A Burning Issue

January 11, 2002

By Michael Jessen

Go for a walk almost anywhere these cold winter days and you're likely to catch the scent of wood smoke in the air.

Blue or grey wood smoke curling out of a home chimney is often thought cozy, even romantic. But in some communities and neighbourhoods, wood smoke is becoming a burning issue.

The problem is the very fact that the wood smoke CAN be seen and smelled. Although there is no record of any human community without use of fire, it appears many of us have not learned how to use it properly.

Homey and appealing as wood smoke seems, it has become a major cause of air pollution and the cause of serious chronic health problems for some British Columbians. For these reasons, it is important for anyone who operates a wood stove to understand the effects of smoke, and to control it.

With more than 20 years experience cleaning chimneys, selling and installing wood stoves in the Kootenays, Jim Moore says the secret of heating with wood comes down to two things: the stove you choose and the way you use it.

"Too many people have 30 per cent or more of their wood stove heat going up the chimney," says Moore who operates Jim's Chimney Sweep Service. Walk by his Longbeach Road home and all you'll see are shimmering waves of heat emanating from his chimney -- the sign of a properly burning wood stove.

Got a lot of visible smoke coming out of your chimney? That's an indication of incomplete combustion and energy going to waste. More smoke also means more flammable creosote deposits in your chimney, making you a prime candidate for Moore's chimney sweep services.

"Reducing Wood Stove Smoke" is the title of a BC government pamphlet initially produced in 1994 and available online at http://wlapwww.gov.bc.ca/air/particulates/rwssabi.html. It has many excellent suggestions about how to choose a wood stove and operate it properly. A wood stove certified by the U.S. Environmental Protection Agency can reduce smoke emissions by as much as 90% compared to conventional stoves, and are much more efficient. "If your existing stove is more than 7 years old, consider getting one of the new advanced combustion units. You won't regret it," suggests the pamphlet.

Natural Resources Canada has produced "A Guide to Residential Wood Heating," also available online at www.nrcan.gc.ca/es/erb/reed/wood/. The section on burning wood efficiently points out that the knowledge and skills needed to operate a wood-burning system effectively do not come to us automatically just because we are Canadian and live in a cold climate. They must be learned and practised to get them right.

According to Moore, most smoke emanating from wood fires is due to operator error.

A great source for consumer safety information is the web site www.wetbc.com, operated by the provincial governing body of the Wood Energy Technical Training Program of BC, Canada's only system for training and recognizing professional competence in the field of residential woodburning. You'll find a series of 12 fact sheets covering everything from buying firewood, safe operation and maintenance, and even fireplace operation.

Two Kootenay residents currently serve on the board of directors of Wood Energy Technicians of BC -- Doug Burton of Kootenay Furnace in Slocan is vice-president and David Butt of Silver Arrow Chimney Service in New Denver is a director. Moore is a former director of the organization.

John Gulland is widely known as the Canadian guru of wood heating. Visit his web site at www.gulland.ca/ to learn how he heats his 2,000 square foot Killaloe, Ontario home with a modest wood stove that re-burns the smoke and virtually eliminates the chance of a chimney fire caused by creosote build-up. Gulland recommends the web site www.woodheat.org.

There are materials that Gulland warns should never be burned in a wood stove. Among them are household garbage, pressure treated wood, plastics, and painted wood that all release very toxic chemicals. He advises sticking to seasoned firewood.

Air-dried hardwood, seasoned for a year, is the best cord wood fuel. Most people in BC burn softwoods and they should be seasoned for at least six months, preferably a year. Fresh-cut wood is between 35 and 50 percent water by weight. Burning wet or green wood means much of the heating value of the wood is lost burning off the excess moisture. It also means more smoke and creosote.

Another common problem creating smoke is people who burn improperly sized wood. When wood is large, it burns very slow, again creating smoke that has no heat in it.

Containing over 100 different chemicals -- including acrolein, formaldehyde, carbon monoxide, nitrogen oxides, volatile organic compounds, dioxin, and furan -- wood smoke can aggravate respiratory disease. Several wood smoke pollutants have demonstrated cancer-causing properties similar to cigarette smoke. In addition, wood smoke emitted from the chimney contains fine particles that are so small they can easily enter neighbouring homes as well. The publication "Health Effects of Wood Smoke" written by the Washington State Department of Ecology and downloadable from www.ecy.wa.gov/biblio/92046.html gives all the nasty details.

So keep an eye on your fire and your chimney emissions. Give your wood fire oxygen when you refuel, especially if adding wood on smouldering coals. Staying warm is a good thing, but breathing and staying healthy are far more important -- and neighbourly -- values.

ONE SMALL STEP - A fire should not be left to smoulder during the night to keep the house warm, since smouldering wood causes tremendous air pollution. The more slowly and incompletely something burns, the greater chance it has to release smoke and toxic gases into the air. During a smouldering fire, the chimney will not be receiving the hot gas it needs to produce a strong draft. Invest in a new stove that can hold its fire for 24 hours.

Michael Jessen is the owner of toenail environmental services and helps businesses and communities find sustainable solutions to environmental problems. He can be reached at 229-5632 or e-mailed at toenail@netidea.com. His firm's award-winning web site is at www.toenail.org/.


All columns archived here are copyright © 2000 by Michael Jessen, all rights reserved. If you wish to print an individual column for your own use, please do so. If you wish to publish any of the columns in either print or electronic format, please contact the author at toenail@netidea.com to arrange appropriate payment.