The overall objective of MUSAM is to develop, validate and promote a harmonised, uncertainty-informed methodology for SA analysis and AM supporting the safe LTO of existing Nuclear Power Plants (NPPs) and the safety assessment of forthcoming reactor technologies and research reactors. The project will provide methods, data, guidance and training that enable safety analysts, licensees, Technical and scientific Support Organisations (TSOs), regulators and emergency preparedness actors to quantify how modelling, plant condition and safety system uncertainties affect predicted accident progression, safety margins, Source Term (ST) predictions, AM decisions and emergency preparedness, leading in the long-run to a step change in the way nuclear safety is evaluated and managed in Europe.

The specific objectives:

• Develop and validate a consolidated UaSA methodology applicable across representative SA analyses
• Provide a harmonized reference framework for methodology implementation.
• Demonstrate the methodology on representative SA scenarios for current WCR technologies
• Extend and validate the methodology for representative water-cooled SMR designs and SA scenarios.
• Develop best practice guidance supporting the implementation of the methodology.
• Strengthen competences of MSc/PhD students and young researchers through education and training.

Promote uptake through communication, dissemination nd engagement with regulators, TSOs and end users.

• A validated and technology-neutral UaSA methodology supporting AM, safety assessment and safety-margin evaluation across current and future reactor technologies.
• A Demonstration package supporting a decision-support framework to enable uncertainty-informed safety assessment and AM decisions.
• A validated methodology across operating Gen II LTO reactors, Gen III/III+ designs and representative SMRs.
• A best practice guidance, BPG, consisting in a practical methodological guidance and the corresponding implementation workflows to support harmonised uncertainty-informed SA analyses.
• Capacity building and knowledge transfer. MUSAM will include a European E&T package, supporting the uptake of uncertainty-informed safety assessment methodologies by the next generation of nuclear safety professionals.

• MUSAM will entail a new way to approach severe accident simulations, with a better understanding of the existing predictive capability. As a consequence, safety analysis will benefit from the insights, with implications in aspects as important as: accident management; new systems licensing; emergency planning zones, etc.
• The broadest nuclear stakeholders possible do participate in the project, from regulators to licensees passing through academia, researchers, TSOs and utilities, so that the diversity will allow to converge in a harmonized path to apply the methodology to be developed and validated in the project.
• Applications will extend from the operating fleet (Gen. II and Gen. III reactors) to the so called water cooled (SMRs, Small Modular Reactors), which will turn the methodology into a useful safety tool assisting safety enhancements with technology neutrality.
• The broad geographically and diversity spectrum stakeholders would foster the application of the methodology in Europe and elsewhere. By the activities foreseen in dissemination and communication, including open training workshops, the maximum penetration of the methodology within the Safety Community will be pursued.

CIEMAT/KIT/LGI/UNIPI/ENEN/GRS/ENEA/INRNE/EDF/Energorisk/Framatome GmbH/KTH/LEI/VMU/VTT/WUT/UNIROMA/PSI/SSTC NRS/BOKU/PHIMECA/JRC/ENSO/BEL V/WESTINGHOUSE/FRAMATOME SAS/KAERI/CRIEPI/EPRI/Amentum/CNL

Duration: June 2027– May 2030 (4 years)

Budget: 2.98 M€

Project coordinator:

Luisen.herranz@ciemat.es

Technical coordinator  

Delphine.meyer@