Abstract
The objective of this study is to predict the flame spread probability over urban fire by the ratio of non-combustible area to combustible area (porosity). This paper described the experimental results of flame spread experiments along randomly arranged combustible cubes. Flame spread experiments conducted with changing porosity and size of experiment region. Porosity of flame spread probability set to 0 increased with the increase of experiment region. Subjected to finite size scaling in experimental results and examined the influence of number of grid on flame spread probability.