Fire ember production from wildland and structural fuels

Title: Fire Ember Production from Wildland and Structural Fuels
Authors: Aixi Zhou, Ph.D., P.E., North Carolina A&T State University, Stephen L. Quarles, Ph.D. Insurance Institute for Business & Home Safety, David R. Weise, Ph.D. Forest Service PSW-Forest Fire Lab-Riverside

Project proposal abstract

Spot fires caused by wind-blown burning embers (also called firebrands) are a significant mechanism of fire spread in the wildland and Wildland-Urban Interface (WUI). Fire spread and structure ignition by embers can be understood in three major processes or mechanisms: ember production, ember transport, and ember ignition of fuel. Considerable work on ember transport has been conducted, but much less work has been done to understand fire ember production and fire ember ignition of fuels. Fire ember production from various fuel types under different conditions is the basis for validating fire behavior models and developing mitigating strategies in the wildland and WUI. Thus, the purpose of the proposed project is to investigate ember production from selected burning wildland and structural (construction materials) fuels under a range of environmental conditions through full-scale, intermediate-scale and small-scale laboratory experiments. Specific objectives include the following: (1) Determine the basic thermal decomposition and combustion properties (at small scale) of selected fuels under a range of heating rate, radiant heat flux, and MC levels; (2) Determine the production rate, mass, shape and dimensions of embers (at full-scale) from burning wildland and structural fuels under a range of wind, radiant heat flux, and MC levels; (3) Determine the travel distance of embers as a function of mass, shape and dimensions (at full-scale) under a range of wind speed and fuel MC levels; (4) Determine the burning duration and intensity of embers as a function of mass and shape (at small and intermediate scales) under a range of wind, radiant heat flux, and MC levels; and (5) Evaluate the impact of these properties on ignition potential and fire spread in the WUI. The proposed fundamental research will improve our understanding of ember production and characteristics under realistic wildfire conditions. The results from this project will benefit various agencies with a mission to mitigate the fire damage in the wildland and WUI.

See the final report and other related publications.