In fire debris analysis, analysts compare chromatograms of extracts of fire debris to a database containing chromatograms of ignitable liquid reference standards. Typically, the database will contain chromatograms of experimentally evaporated liquids. Unfortunately, experimentally evaporating ignitable liquids can be a time-consuming process. Previously, a mathematical model was developed with diesel that predicts the evaporation rate constant of compounds as a function of retention index (IT). The model can be used to generate predicted chromatograms of evaporated liquids. In comparing predicted to experimental chromatograms, predictive accuracy was high for comparisons using diesel, torch fuel, and marine fuel stabilizer.This research aims to improve the predictive accuracy of the model with respect to gasoline and to test the feasibility of developing correlation coefficient ranges for the classification of an ignitable liquid residue as gasoline. Improvement of the predictive accuracy of the model involved changes to the instrumental parameters and data analysis procedures. The feasibility of development of PPMC coefficient ranges involved comparisons of predicted reference collections of a non-gasoline ignitable liquid to chromatograms of experimentally evaporated gasoline.
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