Burning Behavior of Liquid Fuel and Burn Damage to Floorboards in Arson Cases with Liquid Fuel

In Japan, an arson crime against a building is considered to have been committed when a part of the building is burned irrespective of the arson medium. Since no evaluation method has been established for burn damage to building materials by liquid fuels, there is a lack of evidence for arson crimes to buildings with liquid fuels. In this study, the ignition time and burning rate of wooden floorboards were measured using a cone calorimeter. Burning experiments were conducted using liquid fuel in a full-scale building in which the floorboards were laid. Further, to evaluate the burn damage inside the floorboards, three-dimensional images of the burned floorboards were captured using an X-ray computed tomography (X-ray CT) system. The results of the burning experiments revealed the burning behavior of liquid fuel in buildings with a limited air supply. Three-dimensional imaging of the burned floorboards using an X-ray CT system enabled us to observe burn damage inside the wooden floorboards and confirm the difference in the degree of burn damage depending on whether or not the floorboard continued to burn independently of liquid fuel flame. The X-ray CT system is expected to be used as an analytical tool for providing evidence of burn damage to floorboards in liquid fuel fires.