To make the fire debris interpretation process more standardized and objective, this article proposes a novel method for analyzing fire debris Gas Chromatography-Mass Spectrometry (GC–MS) data, using quantitative measures of chromatographic features of interest.
Chromatographic features of interest in 150 gasoline samples were evaluated, and 64 chromatographic peak height ratios were selected for study. Statistical analysis was conducted to determine the variation observed for each of these ratios in the gasoline samples and to determine the frequency of these features in negative matrix samples. This information was evaluated to determine relative significance, as represented by the assigned points for each of these features. When summed and used as plot values, these cumulative scores graphically display the separation of gasoline samples from negative matrix samples using this methodology. The scores were used to create a sufficiency graph, which is a graphical display detailing the totality of data supporting a potential gasoline identification. The sufficiency graph also identifies the “gray” area where analysts are more likely to form differing opinions.(Publisher abstract provided)