Sensitivity study on forest fire breakout and propagation conditions for forest fire hazard curve evaluations

Okano, Yasushi; Yamano, Hidemasa   

This paper presents a sensitivity study of the hazard curves on condition parameters where frequency and probability variables in the logic tree vary within respective fluctuation ranges. With regard to "fluctuation of breakout time of a forest fire", the hazard curves on the reaction intensity and the fireline intensity increased around 4% and 14% respectively on intensity. As for "probability distribution fluctuation of breakout point", the reaction intensity and the fireline intensity vary within around +70% to -40% on frequency. "Firefighting effect on a probability of forest fire arrival at an nuclear power plant" remarkably increase the hazard curves around 40 to 80 times. It only affects the frequency of the hazard curves. This study indicated that the most significant factor in the forest fire hazard curve is whether the firefighting action outside an nuclear power plant is expected before the arrival.