EPA-Approved Test Labs and Third-Party Certifiers for Residential Wood Heaters

EPA is committed to ensuring that new wood stoves and other wood burning devices comply with Clean Air Act standards to reduce health-harming pollution.

In light of information from states and other stakeholders provided in late 2020 and early 2021, the agency is taking a number of actions to address concerns about the methods and manner in which new wood stoves are being tested for compliance with the 2015 New Source Performance Standards under the Clean Air Act.  

Since the 2015 rule, EPA has relied on the Third-Party certification review and assurances that the test reports coming from test laboratories are accurate and represent all required documentation collected in a manner consistent with regulatory requirements and specific test method criteria. Findings identified recently by stakeholders indicate that there may be serious and systematic problems to be addressed in the Third-Party Certification process. 

In February 2021, EPA sent letters to the laboratories and the third-party verifiers notifying them that EPA was taking actions to ensure that the testing and certification of wood burning appliances is being conducted appropriately. 

These actions will take time and continued engagement with stakeholders.  Please check back to this website for additional information.

Improving Testing and Certification 

• After discussion with the State of Alaska, EPA sent letters to each EPA-Approved Test Laboratory and EPA-Approved Third-Party Certifier putting them on notice that EPA is reviewing all of the test reports identified by Alaska and others and that we expect that the labs and certifiers will work to provide their clientele with updated and appropriate reports.
• We also expect that they will adjust their standard operating procedures to ensure that such deficiencies are not found in future test reports.
• Also in February 2021, EPA approved a new, broadly applicable test method for wood stoves, known as the Integrated Duty Cycle (IDC) test method, in response to a request filed by the State of Alaska.  Any manufacturer may use this test method to demonstrate compliance with the New Source Performance Standards.
• On February 23, 2022, EPA withdrew certain cordwood test methods that manufacturers have relied on to certify compliance with the NSPS. These are Alternate Test Method ALT-125 and Alternate Test Method ALT-127.  This decision was the result of a review initiated at the request of the State of Alaska and several other State environmental programs.

Reviewing Certification Submissions

• EPA is reviewing the more than 240 currently certified wood heater test reports identified in the March 2021 NESCAUM (Northeast States for Coordinated Air Use Management) report and will take actions, as appropriate, to make sure that only compliant devices are available on the market for the public.
• In addition, EPA is increasing the integrity of its review of all test reports for new woodstove certification applications to ensure that they are compliant before they go on the market.

Improving the Test Method

• EPA is undertaking a multi-year project to develop improved compliance measurement methods for testing new woodstoves which better reflect real-world conditions. 
• The agency is working with states and other stakeholders across industry and laboratories to collect and review data and solicit feedback on the testing prior to proposal of the new test method. 

Documents

• List of Wood-Fired Appliance Test Report Deficiency Items- Subpart AAA - Wood Heaters and Pellet Heaters (pdf) (181.51 KB, March, 2023)
• February 3 and February 25, 2021 letters from US EPA to EPA-Approved Third Party Certifiers for Residential Wood Heaters and Residential Wood Burning Appliance Laboratories.
• Table of EPA-Approved Test Labs and Third Party Certifiers