Performance and results of a fire probability safety analysis for the Grafenrheinfeld nuclear power plant

The Full-Power PSA for the Grafenrheinfeld 1300 MWe pressurized water reactor covering the recommended initiating events of the German PSA Procedure Guide published in October 1990 was followed up by a Fire PSA meeting the requirements of the December 1996 edition of the PSA Procedure Guide. In the meantime the Five PSA has been reviewed by the Authorized Expert, TUV Bayern. The experts agreed with the methods toed and the results obtained; they also suggested some improvements to be made in case of a revision, but these do not affect the overall results of the study. Comparing the core damage frequency caused by the initiating events of the Full-Power PSA (approx. 2.5 E-6/a) with the results of the Fire PSA (approx. 3.5 E-7/a), fire contributes approx. 12 % to the overall core damage frequency.