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Air Quality Program

Wood Stoves, Fireplaces, Pellet Stoves, and Masonry Heaters

A photograph of a certified stove.

Wood smoke is one of the main sources of air pollution in Washington. Wood stoves, fireplaces, and other wood burning devices put out hundreds of times more air pollution than other sources of heat such as natural gas or electricity.

This web site has information about burn bans, which wood burning devices are legal in Washington, why wood smoke is harmful to health, and how to reduce the smoke from your wood burning device.


Health concerns

The most dangerous material in wood smoke may be the fine particles that make up the smoke and soot. Many of these particles are toxic. Most are so small that, when you breathe them, they get past your body’s defenses and go deep into your lungs. There, they can cause serious problems such as scarring of the lung tissue. Studies show that death rates in several U.S. cities increased when there were higher levels of fine particles in the air. Wood smoke is most dangerous to the health of infants and children, pregnant women, the elderly, and people with lung or heart disease. Some of the reasons wood smoke is such a serious problem are:

  • Almost all the wood smoke in Washington is released during winter months. This means it is very concentrated. It takes just three months for wood smoke to become Washington’s third leading source of air pollution.
  • In the winter, we often have weather conditions that cause stagnant air. As a result, wood smoke is trapped close to the ground in neighborhoods. At these times, air pollution in many neighborhoods is unhealthy.
  • Studies show that people who heat their homes with wood have more respiratory problems than those who don’t. Smoke particles also invade neighboring homes. Research shows that children in wood burning neighborhoods are more likely to have lung and breathing problems.

Washington's wood stove/pellet stove requirements

To protect health, Washington has strict laws about wood stoves and other wood burning devices. Most states use federal Environmental Protection Agency (EPA) emission standards for fine particles to determine which wood burning devices can be sold. To be sold in Washington, all wood burning devices must meet both EPA’s standards and Washington’s stricter standards.

Fine particle emission standards

Type of Device Washington Limit EPA Limit
Catalytic wood burning device 2.5 grams per hour 4.1 grams per hour
Non-catalytic wood burning devices 4.5 grams per hour 7.5 grams per hour
Factory-built fireplaces and masonry heaters 7.3 grams per kilogram no limit

Any wood burning device sold, offered for sale, or given away to Washington residents must meet Washington’s standards. Even devices that are exempt from EPA certification must meet Washington standards. Wood burning devices include:

  • wood stoves
  • pellet stoves
  • wood furnaces
  • manufactured fireplaces
  • masonry heaters

Other Washington requirements

  • Burn only wood that has a moisture content of no more than 20 percent. Wood that is split and then dried for at least a year usually meets this requirement.
  • It is illegal to burn some materials. Illegal materials include garbage, treated or painted wood, particle board, plastics, rubber, waste petroleum products, animal carcasses, asphalt products, paints, chemicals, or anything that normally emits dense smoke or obnoxious odors.
  • Smoke density is restricted. Smoke plumes can have no more than 20 percent opacity. This means you should see only heat waves coming from your chimney. If you can see smoke coming from your chimney, you're wasting fuel and your fire needs more air. (It’s okay to have more smoke only when you are starting or stoking a fire.)
  • There is a $30 fee on the sale of new solid fuel burning devices. This includes wood stoves, pellet stoves, coal stoves, manufactured fireplaces, masonry heaters, wood furnaces, or any other devices that burns a solid fuel. The fee pays for wood stove education and enforcement programs. More information about the fee is available from the Department of Revenue.
  • Non-wood heat sources are required in new or significantly remodeled construction.
  • A local air quality agency or Ecology may prohibit the use of uncertified stoves under certain conditions. Usually, this happens when an area fails to meet federal air quality standards.
  • Air quality agencies call burn bans when wood smoke pollution reaches unsafe levels. Burn bans have two stages:
    • Stage 1: The use of all uncertified wood heating devices is banned when pollution approaches unhealthful levels.
    • Stage 2: All wood heating is banned when pollution reaches an even higher level.

Burn bans do not apply to homes with no other source of adequate heat. All outdoor burning is also banned during burn bans. Find out if there is a burn ban in your area

Choose the right wood burning device

Use a wood stove or fireplace that is certified in Washington, the right size, and properly installed:

Is your firewood ready to burn?

If you use a wood stove or fireplace, now is the time to make sure your firewood is covered and out of the weather.

Wet firewood boils when it burns. With wet wood, it can be harder to get a fire going and keep it burning. Wet firewood also makes a smoky fire with little heat, and wastes wood. So, it just makes sense to burn dry firewood. Wood that has been split, dried and stored under cover for at least six months usually burns best. Here's how to make sure your wood is dry enough to burn:

  • If you buy wood from an independent firewood seller, ask them if the wood has been properly seasoned. It should have been dried under cover for at least six months. If not, you will need to dry it for several months before you can burn it.
  • Use a moisture meter to check the moisture content of split firewood. The goal is less than 20 percent moisture content.

And remember - burning small, hot fires gives you more heat and less smoke!

If you burn, burn clean

If you heat with wood, you can reduce smoke by burning properly:

  • Burn only dry, seasoned wood. Be sure your firewood has been split and dried for at least one year. Store it under cover.
  • Never burn wet, painted, stained or treated wood; colored newsprint; plastic; garbage; diapers; or magazines.
  • Build small fires to help the wood burn completely. Adding too much wood at one time cuts down on the air to the fire and leaves you with unburned wood.
  • Keep your fire hot. Dampering down your stove just cuts off the air, which wastes wood, creates a lot of smoke, and produces very little heat. You can tell if your fire has enough air by checking the smoke coming from your chimney. You should see only heat waves. If you see smoke, increase the air supply to your fire.
  • Make sure your wood stove is the right size for its space. A stove that is too large for the space it is heating will have to be damped down, causing more smoke. Make sure your stove is properly installed.

Buying or Selling a Home with an Uncertified Wood Stove

Removing an uncertified wood stove is not required when you are buying or selling a house. We encourage using cleaner home heating options and recycling uncertified stoves.

Selling an uncertified wood stove is illegal. Selling a house with an uncertified wood stove is legal.

Wood stoves are certified when they are manufactured. Homeowners cannot apply for wood stove certification.

Other information

Contact Us


How you burn makes a difference in your pocket and in the air

> More blogs about wood stoves


Find out if there is a burn ban in your area


Manufacturer information

List of wood stoves that meet Washington standards (11/1/16)

List of pellet stoves that meet Washington standards (9/8/16)

List of fireplaces that meet Washington standards (5/4/16)

List of masonry heaters that meet Washington standards (10/10/16)

List of wood-fired hydronic heaters that meet Washington standards (4/27/17)

List of wood-fired furnaces that meet Washington standards (12/15/16)

Information about wood-fired cook stoves