Arson fire as a cause of explosion in limestone buildings

Abstract

This article covers the explosive collapse of buildings, constructed from limestone, brick and concrete, resulting from arson. Two case studies are presented which typify the phenomenon. It appears that as a result of overpressure formed inside the structure during an accelerated fire, venting occurs by lateral movement of the wall bricks in the upper courses, closest to the ceiling. This may lead to loss of support of the ceiling slab which then falls under gravity, causing further collapse of surviving walls. Although the destruction of the structure occurs with explosive violence, the forensic evidence from the scene of the crime usually allows a differentiation of this type of explosion from one caused by domestic gas or a bomb.