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Regulations for Emissions from Vehicles and Engines
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Final Rule for Clean Alternative Fuel Vehicle and Engine Conversions

Final Rule for Clean Alternative Fuel Vehicle and Engine Conversions
Basic Information
Code of Federal Regulations Citations
  • 40 CFR Part 85
  • 40 CFR Part 86
Docket Numbers
  • EPA-HQ-OAR-2009-0299

On this page:

  • Rule Summary
  • Rule History

Rule Summary

EPA is streamlining the process by which manufacturers of clean alternative fuel conversion systems may demonstrate compliance with vehicle and engine emissions requirements. Specifically, EPA is revising the regulatory criteria for gaining an exemption from the Clean Air Act prohibition against tampering for the conversion of vehicles and engines to operate on a clean alternative fuel. This final rule creates additional compliance options beyond certification that protect manufacturers of clean alternative fuel conversion systems against a tampering violation, depending on the age of the vehicle or engine to be converted.

  • Final Rule (PDF) (46 pp, 821 K, published April 8, 2011, About PDF)
  • Response to Comments (PDF) (65 pp, 832 K, EPA-420-R-11-002, March 2011, About PDF)

Rule History

  • Proposed Rule and Related Materials
  • Regulations for Emissions from Vehicles and Engines Home
  • Onroad
  • Nonroad
  • Greenhouse Gas
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Last updated on June 27, 2022
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