Updated: June 2014

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Unregulated Wood Stoves

Wood stoves began to be regulated in 1988 so all the stoves sold before then are unregulated, and they virtually all are far more polluting and less efficient than the EPA certified stoves made since then. However, about 40,000 thousands of new, unregulated wood stoves are still being sold every year in the US because of a loophole in EPA regulations allows cheap, inefficient and usually very polluting stoves to stay on the market. Older and newer uncertified stoves usually do not have glass in the door.

A nice looking Stove Unregulated by the EPA
Some of these unregulated stoves may look deceptively like more efficient stove designs.
A nice looking Stove Unregulated by the EPA
Other unregulated stoves have designs more obvious in their lack of efficiency and emission technology.
This loophole is likely to be closed in 2015 when the EPA updates their regulations. The EPA allows these stoves to escape regulation because they are purposefully built in such a way as to not meet the agency's criteria for a wood heater. Numerous jurisdictions do not allow their installation including Washington, Oregon and most of California. Most of the populated areas of Colorado and Utah do not allow them either.

While some of these stoves are used infrequently in remote hunting cabins, work sheds and garages, many are installed in neighborhoods in small towns or suburban areas where they emit much more smoke pollution than what should be allowed in a dense residential area. Sometimes they have even been advertised as "Meets EPA Requirements", implying that the stoves are approved by the EPA. Our goal is for companies that sell EPA exempt stoves to agree on better language to use in their advertisements, so consumers can more easily understand the difference between EPA exempt and EPA certified stoves.


Rumsford 1000 fireplace insertThe advanced Rumford 1,000 fireplace emits only 3.94 grams per hour with the door closed.

Fireplaces are generally the least efficient wood burning technology of all, their open design limiting the user’s ability to control a fire or burn at temperatures high enough to ignite all wood combustion products.  Luckily, most fireplaces are used only occasionally, not as a source of home heating.

New fireplace technology has been recently developed to help make fireplaces a more clean wood-burning option. Renaissance Fireplaces received a Clean Air Excellence award for their Rumford 1,000 model. By sealing off the fireplace to only take in outside air, they’ve manage to produce a fireplace which exceeds Washington State emission standards and achieve 70-93 percent fewer emissions than a typical fireplace.

The EPA has also developed a set of voluntary standards for fireplaces, available here. The site includes a list of qualifying fireplaces as well as program partners.

The designers at Earth's Flame have developed a new and innovative product aimed at reducing harmful fireplace pollution. Their strategy has forgone removing pollution from the fire and have instead taken aim at the source of the pollutions itself, a poorly burning fire. This hybrid wood/gas stove both reduces emissions and increases efficiency, for more details, you can find the report here.

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