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Burn Wise

Cord Wood and Crib Wood Testing


May 15, 2020 -- EPA is proposing amendments to the 2015 New Source Performance Standards for New Residential Wood Heaters, New Hydronic Heaters and Forced-Air Furnaces (collectively referred to as “wood heating devices”). Due to the nation-wide spread of the COVID-19 virus, the proposed amendments, if finalized, would provide retailers more time to sell Step 1-certified residential wood heating devices. 

EPA, along with State and industry stakeholders, believes emissions testing using cord wood is important because it presents a more realistic picture of emissions from wood heaters in daily use. Manufacturers of wood burning devices who must meet the Final New Source Performance Standards (NSPS) for Residential Wood Heaters can test emissions using cord wood.

While not required, manufacturers choosing to test with cord wood need to have prior EPA approval.

Crib wood is a specified configuration and quality of dimensional lumber and spacers, usually cut 2”x4” or 4”x4” lumber improve the repeatability of wood burning emissions test methods. (See Figure 1)

Cord wood, also called firewood, is what a typical homeowner uses, and is a more accurate measure of how a wood heater will perform in homes. (See Figure 2)

In the preamble to the NSPS, commenters overwhelmingly agreed that cord wood testing better represents real-world conditions, provides better information for consumers to choose the cleanest and most efficient heaters and that the EPA should encourage cord wood testing. Thus, the final regulation includes a cord wood alternative compliance option for Step 2 and allows voluntary, temporary EPA hangtags for devices tested with cord wood.

Roundtable Information

EPA held a roundtable discussion on January 15, 2020 in Research Triangle Park, NC with states, wood heat appliance manufacturers, and other stakeholders to inform the Agency’s direction toward a cord wood-based compliance test method for emissions from residential wood heaters, such as wood stoves. After hearing from these stakeholders about the need for a reproducible method that reflects the real usage of these heaters, EPA will begin work to replace the federal test method based on data provided by an Integrated Duty Cycle (IDC) Protocol established by New York State Energy Research and Development Authority (NYSERDA). Over the next several months, EPA will facilitate the open sharing of available data, which will be discussed at a second roundtable later this year.  EPA will also work with all stakeholders to identify and then collect sufficient additional data, which will be discussed at a third roundtable in the future. Notes from this meeting will be posted on this page. EPA has opened a non-regulatory public docket ( for posting and receiving information on this effort.