Computational study on toxic gases released from compartment fires suppressed with halogenated agents

The evolution of toxic gases in the hot layer of an enclosure fire is simulated by a batch perfectly stirred reactor model using the SENKIN program from the CHEMKIN distribution package. The initial species composition was obtained from experimental data both for slightly underventilated and highly underventilated conditions. The formation rates of toxic gases were studied using a comprehensive kinetic mechanism, including the GRI 3.0 submechanism representing hydrocarbon oxidation, the National Institute of Standards and Technology (NIST) hydrofluorocarbon mechanism and the NIST CBrF3 and CF3I inhibition mechanisms for the initial mole fractions of CBrF3 and CF3I ranging from 0.5 to 5.0%. An analysis of modeling results, including the prediction of the equilibrium concentration, provided important insight into the effects of adding CBrF3 and CF3I on the formation of toxic gases in the hot layer. Sensitivity analysis was performed under the highly underventilated conditions, leading to the identification of the chemical reactions that have the most significant influence on the formation of toxic products