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Vehicle and Engine Certification

Private Vehicle Testing: EPA’s In-Use Vehicle Emissions Surveillance Program

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Program Overview

EPA tests cars before, during, and after production to make sure that vehicles not only meet emission standards when they are new, but also remain compliant years later. The new vehicle component of EPA’s compliance oversight testing generally involves manufacturer-owned vehicles. To evaluate the emissions performance of older vehicles, EPA borrows cars and small trucks from private owners and tests them at its National Vehicle and Fuel Emissions Laboratory (NVFEL) in Ann Arbor, Michigan. EPA tests about 150 customer-owned vehicles per year through this surveillance program.

The purpose of the in-use vehicle testing program is to assess whether the emissions controls continue to perform effectively after vehicles have been driven for several years. The testing program supplies important information for both manufacturers and EPA. Sometimes the information leads to an emissions recall. Other times, the testing reveals issues with a certain technology or design feature, enabling manufacturers to introduce modifications that improve emission control system performance or durability in future models.

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How Does EPA Recruit Vehicles for Testing?

EPA typically recruits two- or three-year-old vehicles from volunteers in southeast Michigan. To identify potential volunteers, we obtain registration information from the Michigan Secretary of State that lists owners of vehicles we are interested in testing. We select the surveillance vehicles both randomly and based on targeted factors such as certification data, manufacturer in-use data, vehicle production volume, new technology, and public complaints and inquiries.

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What to Expect if EPA Contacts You

EPA conducts the in-use surveillance program with the assistance of Jacobs Engineering Group, an EPA contractor.

If you are identified as the owner of a vehicle we are interested in testing, you will receive an information package in the mail. The packet includes further information about the program, along with forms for you to complete and return. Participation in the program is entirely voluntary. The mailing outlines your choices as a participant, including whether you want a loaner vehicle while yours is being tested, along with the other types of incentives available to surveillance program participants. If you choose to participate in the program, Jacobs will contact you to coordinate vehicle pickup and to arrange for delivery of a loaner if you choose that option.

When your vehicle arrives at NVFEL, we will inspect it and prepare it for testing. All tests are conducted by EPA's highly trained staff in a state-of-the-art laboratory that uses specialized equipment to precisely measure your car’s exhaust and evaporative emission levels.

When testing is complete, Jacobs will deliver your vehicle back to you along with a compensation check. Before return, your car or truck will be washed, vacuumed, and filled with fuel.

This important program depends upon the public’s assistance. We thank participants for their assistance and willingness to support EPA and its mission.

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In-Use Vehicle Emissions Surveillance Program Forms and Letters

  • EPA Letter Sample
  • Jacobs Letter Sample
  • Sample Reply Form
  • Sample Jacobs Driving Data Release Form

Frequent Questions

Frequent questions regarding the program (PDF) (3 pp, 442 K, February 2020, EPA-420-F-20-007, About PDF)

Information about EPA's Lab

Learn more about EPA’s National Vehicle and Fuels Emissions Laboratory (NVFEL).

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