Basis for the Safety Approach for Design & Assessment of Generation IV Nuclear Systems - Rev 1 - 2008

This document, the first major work product of the Generation IV International Forum (GIF) Risk and Safety Working Group (RSWG), outlines the findings and recommendations aimed at guiding the R&D activities of Generation IV nuclear systems to promote safety and efficient licensing. The RSWG's mission is to establish a homogeneous and effective safety approach for the six diverse Generation IV reactor concepts. The document emphasizes the importance of integrating safety into the fundamental design rather than adding it later, leveraging technological advancements and a cohesive safety philosophy to further improve on the already excellent safety record of existing nuclear power plants.

The Generation IV Technology Roadmap identifies three specific safety goals: operational excellence in safety and reliability, a very low likelihood of reactor core damage, and the elimination of the need for offsite emergency response. To meet these goals, the RSWG has defined attributes and methodological advances necessary for Generation IV systems. Key recommendations include adopting a risk-informed approach combining deterministic and probabilistic methods, using advanced modeling and simulation to complement prototyping, and ensuring that design basis covers a full spectrum of safety-significant conditions.

The report also underscores the importance of a robust safety demonstration, using natural phenomena and physical properties to intuitively and confidently manage accident progression, and suggests practical instruments like the Objective Provision Tree and the Line of Protection to support design and assessment activities. Future RSWG activities will focus on further developing the safety framework, testing and demonstrating methodologies, and proposing necessary crosscutting safety-related R&D, in collaboration with System Steering Committees and other relevant working groups.