A 1D plane, cylindrical and spherical numerical model was developed for estimating the thermodynamic and the dynamic state of the boiling liquid during a boiling liquid expanding vapor explosion (BLEVE) event. The model predicts, simultaneously, the flow properties of the expanding two-phase flashing mixture and its surrounding air. The possible presence of a shock wave formed by the fluid expansion through the air is accounted for in the model. Model predictions of the shock wave strengths, in terms of TNT equivalence for the various coordinate systems, were compared against those obtained by simple energy models. As expected, the simple energy models over predicts the shock wave strength. However, the simple model which accounts for the expansion irreversibility, produces results which are closer to current model predictions. For the 1D plane case the model simulates a BLEVE scenario in a tunnel, whereas for the spherical case the more realistic BLEVE scenario in free space is being studied.