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Verified Technologies for SmartWay and Clean Diesel

Reducing Harmful Diesel Emissions

Reducing harmful emissions from diesel engines is a public health goal that depends on controlling diesel emissions.  Diesel retrofit technologies have been verified to reduce the following pollutants:

  • Particulate matter;
  • Nitrogen oxide;
  • Hydrocarbons; 
  • Carbon monoxide; and
  • Carbon dioxide.

EPA offers funding for projects that use EPA or California Air Resources Board (CARB) verified or certified diesel emission reduction technologies. Retrofit technologies are evaluated by EPA and CARB and verified technology lists are maintained by each program.  

EPA is committed to ongoing research, modeling, and analysis to provide the best and most accurate information available about fuel-saving technologies.

EPA collaborates with industry leaders to provide fleet managers and truck owners with the tools and information they need to make smart purchasing decisions and reduce their environmental impact while saving money in the process.

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