Probabilistic Safety Assessments (PSAs) in Germany have essentially been conducted in the framework of recurrent Safety Reviews (SRs). Besides, probabilistic investigations have also been submitted and reviewed in the usual regulatory procedures. Significant safety relevant insights have e.g. been gained from the Human Reliability Assessment (HRA) in the context of Low Power and Shutdown (LPS) PSAs whose performance has been launched by the regulatory body. In this paper major insights and results together with the practical outcome particularly from Human Factor (HF) and safety relevance points of view are described. Thereby, general key issues on HRA as well as substantial insights and conclusions derived from LPS HRAs are addressed. Further, a specific example with respect to the design and review of a complete set of operating procedures specifically dedicated to the shutdown operation is illustrated by outlining the general approach as well as the overall outcome achieved. Finally, conclusions are drawn regarding the relevance of probabilistic investigations, the appropriateness of a symptom oriented proceeding related to shutdown operation and the potential of utilising an advanced HF methodology.

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