The Substrate Database was developed by the National Center for Forensic Science and the Ignitable Liquids Reference Collection committee of the Technical Working Group for Fire and Explosives (TWGFEX).  The Substrate Database is a compilation of headspace GC/MS data from burned and unburned materials that are common to fire scenes.  These materials may produce compounds that can interfere with the identification of ignitable liquids in fire debris.  The Substrate Database can assist the fire debris analyst by demonstrating the types of compounds and chromatographic patterns that may be produced by these commonly encountered materials.   The Substrate Database is a tool designed for screening purposes only. It does not replace the need for obtaining comparison samples to evaluate the matrix. Please note that comparison samples should be analyzed on the same instrument utilizing the same instrumental conditions as casework. Classification of any ignitable liquid residues identified within the substrate database parallels the ASTM E1618-11 and is a consensus from a committee of practicing fire debris analysts.