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Vehicle and Engine Certification

Regulatory Requirements for Equipment Manufacturers to Participate in the Transition Program for Equipment Manufacturers (TPEM)

Overview of Requirements

Applicable Regulations

Equipment manufacturers:
  • Must meet eligibility criteria
  • Must sign up for the program by submitting a notification before exempting (“flexing”) any equipment
  • Must request TPEM engines in writing and assure the manufacturer that the engines will be used under TPEM
    • While TPEM engines are not certified to current standards, they must meet certain emission requirements
  • Each year of participation, equipment manufacturers must demonstrate compliance with the allowance they have selected for each power category by keeping adequate production records for all exempted equipment and submitting annual reports to EPA

Equipment Provisions

Equipment can be exempted for up to seven years.

The number of pieces of equipment that can be exempted or “flexed” vary depending on the type of allowance and power category.

Power Categories

There are two options for power categories:
  • General availability OR
  • Delayed availability
Program availability varies per power category.


  • Must choose one of two allowances:
    • Percent of Production Allowance OR
    • Small Volume Allowance, which is:
      • Single engine family, OR
      • Multiple engine families
  • Can claim only one allowance per power category for the life of the program.

For more information, see: Allowances for TPEM

Notification, Reporting, and Recordkeeping Requirements

For more information, see: Notification, reporting, and recordkeeping requirements

Importing Equipment

If you import your equipment into the US, see also: