Summer’s in full swing with this upcoming holiday weekend, and social distancing guidelines in response to the pandemic have many of us entertaining in our backyards. This might include the comfort of a backyard fire. But even small fires contribute to poorer air quality by emitting fine particles and substances that are particularly harmful to people living with respiratory illness.
Air quality and health are closely linked, and even low levels of air pollution can worsen lung diseases such as asthma and COPD. And of particular concern now: Early research by Harvard University suggests that COVID-19 patients who live in cities with high levels of air pollution are more likely to die from the disease than those who live in less populated areas.
The good news is that Minnesota’s urban areas have less air pollution than many other major U.S. cities. But air pollution, including from “neighborhood sources” like fires and lawn mowers, remains a concern for those with respiratory conditions.
If you enjoy backyard fires, take steps to protect lung health and reduce air pollution:
- Burn only wood that has been left to dry for six months or more, or has been kiln-dried by a retailer. Dry wood is less smoky and releases less pollution than wet wood.
- Don’t burn anything other than clean, dry wood. This includes branches, leaves or other yard waste; cardboard; trash; or building materials like treated lumber or old fence posts, which leave toxic ash.
- If you cut your own firewood, split it, stack it, and cover it, allowing air to flow through — to ensure it gets dry and stays dry. Consider buying an inexpensive moisture meter to check the moisture content before using it. Only burn when moisture is 20% or less.
- Know your city’s rules around backyard fires. Some cities may only allow fires at certain times of day or require a permit. The Minnesota Fire Marshall requires all fires to be no greater than three feet in diameter and two feet high, located at least 25 feet from any structures that could catch fire, including fences or sheds.
- Be sure to completely extinguish the fire when you’re done. Do not leave your fire unattended, assuming it will burn out.
- Consider switching to fuels that produce less smoke, like natural gas or propane, which produce less than 1% of the particle pollution released from dry-wood fires. Kits to convert an existing fire ring or pit to natural gas or propane burners are available from hearth and patio stores.
One final consideration: Postpone fires on air quality alert days, when background levels of pollution are higher than normal. You can sign up to receive information about air quality conditions near you on the MPCA's Air Quality Index webpage.