1. Introduction

The stakes involved in carrying out risk analyses are becoming increasingly crucial for manufacturers. Indeed, for a given severity, an accident scenario may, depending on its probability, require modifications to safety concepts, or even, in the case of French regulations, lead to :

• refusal of operating permit (hazard study carried out as part of DAE);

• the closure of industrial sites where the acceptability of the site cannot be demonstrated in accordance with the circular of September 29, 2005;

• the expropriation of local residents following the implementation of a technological risk prevention plan (PPRT).

Assessing the probability of occurrence of industrial accidents requires an ever-increasing degree of detail, and therefore the use...