Quantitative risk analysis has become an essential decision-making tool for all industrial activities exposed to major accidents. One way of improving the benefit of quantitative risk analysis in practice is to account for the uncertainties inherent in the probability of occurrence of events and scenarios likely to occur. Indeed, in the near future, it seems inevitable that decisions will be made based on results from risk analyses with uncertainties. The bowtie method is no exception to this necessary evolution. The use of the results of this type of analysis by decision-makers requires a significant change in practice, since they lead to a probability distribution of the probability of occurrence of an event or scenario, and no longer to a simple average value that can be directly transferred to risk matrices. This article is a contribution to this predictable evolution, which raises the question of the relevance of a suitable graphical representation as an aid to decision-making. The proposed solution is a probability class-based histogram, which yield an unambiguous projection the results from a risk analysis with uncertainties onto regulatory risk matrices.
