Severe accidents in Sodium Fast Reactors: Safety Study Approach, Prevention and Mitigation by Design is the unique presentation of the research work from the Sodium Fast Reactor Severe Accident team at CEA. Focusing on in-core and out-core severe accident phenomena, this book analyses severe accident scenarios and mitigation, related calculations and tools, and key outcomes from the important experimental programs. This book describes the state of the art on severe accident research which will help to inform and direct further pre-conceptual Generation IV SFRs. Lessons learned from the pre-conceptual phase of the French ASTRID project are highlighted alongside different approaches to demonstrate the robustness of the design and evaluation of severe accident consequences. To support the demonstration of concepts explored, a special section dedicated to calculation tools and their validation will offer readers a unique set of tools to guide and inform their own research work. Readers will gain a deep understanding of methodologies to illustrate approaches as well as an overview of safety approaches from key countries, based on the editor’s rich international collaboration.