List of certified wood stoves and wood-burning devices
Federal emission standards for wood stoves and pellet stoves are now more protective than Washington standards. All other wood-burning devices must still meet Washington standards.
Type of Device |
Washington PM2.5 Limit |
EPA PM2.5 Limit |
Catalytic1 wood burning device |
2.5 grams per hour |
2.0 grams per hour (tested with crib wood)3
2.5 grams per hour (tested with cord wood) |
Non-catalytic2 wood burning devices |
4.5 grams per hour |
2.0 grams per hour (tested with crib wood)3
2.5 grams per hour (tested with cord wood) |
Factory-built fireplaces and masonry heaters |
7.5 grams per hour |
voluntary limit |
1 Catalytic devices use a ceramic element to reduce smoke.
2 Non-catalytic devices use other engineering to reduce smoke.
3 Crib wood is lumber used specifically for wood burning emissions test methods.
Emission testing requirements for wood stoves
All wood heaters (wood stoves, pellet stoves, etc.) made after 1939 must be emission tested unless they meet the definition of a wood-fired cook stove. Heaters that also bake or cook do not qualify as wood-fired cook stoves.
In order to sell a wood heater, it must be tested at an EPA-certified lab using either a Category A – EPA approved method, or Category B – EPA approved alternative method.
Once testing is complete, email the wood stove coordinator with the:
- Make, model, and efficiency rating
- Test summary
The wood stove coordinator will review the information and contact you if more information is needed. Approved devices are listed in the "certified wood stoves" tab.
Type of stove |
Washington PM2.5 Limit |
More information |
Wood stoves, coal stoves, and corn stoves |
2.5 grams/hour for catalytic stoves
4.5 grams/hour for non-catalytic stoves |
|
Pellet stoves |
4.5 grams/hour |
|
Manufactured fireplaces (also known as low mass fireplaces or zero clearance fireplaces)
|
7.3 grams/hour |
Test the fireplace at an EPA-certified lab using Washington's fireplace test method (ASTM E2558). If a fireplace contains features to control the air-to-fuel ratio, it is considered a wood stove, and must be tested and approved as a wood stove. |
Indoor wood and pellet furnaces |
2.5 grams/hour for catalytic furnaces
4.5 grams/hour for non-catalytic furnaces |
|
Masonry heaters |
7.5 grams/hour
|
Test the masonry heater at an EPA-certified lab using Washington's fireplace test method. Manufacturers may apply for a testing exemption if a testing lab establishes that a device is substantially similar in design to an already-tested device. A Washington-approved process for this is available through OMNI test labs. |
Outdoor wood-fired boilers (residential) |
2.5 grams/hour for catalytic devices
4.5 grams/hour for non-catalytic devices |
Wood-fired boilers are not legal in Washington. EPA Method 28 OWHH is a Category C test that is not officially approved by EPA or Washington. |
Removing an uncertified wood stove is not required when you are buying or selling a house.
To help protect air quality, we encourage you to use cleaner home heating options, such as electric or natural gas. Recycle an uncertified wood stove.
Selling an uncertified wood stove is illegal. Wood stoves are certified when they are manufactured. A homeowner cannot apply to certify their wood stove.
Find out more about buying or selling a wood burning device in Washington.
Wood-fired cook stoves mostly used for cooking must have these features to be exempt from emission testing:
- A device to measure oven temperatures
- A flame path that is routed around the oven
- A soot clean-out door below the oven
- An oven with a volume of 1 cubic foot or greater, and an oven rack
- No fan or heat channels used to dissipate heat from the appliance
- A cooking surface measured in square inches or square feet that is 1.5 times greater than the firebox
- Part of at least four sides of the oven are exposed to the flame path while the oven is heating; a flue gas bypass is allowed to control temperature
- An ash pan
To install a wood-fired cook stove, work with your local building permit department to meet their requirements.
Check with your local clean air agency about limits to using your cook stove during a burn ban.
Consider other heating options before you buy or install a wood stove. Natural gas and electricity are much cleaner ways to heat your home. Use a wood stove or fireplace that is certified in Washington, the right size, and properly installed.
Many cities, counties, housing authorities, and utility companies offer grants, low-interest or interest-free loans, and/or free weatherization and conservation programs. Check with your local clean air agency for more information.