A Risk Management Model of Urban Areas near Ammunition Storage

According to safety standards - buildings, civil facilities and heavily used routes can be located at Inhabited Building Distances (IBD) that are termed only as separation distances. Minor injuries and unstrengthened buildings damage not exceeding five percent of their Reinstatement Value are expected. Indirect consequences of Ammunition and Explosives explosion event are not considered at all in the standards. In contrary, safety demands for cases where explosion of Ammunition or Explosives is initiated or caused by hostile activities must be much greater than IBD. In order to prevent casualties or injuries to the public they should be either protected, or being moved beyond a safety distance,
much greater than the IBD. The standards usually take the low marginal probability, i.e. 10-6 per annum, and by that assume that accidental events rarely occur. Risk expectancy gives some legitimacy for these relatively short distances. On the other hand, in a circumstance where the probability of an accidental explosion is greater, and ammunition is located near urban areas, the standards might be risky and inappropriate. A risk management model for the analysis and assessment of risks encompassing physical and economic consequences is proposed. Using DDESB- TP14-SAFER methodologies and
knowledge, the model estimates a conversion between protective measures and different ammunition quantities vs. IBD for a given site data. A case study was carried out for a given town and a highway located at a permitted IBD of less than 1,000 meters from all kinds of PES (Potential Explosion Site): open storage or an earth covered magazine which contains 100 tons of Net Explosive Weight of HD (Hazard Division) 1.1. The study elucidates that under the conditions given for Israel's urban area and building standards, protection of the exposed site must be upgraded according to Israel Home Front Command, WBDG, FEMA recommendations, i.e. window strengthening, and to consider updating IBD formulae.