Wildland Urban Interface Fire Smoke Characterization

With millions houses in the US located at the wildland urban interface (WUI) and wildfire activity on the rise, there is a concern that structure fires might be a key source of air pollutants in WUI regions. Experiments were conducted to study the burning characteristics and smoke emission from mixed fuel crib assemblies designed to represent the main components in structures. Cribs consisting of wood, drywall, and plastics were assembled into cubic structures, all with the same mass fraction for each material. Three packing densities and two crib sizes were studied. While a crib burned to completion, the smoke was collected in a fire calorimetry system for the heat release rate (HRR), combustion gases, and smoke measurements. The scale of cribs affected the burn duration and the total heat release, but the packing density had a greater effect on modified combustion efficiency, peak HRR, and the emission factors of CO2, CO, formaldehyde, acrolein, SO2, and total hydrocarbons. This work contributes to the understanding of emissions and environmental impacts from WUI fires.