Pollutant emission factors for outdoor recreational fire pits

Abstract

Outdoor recreational wood burning, such as fire pit use, can produce large amounts of smoke which contains fine particulate matter (PM) and other air pollutants. Recently, purported “smokeless”, or low-smoke, fire pits have become widely available. Motivated by the apparent public desire for low-smoke options and the prospect of reducing PM pollution, the U.S. Department of Agriculture, Forest Service, collaborated with the Minnesota Pollution Control Agency to measure air pollutant emissions from low-smoke fire pits. We measured emission factors (EF) for PM (EFPM), carbon monoxide, methane, and carbon dioxide for two low-smoke fire pits and a campground fire pit. Our study average EFPM = 2.2 (±1.1) g kg-1 (g of PM emitted per kg of dry firewood consumed; mean ± one standard deviation) is 80 percent lower than that used in the U.S. EPA National Emission Inventory (NEI), EFPMNEI (11.3 g kg-1) for outdoor residential burning.

Citation

Urbanski, Shawn P.; Lincoln, Emily N.; Baker, Stephen P.; Nordgren, Bryce; Baggett, Larry Scott; Jackson, Anne; Belmont; Erica L.; McLaughlin, Luke P. 2025. Pollutant emission factors for outdoor recreational fire pits. Gen. Tech. Rep. RMRS-GTR-449. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 74 p. https://doi.org/10.2737/RMRS-GTR-449.