesel owners and operators to access the benefits of diesel engines, while reducing their emissions through various strategies, including retrofitting or replacing older, dirtier engines, installing emission control devices or electrifying truck stops. These approaches not only decrease diesel exhaust, but help Oregon businesses save fuel and operational costs.

diesel emissions sources