The Working Group supports improved uses of Probabilistic Safety Assessment (PSA) in risk-informed regulation and safety management through the analysis of results and the development of perspectives regarding potentially important risk contributors and associated risk-reduction strategies. The Working Group addresses PSA methods, tools, and data needed to provide this information.

The main objective of the Working Group on Risk Assessment (WGRISK) is to advance the PSA understanding and to enhance its utilisation for improving the safety of nuclear installations, for improving the operation and the design of nuclear installations and for increasing the regulatory effectiveness through risk-informed approaches. In order to achieve this objective, the Working Group:

1. Reports to the Committee on the Safety of Nuclear Installations (CSNI) and assists that Committee with its work.
2. Constitutes a forum for exchange of information and experience related to risk assessment in NEA member countries. This exchange is not only limited to technical discussions on questions regarding risk analysis approaches, results, insights, applications and interactions with other disciplines and analysis techniques, but it shall also include identifying and prioritising important issues requiring additional research.
3. Prepares technical reviews (such as state-of-the-art reports, technical opinion papers, compilations of ongoing efforts, comparison studies etc. as appropriate) of work in all phases of risk assessment to assist further developments and the application of PSA in risk-informed decision making. This work will be done in task groups, whose work will be organised in a project-like manner with outcomes and milestones.
4. Sponsors specialist meetings and workshops to further its objectives.
5. Collaborates with or assist other CSNI working groups, the Committee for Nuclear Regulatory Activities (CNRA) and other NEA bodies on request. In particular, the WGRISK collaborates with other bodies such as the Working Group on on Integrity and Ageing of Components and Structures (WGIAGE) and the Working Group on External Events (WGEV), where those two bodies provide characterisation of seismic and other external hazards, and the WGRISK assesses the risk consequences. The Working Group also co-operates with other international organisations, aiming among others to avoid duplication of effort.