Forensic Engineering Analyses of a Home Fire

Abstract

A fire had occurred in a single-family home where a family of four was living. The family was asleep whenthe daughter woke up, saw smoke in her bedroom, and screamed. The daughter and father exited by breaking through a bedroom window, but the other two family members were overcome by the fire before exiting (and were later found deceased by the fire department). None of the witnesses heard a smoke detector (activation), and brief searches by investigators did not find any evidence of either the detector bracket or other remains. Forensic engineering analyses of the preserved evidence were performed, and Fire Dynamics Simulator (FDS) software was used to analyze multiple fire origins, predicted smoke-detector activation, and egress times. Fire growth, thermally induced electrical failure (THIEF), glass breakage, smoke-detector activation, barrier failure, and tenability (CO, temperature and visibility) were calculated. The FDS analyses were performed using a combination of factual information, timelines, fuels derived from the Fire Burning Item Database (FireBID), analyses of photographs, and witness depositions, and were verified and validated. The analyses/methodologies were explained to the trier of the facts (jury), and the results were presented; namely, the most probable origin and cause (ignition) of the fire, smoke-detector-activation times, and egress times for the residents.