From risk representation to risk acceptability : how risk representation tools shape decision making

When it comes to land use planning, risk acceptability can be assessed thanks to different types of representations: FN curves, individual or societal mapping. Whatever the representation tool adopted, it has to consider simultaneously risk assessments performed by experts on one hand and risk perceptions constructed by various stakeholders on the other hand. This paper will explore how the very choice of the risk representation tool is already influencing decision makers by highlighting some risk features over other ones. After deploying a risk assessment approach on a case study following the policies from various European countries, we will underline how the decision making fits quite well with the risk representation tool used. In addition, we will show that it would have been very difficult to enforce policies with different goals by using the same risk representation tools. Consequently, the paper acknowledges that when a risk governance policy is created, the decision-makers should first define very precisely the goals of the policy they want to enforce in order to select the tool which best fits their needs.