SAPIUM a systematic approach for input uncertainty quantification

Uncertainty assessment is a key step in nuclear applications to ensure that a system cannot move towards unsafe conditions. This topic has already been addressed by several OECD/NEA projects such as UMS or BEMUSE. However, if uncertainty propagation methods have now become mature for industrial applications, the input uncertainties quantification on the physical models still requires further investigations. It is precisely in this context that the SAPIUM project has been proposed in order to reduce as much as possible (or at least better understand) the user-effect observed in the previous PREMIUM activity that was a first attempt to analyze available methods to handle this issue. The underlying idea of the proposed work is not to focus on method benchmarking but on the construction of a clear and shared systematic approach for input uncertainty quantification as it is already addressed in industries and RandD for related topics. The main outcome of the project is a first good practices document that can be exploited for safety study in order to increase the agreement among experts on recommended practices as well as on remaining open issues for further developments. End users are therefore the developers and the users of BEPU methodologies, as well as the organizations in charge of evaluating them. Since it is an on-going activity, this paper describes the general content of the SAPIUM activity. All the details of the contributions will be available in the final document that will be issued in 2019.