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About Diesel Fuels

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Diesel Fuel Used in Transportation

Diesel fuel is used to power highway vehicles and nonroad engines and equipment such as:

  • Diesel cars
  • Trucks
  • Farm, construction, and mining equipment
  • Ships
  • Locomotives

Diesel engines and vehicles make up about a third of the entire transportation fleet in the U.S.   

Diesel is the predominant fuel used for shipping goods and moving freight across the country and around the world.

Why EPA Regulates Diesel Fuel 

The amount of sulfur in diesel fuel is directly linked to the amount of pollution produced when the fuel is burned in an engine. Higher levels of sulfur increase pollutants.

When diesel fuel is burned in engines, the emissions that result contributes to air pollution that has serious human health and environmental effects.

Pollution from diesel exhaust includes:

  • Soot or particulate matter (PM);
  • Oxides of nitrogen (NOx) which contributes to the production of ground-level ozone (smog) and acid rain; 
  • Hydrocarbons (HC);
  • Carbon monoxide (CO); and
  • Other hazardous air pollutants (HAPs) and air toxics.

This air pollution can cause heart and lung disease and a range of other health effects.  It can also damage plants, animals, crops, and water resources.

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Diesel Fuel Additives

EPA defines fuel additives as products formulated to enhance the quality and efficiency of fuels. EPA regulates additives because they impact emissions. The list below provides the current diesel fuel additives currently registered with EPA. 

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