Emergency 101 - suicide bombers, crowd formations and blast waves

Abstract

Suicide bombing has become one of the most lethal and favorite modus-operandi of terrorist organizations around the world. While various attempts have been made to assess the impact of crowd density on suicide bomber effectiveness, the specifics of the actual crowd formation and orientation of the bomber with respect to the crowd has not been examined. A virtual simulation tool has been developed which is capable of assessing the impact of crowd formation patterns on the magnitude of injury and number of casualties during a suicide bombing attack. The tool examines variables such as the number and arrangement of people within a crowd for typical layouts, the number of suicide bombers, and the nature of the explosion including equivalent weight of TNT and the duration of the resulting blast wave pulse. The goals of the analysis are to determine optimal crowd formations to reduce the deaths and/or injuries of individuals in the crowd, to determine what architectural and geometric changes can reduce the number of casualties and injuries, and what is the correlation between variant crowd densities and formations with the weight and pulse duration of the explosives? Results indicated that the worst crowd formation is street (e.g. Zig-Zag) where 44% crowd can be dead and 71% can be injured (there is an overlap of injury and lethality), given typical explosive carrying capacity of a single suicide bomber. Bus and market crowd formations were found to be the best for reducing the effectiveness of an attack, with 24% and 26% crowd in lethal zone respectively and 58% and 54% in injury zones. Simulation results were compared and validated by the real-life incidents and found to be in good agreement. Line-of-sight with the attacker, rushing towards the exit, and stampede were found to be the most lethal choices both during the attack and post-explosion. These findings, although preliminary, may have implications for emergency response and counter terrorism. The paper also discusses additional capabilities that are being developed for the model.