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Certification and Compliance for Vehicles and Engines

How to get a copy of the Certificate of Conformity:

Certification and Compliance for Vehicles and Engines


(Includes motorcycles, passenger
cars and trucks, commercial trucks,
and buses)


(Includes aircraft, heavy equipment, locomotives, marine vessels, recreation vehicles, and small equipment and tools)


Engines and Vehicles Compliance Information System (EV-CIS), formerly the Verify System (for onroad and nonroad vehicles and engines)

Manufacturer Information and Guidance Letters

Learn more about manufacturer information and guidance letters, including how to find them by year issued and how to get notified when new letters are issued.

Search for Documents

Search EPA's Transportation and Air Quality
database for documents:
In the DIS, you can find:
  • Advisory circulars
  • Applications for certification
  • Certificates of conformity
  • Certificate summary information reports
  • Manufacturer guidance letters
  • EV-CIS (formerly Verify) documentation