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Vehicle and Engine Certification

Transition Program for Equipment Manufacturers (TPEM)


The Transition Program for Equipment Manufacturers, better known as “TPEM” or “flexibility program,” is a temporary exemption that allows diesel equipment manufacturers to delay installing Tier 4-compliant engines in their products for up to seven years.

TPEM was created in response to equipment manufacturers’ concerns that engine manufacturers would not provide sufficient notice of possible changes in engine design stemming from tighter standards. Therefore, they would not be able to make the necessary adjustments to their equipment to accommodate these design changes within the timeframe provided by the regulations.

Many TPEM participants are small businesses.

Participants must comply with certain production limitations and paperwork requirements.

Who can participate

TPEM is only available to diesel equipment manufacturers that:
  • Have primary responsibility for designing and manufacturing their own equipment, AND
  • Install the engine(s).

Companies that import TPEM equipment into the U.S. but do not manufacture equipment do not qualify to participate in TPEM on their own. They can only participate as an importer by bringing equipment into the US that is exempted under an equipment manufacturer’s valid exemption.

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Regulatory Requirements for TPEM

There are different requirements for:

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Application and Reporting Steps for Equipment Manufacturers and Importers

STEP 1: Review the applicable requirements, choose your allowance, and plan out your TPEM participation.
STEP 2: Before you use any TPEM allowances, apply by downloading and completing the applicable template below.
STEP 3: Submit your completed notification and any other applicable information to EPA.

STEP 4: When ordering engines, provide the engine manufacturer with written assurance that the engines will be used under TPEM.

STEP 5 (IMPORTERS ONLY): Before importing your TPEM equipment, post a bond or apply for a bond waiver.
STEP 6: Keep adequate production records for all exempted equipment.
STEP 7: Download and complete the annual report template.
STEP 8: Submit annual reports by March 31 of the year after you use TPEM allowances.

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Recordkeeping and Reporting Steps for Engine Manufacturers

STEP 1: Keep adequate production and sales records.
STEP 2: Download and complete the annual report template.
STEP 3: Submit annual reports by March 31 of the year after you use TPEM allowances.

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Additional Tools and Tips

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TPEM Help Desk

For questions about TPEM, contact the help desk.

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