Development of a framework of safety goals for nuclear installations and its application in Germany

The International Atomic Energy Agency has started a few years ago a project to enhance the existing framework for safety goals for nuclear installations and currently is finalizing a publication aimed to provide guidance for a more holistic approach to establishing and utilizing safety goals for nuclear installations. The intention was to develop a more consistent and holistic framework for safety goals that would be composed of a hierarchical structure of qualitative concepts (e.g. defense in depth, various safety requirements) and quantitative risk metrics. The safety goals should be technology neutral at the higher level and should cover both normal operation and accident conditions as well as the risk to workers, public, and the environment. In the paper the development of a hierarchical framework for safety goals is described including a methodology to derive lower-(more technical) safety goals from the higher goals. Moreover a process for assessing the degree of compliance with the safety goals and their consistent use is provided. As an example the developed framework is applied to the German regulatory framework for nuclear installations but focused on nuclear power plants.