The German regulatory guide for nuclear power plants demands plant specific Probabilistic Safety Analyses (PSA) including External Events. In 2005, a new Methodology Guideline (Methodenband) based on the current state of science and technology was released to provide the analyst with a set of suitable tools and methodologies for the analysis of all PSA events. In the case of earthquakes a staggered procedure is suggested which requires a probabilistic analysis only for those nuclear power plants with an intensity for the design basis earthquake above I_(qbe) > 6. For earthquake intensities I_(DBe) between 6 and 7, a reduced analysis is possible. For earthquake intensities I_(DBe) above 7, a full scope analysis is mandatory. In Germany the seismic hazard curve is determined as a function of the intensity of the earthquakes. Compared to a procedure suggested in the Methodenband, a more realistic procedure to implement the hazard curve in a seismic PSA by using realistic site specific response spectra is presented, as well as the procedure to consider these spectra in the fragility analysis. Also an approach for the reduced analysis will be presented. Additionally, experiences from performed seismic PSA are discussed.
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