Accidents in petrochemical plants and oil refineries are quite destructive, due to the high reactivity of chemicals involved in them. An accident that occurred in the Texas City refinery, on March 23rd 2005, consisting on a vapour cloud explosion (VCE) that followed a gasoline release and caused 15 deaths, has been studied in terms of people vulnerability to overpressure and thermal radiation. With this aim, simple models (TNT, TNO Multi-Energy, BST) have been used in order to evaluate the effects of the explosion.Moreover, a thermal radiation model was used to estimate the damage caused by the heat released as consequence of the explosion. Finally, the Probit methodology was used to evaluate the vulnerability of persons. Although differences between the data derived from each of them existed, they all reproduced actual damages with a reasonable accuracy. The results reached let us say that the TNO and BST models predict with a reasonable accuracy the effects of the explosion that occurred. Furthermore, the use of simplified empirical models can be used for risk assessment