Fire Safety Science Digital Archive

This paper describes the results of an experimental study of free-convective flame spread over the surface of a paper sheet soaked with a combustible liquid. Effects of volatility on the flame spread processes over the surface of a combustible were examined. It was shown that aspects of flame spread depended on the characteristic of the paper sheet. When the flash point was below the ambient temperature, a flame spread so fast that the leading flame edge reached the end before pyrolysis of paper began. To the contrary when the flash point was above the ambient temperature a leading flame edge extended ahead of the brown zone indicating pyrolysis of paper. In both cases the flame was seen to spread at a steady rate. The flame spread rate over a paper sheet soaked with combustible liquid is larger than that over a dry one. However, the flame spread rate across the free surface of a liquid fuel was larger than that over a paper sheet soaked with the same liquid. The difference in the flame spread rate is attributable to the effect of volatility.