The study found that the ability for the zNose to detect small amounts of vapor with the sampling technique used was limited. Gasoline, which contained the lightest vapors, could not be detected after 15 minutes with an initial quantity of 10 ml. Kerosene could be detected for a slightly longer time than diesel fuel (5 ml). Overall, the sensitivity was too poor to be of value in situations where only a small amount of ignitable liquid remains at the scene. Heating the fire debris would improve the sampling method; however, matrix effects would still require evaluation. Major problems found were the repeatability and nature of the sampling method. Also, the zNose cannot be used as a confirmatory technique for ignitable liquid analysis of fire debris. It is more suitable for confirming the composition of a known sample or samples with a less complex mixture or background matrix. There is still a need for a portable method that can analyze accelerants. The testing involved developing and optimizing the instrument parameters for ignitable liquid detection and identification; investigating the repeatability of the instrument and reviewing sensitivity; assessing the instrument with simulated fire debris; and evaluating the viability of onsite use. The description of testing methods and materials addresses instrumentation and reagents, method development and optimization, analytical performance, target compound identification and evaporated samples, and background interference products. 4 tables, 3 figures, and 16 references