ICPE hazard studies - Scenario analysis

As with the impact study, the content of the hazard study is defined in Decree no. 77-1133 of September 21, 1977, implementing Law no. 76-663 of July 19, 1976, on facilities classified for environmental protection, codified in Article L. 511-1 et seq. of the French Environment Code, and more specifically in Article 3, paragraph 5. This stipulates that a hazard study must be attached to each copy of the application for authorization, and that it must :

• on the one hand, exposes the hazards that the plant may present in the event of an accident, presenting a description of accidents that may occur, whether their cause is internal or external, and describing the nature and extent of the consequences that a possible accident may have;

• secondly, justifies the measures taken to reduce the probability and effects of an accident, as determined under the responsibility of the applicant.

This study specifies, in particular, the nature and organization of the private rescue resources available to the future operator or which he has secured to combat the effects of a possible disaster, taking into account the public rescue resources made available to the applicant.

In a previous dossier, we presented "Étude de dangers des ICPE. Identification of hazards", the analysis of existing or future installations on a site (intrinsic hazards) or hazards external to the site but which could lead to the appearance of a hazard on the site.

In this second dossier "Étude de dangers des ICPE. Analyse des scénarios", we describe the analysis and study of possible accident impacts.

Under the French ICPE Act of July 19, 1976, the operator of a classified facility must demonstrate that his activity does not give rise to any harmful consequences for the environment and human beings. It is up to the operator to describe these risks and their consequences, the measures taken to prevent them and the level of residual risk.

The aim is to calculate the consequences of any aggression to which an industrial unit may be exposed. This aggression concerns the vicinity of the unit.

There are two types of receiver to consider:

• first and foremost, the human body;

• secondly, equipment in the vicinity of the "aggressor" equipment. Equipment is not necessarily of interest to us as such, but because it can contribute, through the synergy of incidents, to modifying the initial incident, by aggravating or complicating it, by modifying the conditions and modalities of intervention...

...