Integrated deterministic and probabilistic safety assessment: concepts, challenges, research directions

In the Strategic Research Agenda (SRA) of the Sustainable Nuclear Technology Platform (SNETP) of the European Union, issued in May 2009, significant relevance is given to the safety of current and future Light Water Reactors. Traditionally, regulation of design and operation of nuclear power plants have been based on deterministic analysis methods to verify criteria that assure plant safety in a number of postulated design basis accident scenarios. These criteria also allow identifying which plant Structures, Systems and Components (SSC) and activities are important to safety. Design, operation and maintenance of these 'safety-related' SSC and activities are controlled through regulatory requirements. Compliance with the evolving regulatory requirements will require innovative deterministic and probabilistic approaches of safety assessment for the existing nuclear power plants. In this respect, a related medium-term challenge explicitly mentioned in the SRA is to combine the use of deterministic and probabilistic methodologies for safety assessment. In this context, the lecture will introduce the concepts of Integrated Deterministic and Probabilistic Safety Assessment (IDPSA), and the related issues and challenges