Principal components analysis PCA, linear discriminant analysis LDA, and quadratic discriminant analysis QDA were used to develop a multistep classification procedure for determining the presence of ignitable liquid residue in fire debris and assigning any ignitable liquid residue present into the classes defined under the American Society for Testing and Materials ASTM E 1618-10 standard method.
Principal components analysis PCA, linear discriminant analysis LDA, and quadratic discriminant analysis QDA were used to develop a multistep classification procedure for determining the presence of ignitable liquid residue in fire debris and assigning any ignitable liquid residue present into the classes defined under the American Society for Testing and Materials ASTM E 1618-10 standard method. A multistep classification procedure was tested by cross-validation based on model data sets comprised of the time-averaged mass spectra also referred to as total ion spectra of commercial ignitable liquids and pyrolysis products from common building materials and household furnishings referred to simply as substrates. Fire debris samples from laboratory-scale and field test burns were also used to test the model. The optimal model's true-positive rate was 81.3% for cross-validation samples and 70.9% for fire debris samples. The false-positive rate was 9.9% for cross-validation samples and 8.9% for fire debris samples. Abstract published by arrangement with Wiley.