Compartment fire experiments were performed using either natural or overhead forced ventilation to assess the effect of ventilation on the compartment fire environment. The ventilation rate was varied by changing the vent size in natural ventilation tests and mechanically in forced ventilation tests. Three fuels were used: diesel fuel, wood cribs, and polyurethane slabs. For naturally ventilated fires, it was noted that the vent size and geometry had a significant impact on the vertical temperature and oxygen concentration profiles. Both the temperature and oxygen concentration measurements were representative of two-layer environments. However, in terms of oxygen concentration, forced ventilation fires resulted in a well-mixed compartment regardless of the ventilation rate. In contrast, temperature measurements showed either a two-layer or linear variation with respect to compartment height, depending on the scenario. These results defy the conventional assumption that compartment temperatures and gas concentrations have the same vertical distribution. Furthermore, these results identify the need to go beyond the classic twolayer paradigm. In addition, reduced oxygen concentrations at the flame base resulted in reduced mass loss rates. The relationship between these burning rates and the oxygen concentration at the flame base was examined, and a correlation was developed. The results show that temperature and flashover potential assessments based on furniture calorimeter data may be significantly overestimated.

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The development of empirical correlations for major species yields in compartment fires has become an important priority due to the inability to calculate these quantities from first principles. Studies of simplified upper layer environments have shown that major species production rates can be correlated with the equivalence ratio in what is known as the Global Equivalence Ratio concept (GER). Due to the simplification in these past experiments, it was not known if the GER concept was valid for compartment fires. Therefore, there was a need to determine if correlations existed between major species yields and the equivalence ratio for actual compartment fires.A 2.2 m 3 test compartment was used to investigate the burning of four fuels (hexane, PMMA, spruce and flexible polyurethane foam) in compartment fires. The test compartment was specially designed with a two-ventilation path system which allowed the direct measurement of the plume equivalence ratio (the ratio of the fuel volatilization rate to the air entrainment rate normalized by the stoichiometric fuel-to-air ratio).Empirical correlations between the upper layer yield of major species and the plume equivalence ratio were shown to exist. The results reveal that the production of CO is primarily dependent on the compartment flow dynamics (i.e., the equivalence ratio) and upper layer temperature. The correlations developed in the compartment fires are qualitatively similar to those developed by Beyler for simplified upper layer environments. However, quantitative differences exist and can be explained in terms of temperature differences in experiments.

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