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  1. Home
  2. Verified Technologies for SmartWay and Clean Diesel

Testing for Verification of Clean Diesel Technology

  • Overview
  • Requirements
  • Application
  • Supplemental Info
  • Testing
  • Evaluation

Follow these steps for the testing part of the verification process:

1. Develop a test plan and obtain approval.

After completing the Application portion of the process, the manufacturer will select a qualified test facility, work with EPA to develop a test plan, and get approval from EPA for testing.

2. Provide devices to the test facility.

Upon approval of the test plan, the manufacturer will provide the following devices
to the test facility:
  • A de-greened device (25-125 hrs of operation);
  • An aged device (1000 hrs of operation);
  • Full sets of installation instructions and operating manual(s); and
  • A test engine if the test facility does not have a suitable engine for testing.

3. Conduct testing.

The device manufacturer is responsible for:
  • Ensuring that testing follows the test plan, even if a contract facility conducts the testing;
  • Accurately reporting to EPA during testing to resolve any concerns or issues.

If necessary, EPA may observe some or all of the testing.

4. Go to the Evaluation phase.

Once all data, test reports, and associated documentation are submitted to EPA, a technology is evaluated in the final phase of verification.  
Click this link or the tab above: Evaluation for the Verification Process.

Verified Technologies for SmartWay and Clean Diesel

  • Clean Diesel Technology
    • Learn About
    • Verified List
    • Verification Process
    • Manufacturer Contact List
  • SmartWay Technology
    • For Trucks & School Buses
      • Designated Tractors
      • Designated Trailers
      • Refrigerated Trailers and TRU Calculator
      • Aerodynamic Devices
      • Idling Reduction
      • Tires
    • For Locomotives
    • For Marine Technology
Contact Us about Verified Technologies for SmartWay and Clean Diesel
Contact Us about Verified Technologies for SmartWay and Clean Diesel to ask a question, provide feedback, or report a problem.
Last updated on April 28, 2025
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