Forensic Engineering Critique Of The Methodology Eliminating Fire Cause Possibilities

Abstract

In A Case Involving A Residential Fire With Fatalities, Plaintiff Experts Alleged That The Fire Originated In A Bedroom As A Result Of An Electrical Failure In An Oscillating Pedestal Fan. At The Time Of The Fire, The Fan Was Plugged Into A Six Foot Extension Cord That Was Lying On The Floor Under The Bed And Plugged Into A Standard 115 Volt Duplex Receptacle. The Plaintiffs, Specific In Their Allegations, Opined That The Failure Occurred In The Rotary Switch That Controlled The Speed Of The Fan Even Though No Physical Evidence Of A Failure Of That Nature Was Identified Or Collected During The Analyses Of The Fire Scene. Since No Physical Evidence Of A Failure Was Identified, Nfpa 921, Guide For Fire & Explosion Investigations, Requires That All Other Potential Ignition Sources In The Area Of Origin Be Eliminated As A Possible Cause. Plaintiffs Eliminated The Power Cord For The Fan, The Extension Cord And The Cord Plug And Cord Receptacle Connection Under The Theory That The Material Was Pvc With A Vw-1 Fire Rating. Plaintiffs Testified That The Self Extinguishing Characteristics Of Vw-1 Material Were Such That, Even With An Electrical Failure In One Of Those Components That Resulted In The Ignition Of The Material, There Would Be Insufficient Heat Released To Ignite The Box Spring For The Bed. Plaintiffs Also Eliminated Improperly Discarded Smoking Material As A Potential Cause.Efendants Were In Sharp Disagreement With Plaintiff Case In Chief Regarding The Elimination Of The Vw-1 Materials As A Potential Fire Cause, Since The Material Will Combust In Situations With A Sustained Electrical Fault. Defendants Conducted Tests Which Not Only Demonstrated An Electrical Failure With Ignition At The Extension Cord Plug Receptacle Interface, But Also That The Burning Vw-1 Pvc Released Sufficient Heat Energy To Ignite A Box Spring Similar To The Box Spring Involved In The Fire. The Results Of Those Tests Assisted In The Resolution Of The Case Prior To Trial.