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Verified Technologies for SmartWay and Clean Diesel

  • Reducing Harmful Diesel Emissions

    Learn how using retrofit technologies reduces important pollutants. 

SmartWay Technologies

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EPA-verified technologies that save fuel and reduce emissions for:
  • Trucks and school buses
  • Locomotives
  • Marine technology

Technical Resources

TRU Emissions Calculator

Research and tools that may help fleets and technology developers.

  • Transport Refrigeration Unit Calculator
  • Tractor-Trailer Geometries for CFD



     

Clean Diesel Technologies

graphic displaying vehicles moving from dirty smog into bright clean air
EPA-verified retrofit technologies save fuel and reduce emissions.
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If you didn’t find the information you were looking for, you may want to search EPA’s Web Archive.

What's New

  • Tractor-Trailer Geometries for CFD
  • Refrigerated Trailers and Transport Refrigeration Units (TRU) Calculator
  • Tire casings used in retread testing
Related Topics
  • SmartWay Program
  • Diesel Emission Reduction Act (DERA) Program
  • Ports Initiative
  • State and Local Transportation
  • Heavy Duty Regulations and Standards
  • Fuels Registration, Reporting, and Compliance Help
  • CARB Verification
List of Verified Technologies
  • Aerodynamic Devices
  • Clean Diesel and Marine Technology
  • Low Rolling Resistance New and Retread Tire Technologies
  • Idling Reduction Technologies for Trucks and School Buses
  • Idling Reduction Technologies for Locomotives
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on March 28, 2025
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