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Verified Technologies for SmartWay and Clean Diesel

Requirements for Verification of Clean Diesel Technology

Before applying for verification of your Clean Diesel Technology, consider the following:

On this page:

Regulatory requirements

Some technologies may not qualify for verification as the product may have regulatory requirements that supersede verification. For example, manufacturers that convert diesel engines to operate on alternative fuels (CNG or LNG) must follow the regulatory requirements for certification and consequently these engine conversions could not use the verification process. 

Additionally, some technologies may have regulatory requirements that must be addressed prior to applying for verification. For example, there may be regulatory requirements for safety or health effects that need to be addressed.

Fuels and fuel additives are not included in the verification program for Clean Diesel Technology. Instead, these technologies must comply with the Fuel Programs requirements.

Documentation requirements

In order for EPA to evaluate a technology, manufacturers will be required to provide clear explanation and documentation of:
  • How the technology works
  • Basis for emission reduction claims
  • Intended market application and engine groups
  • Potential unique testing needs
  • Operating criteria, including any operating constraints (e.g., ambient air temperature or conditions, backpressures, etc.)
  • Potential concerns for health or safety
  • How and where the technology is installed on the vehicle
  • Experience with in-use operation of the specific technology and similar designs
  • Previous testing

Requirements for the applicant

The person applying for verification must be an official manufacturer representative with detailed knowledge of the technology, its manufacture, in-use operation, performance, durability and prior testing.

The manufacturer representative is responsible for attesting to EPA that:
  • All information submitted for application is correct;
  • The technology will be manufactured and installed as described;
  • The technology will perform as described.

Requirements for availability of technology

The retrofit technology submitted for verification must be commercially available for installation. No products still in the research and development stage will be verified.

Requirements for health effects and safety of technology

Concerns with health effects or safety may need to be addressed prior to EPA review of a technology for verification.

Requirements for intended market for technology and documentation from in-use experience

Manufacturers should identify specific engine and vehicle types for the intended market segment, and provide documentation from in-use experience. EPA has grouped together engine families with similar emissions performance characteristics for verification purposes. The retrofit manufacturer may provide test data showing that a product tested on one engine family may be applied to other similar engine families.

For more information, see: Engine Family Groups for Verification of Clean Diesel Technology

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