Identification of fire gases in early stages of fire in laboratory scaled and full scale fire experiments

摘要

A series of reduced scale emulations of standard fires in a 2 m3 enclosure have been developed for studies at laboratory scale enabling useful comparison and correlation with full scale EN54/7 and UL268 test fires. This makes study of standard test fire conditions and products substantially more accessible. The reduced scale test fire emulations have smoke obscuration characteristics matched to the fire standards and show acceptable matching of experimental CO levels Sensor, fire detector, and analytical studies have been carried out on test fires in the 2 m3 enclosure and in a full scale test room. Protocols were developed for capture of gas and vapours from fires on absorbent media and their subsequently desorption and analysis by GC/MS techniques. A data set of GC chromatograms has been generated for full and reduced scale test fires and for a number of non standard fire or false alarm related process including overheating of cooking oils and toasting bread. Analysis of mass spectrometry ion fragmentation spectra has been carried out and a wide range of products identified. Products occurring for a range of different fires include propene, benzene, and some polyaromatics. The value of the scaled test fire emulations has been demonstrated by monitoring response of a range of sensors, detectors and instruments including electrochemical gas sensor, experimental and conventional light scattering smoke detectors, and ion mobility measurement equipment (FAIMS). The study has provided information on fire characteristics and products to inform future research and development on fire detection technologies.