Search

Share |
Climate SMART: Be cool - reduce global warming & climate risks

WOOD SMOKE POLLUTANTS & WOOD STOVE EFFICIENCY

Wood burning is a greater source of air pollution than other home heating choices. To avoid wood smoke pollutants, far and away the best solution is to consider switching to alternative fuels such as oil, propane, or natural gas. You can convert your existing fireplace to oil, gas, propane or electricity with a fireplace insert. These heating options produce far fewer volatile organic compounds (VOCs) and particilate matter (PM) than wood heating for the same cost.

Operate Your Wood Stove Properly

If you choose to burn wood, there are several practices to increase wood stove efficiency and lower emissions levels into the atmosphere:

    • Obtain firewood in late winter/early spring to ensure firewood is seasoned & sheltered from weather for 6  months. Seasoning firewood will reduce wood consumption by up to 25%
    • Firewood size is important: Smaller pieces burn more cleanly because more surface area is exposed to the flame. Wood should be split to maximum thickness of 10-15 cm, depending on stove size, and should be 10 cm shorter than the firebox
    • Careful control of the air supply determines how completely the fuel is burned. When you start a fire or add wood to it, the fresh fuel requires much more air for the first 10 to 15 minutes. Once the wood is well charred, the amount of air required drops off
    • Loosely packed pieces burn faster since combustion air can reach all pieces at once. To maintain a consistently clean burn, refuel your stove frequently with suitably sized loads of wood before the previous load is completely consumed, and the firebox cools.

To monitor your wood stove’s performance, watch both the fire and what comes out of the chimney. As the wood decomposes in your firebox, it vaporizes into smoke. The smoke will burn in a bright yellow-blue turbulent flame. Secondary combustion produces bright, lively flames. Conversely, dull, steady flames are a sign of oxygen starvation and incomplete combustion.

A sure sign of poor combustion is excessive smoke from a chimney. Unburned gases either leave the chimney as air pollution (Particulate matter and volatile organic compounds), or condense in the chimney as dangerous creosote. Some smoke may be visible when you first light the fire, but for the remainder of the burn the flue gases should be almost invisible. Dampening or holding your fire overnight by cutting down on the air supply is not a recommend practice because it creates excessive emissions, and promotes the formation of creosote.

Burn Wood More Efficiently

Improving your wood stove’s combustion efficiency will automatically reduce wood smoke emissions. For example, do not burn plastics, household garbage, rubber, asphalt products, chemical substances, painted or treated wood, or manufactured wood products. Burning these materials releases even more harmful air pollutants, and may damage catalytic combustors in catalytic wood stoves. Finally, to improve overall combustion, and decrease emissions from conventional wood stoves, you should use an EPA-certified wood or pellet stove.

Text Box:  	Work the Web  Canadian Lung Assoc: Reducing Wood Smoke