EPA’s Proposed Air Rules For New Masonry Heaters

Share on facebook
Share on linkedin
Share on twitter
Share on whatsapp
Share on email

Author – Oliver Beauchemin

On Jan 3, 2014, the U.S. Environmental Protection Agency (EPA) proposed updates to its air emission standards for new residential wood heaters that would strengthen the requirements for new woodstoves, while establishing air standards for several other types of wood heaters for the first time, including masonry heaters already in use in homes or currently for sale today.


  • A masonry heater is a solid-fueled home heating device that is built or assembled on site. A masonry heater consists of a firebox, and numerous heat exchange channels. Masonry heaters store heat from short, rapidly-burning fires and slowly release the heat throughout the day. Masonry heaters currently do not require EPA certification.
  • EPA’s proposed updates would limit the amount of particle pollution, also know as particulate matter (PM) from newly constructed masonry heaters. The proposed limits also are expected to reduce emission of other pollutants found in wood smoke.
  • The proposed rule would limit PM emissions for new masonry heaters to 0.32 pounds of PM per million British thermal units (BTU). This limit is based on test data for typical masonry heaters that perform well. Manufacturers would have to meet the emissions limit by one of two deadlines, depending on the number of heaters they build in a year.

Annual Production Level

Proposed PM Emissions limit

Compliance Deadline

 15 heaters or more

 0.32 pounds per million

 BTU heat output 

 60 days after final rule is published  in the Federal Register.

 Fewer than 15 heaters

 0.32 pounds per million

 BTU heat output

 5 years after the effective date of  the final rule.

  • Most pellet stoves are exempt from EPA’s current New Source Performance Standards (NSPS) for Residential Wood Heaters. Under the proposed rule, all pellet stove would have to meet same emission limit as for woodstoves, in the same two-step process.

Proposed Emissions Limits for New Woodstoves and pellet stoves


Proposed PM Limit

Compliance Deadline

 Step 1: For all stoves without  current EPA certification

·  4.5 grams per hour of operation for catalytic and noncatalytic stoves.

 60 days after final rule is  published in the Federal Register.

 Step 2: All woodstoves and  pellet stoves

·  1.3 grams per hour for catalytic and noncatalytic stoves

 5 years after the effective date  of the final rule.

EPA is also seeking comment on phasing in proposed emissions limits over eight years. This approach would include an interim emissions limit of 2.5 grams per hour three years after the final rule is published in the Federal Register. 


  • Each model line subject to the proposed rules would be required to demonstrate compliance through performance testing, similar to requirements of the current wood stove regulations. Under this certification program, one representative appliance is tested by an accredited laboratory to demonstrate compliance for an entire model line. EPA is proposing this approach rather than requiring manufacturers to test every heater to minimize testing costs to manufacturers, most of which are small businesses.
  • The proposed rule also includes test methods that manufacturers would have to use to determine PM emissions and demonstrate compliance.
  • To strengthen compliance assurance and consumer confidence, the proposed standards would require testing and certification by internationally accredited laboratories and certification bodies. EPA would also review the tests and make the results available to consumer on a website.

~ Oliver Beauchemin

~ Asking for Chimney Information ~

After reading an article, you can ask a question about that article. Replies will come from Chimney Professionals, and sometimes from homeowners, who are giving their answer based on the information you provide. Remember that they are providing answers SIGHT and SITE unseen! 

CHIMNEYS.COM recommends that you use these comments to better inform yourself to discuss your chimney and venting issues with a professional whom you call to your home to evaluate the issue.

To read more like the article above, click on the topic below...

Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments

Looking for a Chimney Sweep?

Click to find…

Your Chimney Pro

Scroll to Top