Urban-Wildland Fires: On the Ignition Of Surfaces By Embers 1

An experimental apparatus has been built to investigate the ignition of surfaces as a result of impact with burning embers. The apparatus allowed for the ignition and deposition of both single and multiple embers onto the target surface. The moisture content of the surfaces used was varied and the test surfaces considered were pine needle beds and shredded paper beds. Embers were simulated by machining wood (pinus ponderosa) into small disks of uniform geometry and the size of the disks was varied. Ember simulation was necessary since it is difficult to capture and characterize embers from an actual burning object. The ember ignition apparatus was installed into the Fire Emulator / Detector Evaluator (FE/DE) to investigate the influence of an air flow on the ignition propensity of a surface. Results of this study are presented.