A methodology for assessing catastropic damage to the population and environment: A quantitative multi‐attribute approach for risk analysis based on fuzzy set theory

A worldwide discussion about catastrophic events in the chemical process industry was initiated by major disasters such as Seveso, Flixborough and Bhopal. As a result of the disaster in Basel (Switzerland), known as “Schweizerhalle,” special regulations regarding catastrophic events were set up in Switzerland. In this context a method for the quantitative evaluation of the risks associated with stationary chemical installations was developed. In the past, only one attribute for assessing the magnitude of impact, namely the number of fatalities, was considered risk analyses. In this paper a methodology for an extended damage assessment of the overall impact of an event including damage to man and animals, to ecosystems and natural resources, and to property is presented. The crucial question is how the overall impact can be represented by a limited number of indicators. Two basic questions are also important in this context: First, how can we assess and quantify the inherent fuzziness of the notion “catastrophe?” Second, how can we describe the impact by using different indicators in a multi‐dimensional way? The main aspects of this method, namely the indicator appraisal and the linking of the indicator values to a single disaster value are discussed in this paper.