Proper width calculation to a firebreak line to protect flame spread from forest fire

Abstract

Building a firebreak line against forest fire spread is a typical indirect suppression method that stops spread of flame by removing fuel, such as trees and bushes. In the view of fire dynamic, building a firebreak line is to set a section which will block thermal energy from igniting on virgin fuel. This study suggests and evaluates a calculation method for width of firebreak against forest fires for variant wind and slope conditions by applying the Point Source Model (PSM) to Korean fuel types. Width of firebreak was measured based on the distance the threshold radiant heat igniting forest surface fuels wat the heat flux of 4.9kW/㎡ from surface and crown fires in forest. This study applied the condition of wind and slope as the wind velocity of 0~5m/s and the slope of 0~50°. As a result, Proper width of a firebreak line was calculated 1.1m in surface fires and 14.6m in crown fires. Additional comparative analyses through experiments and field surveys are deemed necessary to determine appropriate widths of firebreak for different types of surface fuel.