The OECD Nuclear Energy Agency (NEA) continues to support international efforts to advance severe accident research, building on the outcomes of the 2024 review meeting. The 12th European Review Meeting on Severe Accident Research (ERMSAR 2026), held from 18 to 22 May 2026 in Madrid, Spain, provided a forum to assess progress and define future research priorities in this key domain of nuclear safety.
Hosted by the public research institution CIEMAT in the framework of the SEAKNOT project, ERMSAR 2026 brought together 223 participants from 27 countries and 84 organisations. As the only conference worldwide fully dedicated to this field, it continues to offer a unique platform for sharing the latest scientific and technical developments and for strengthening collaboration among experts.
Participants reviewed progress in severe accident phenomena across existing and advanced reactors, covering areas such as corium behaviour, containment performance, hydrogen risk and source term evaluation. They also addressed challenges linked to small modular reactors (SMRs), accident tolerant fuels (ATFs) and advanced designs, highlighting the need to integrate experimental data, modelling and operational experience to strengthen accident prevention and mitigation.
The NEA played an active role in ERMSAR 2026, contributing to the technical programme and supporting high-level discussions on the future direction of severe accident research. Through its Working Group on Analysis and Management of Accidents (WGAMA), the NEA continues to provide an expert-driven forum where member countries work together to develop, assess and validate technical knowledge.
At ERMSAR 2026, the NEA contributed to panel discussions on key issues, moderating a panel on expectations from severe accident R&D and contributing as a speaker to discussions on research frameworks. These discussions addressed the integration of international research efforts, data management and preservation, and the definition of priorities for future co-operative projects. They emphasised the importance of co-ordinated approaches and of ensuring that research outcomes are effectively shared and used across countries and organisations.
The discussions also underlined a central aspect of NEA activities: research is carried out by its members, who actively contribute to and benefit from the collective programme of work. This collaborative model enables the development of robust, consensus-based technical knowledge and supports evidence-based decision making in nuclear safety.
On 22 May, participants extended the discussions through technical visits, exploring advanced simulation facilities at Westinghouse/Tecnatom and research laboratories at CIEMAT.
Technical visit
Poster session
The conference highlighted that managing severe accident knowledge is not only about generating data, but also about ensuring that data are preserved, shared and effectively used to improve safety, which is a core focus of NEA activities, including within WGAMA.
The next ERMSAR edition is planned for 27-30 March 2028 in Bled, Slovenia.
