The number of people burning wood for backyard fires is growing according to annual wood burning surveys by the Minnesota Pollution Control Agency. Landscape architects also report that patio fire pits and outdoor fireplaces are one of their most commonly requested amenities.
Although its appeal is undeniable, burning wood releases fine particles and chemicals into the air. With so many people burning wood at home, backyard recreational fires have become a sizable source of fine-particle air pollution released into the air — especially in the Twin Cities metro area.
Burning wood and breathing the smoke from campfires can be hazardous to health. In fact, wood smoke has many of the same chemicals and health effects as tobacco smoke. People with asthma, or respiratory diseases, children under the age of 5, and the elderly can be more sensitive than others to the health effects of breathing wood smoke. How many of us know if our neighbors have asthma or lung disease? The first consideration in whether to have a backyard fire is how it might affect neighbors.
The best way to reduce exposure to wood smoke? Don't burn wood in the first place.
But if you choose to burn, here are a few ways you can reduce the amount of pollution released.
- Burn well-seasoned, dry wood. Wet wood burns at lower temperatures and releases more pollution than dry wood.
- If you use your own firewood, split it so it can dry better. Inexpensive moisture meters are available to determine moisture content. Use wood with no more than 20% moisture.
- Cover stacked wood with a tarp or store it under cover, with air flowing through it, so it can dry. Split hardwood can take a year or more to adequately dry.
Better yet, switching to cleaner fuels such as natural gas or propane will significantly reduce harmful air pollutants. The key to burning without producing unhealthy air pollutants is efficient combustion — the fuel has to completely convert into carbon dioxide and water, and this works best when burning flammable gases rather than solid fuels. Natural gas or propane fires produce less than 1% of the particulates released from burning even seasoned wood. Kits to convert an existing fire ring or pit to natural gas or propane burners are readily available from hearth and patio stores.
Many Minnesota households have reported burning fallen branches from their yards for disposal. To avoid this unnecessary source of air pollution, you can contact your city or county to learn how to dispose of your waste branches.
One final consideration is to refrain from having backyard fires on air quality alert days, when background levels of pollution are already higher. You can sign up to receive information about air quality conditions near you on the MPCA's Air Quality Index webpage. Improving air quality depends a lot on personal choices, and avoiding wood fires — or at least doing them right — is an easy choice to make.