Forensic Examination of Post-Fire Damaged Electrical Conductors by Quantitative Measurement
Keywords:Fire Investigation, microstructure, porosity, metallography, arc mapping, arc survey, electrical fault, arcing, electrical, forensic engineering, fault, short circuit, conductors, copper
During their course of work, forensic engineers and electricians may apply electrical engineering and scientific principles to forensic investigations by performing electrical surveys and electrical fault evaluations. When undertaking a fire investigation, an investigator may implement a similar electrical fault methodology called “arc mapping” or more recently termed an “arc survey.” The correct application of either of these methodologies is dependent, in part, on the forensic investigator’s ability to distinguish features observed on damaged electrical wiring and equipment. Experiments were conducted to generate a post-fire damaged electrical artifact dataset for this engineering analysis. Generated artifacts of arc melting, fire melting, and mechanical damage features were examined, measured, and quantified by applying metallurgical analyses, such as visual examination, measurement, light microscopy, SEM/EDS, X-ray, and/or metallographic examination. The results produced a novel proof of concept method of quantifying and reliably identifying electrical conductor damage features for forensic electrical fault (short circuit) and/or arc survey evaluations.
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