A computational fluid dynamics (CFD) model has been developed to simulate vapor cloud explosions (VCEs) of interest to the petrochemical industry. The model uses a reduced combustion model based on flame speeds that are correlated to the environment involved in the explosion. Simulations of an idealized explosion scenario are carried out and compared with experimental results for the same configuration. A porosity model used to represent small-scale objects is evaluated for grated decking commonly found in petrochemical facilities. Finally, computations using the reduced combustion and porosity models are performed for a typical offshore module and compared with experimental data. Both sets of simulations compare well with the experimental data. (C) 2001 Elsevier Science Ltd. All rights reserved.