The storage of dangerous substances is a high risk procedure: a historical analysis revealed that 17% of the
major accidents associated with the chemical industry are related to this process. When a storage facility
is designed, the investment in safety is not always optimal. The safety measures that are applied are
sometimes redundant or ill-maintained. One way to improve safety in a storage facility would be to take
advantage of the fact that dividing the mass of dangerous substance results in less catastrophic accidents.
In this paper, we present a new method for optimizing the design of storage plants and minimizing the
risk by calculating the ideal number of tanks and improving the way in which money is invested in safety.
This is achieved by redefining how to estimate risk and by applying the principles of mathematical optimization
to quantitative risk analysis. The method is explained step by step. We also present two case
studies and a validation of the method using risk analysis software and iso-risk curves.