Focus areas for the regulatory review of the probabilistic safety assessment of seismic events

An abstract of a technical presentation presented at:
Nordic PSA Conference, Castle Meeting
Swedish Radiation Safety Authority (SSM)
Stockholm, Sweden, April 10th – 12th, 2013

Prepared by:
Smain Yalaoui
Probabilistic Safety Assessment & Reliability Division (PSA&RD)
Canadian Nuclear Safety Commission (CNSC)
Ottawa, Ontario, Canada.

Abstract

This presentation will highlight the focus areas for the regulatory review of the probabilistic safety assessment (PSA) of seismic events. An overview of the Canadian Nuclear Safety Commission (CNSC) regulatory standard S-294 Probabilistic Safety Assessment for Nuclear Power Plants will be presented with an emphasis placed on the requirements regarding the treatment of external events, as well as its footnote, that allows for alternative analysis methods. Alternative methods for assessing the seismic events will be presented with a brief description of questions that can be answered by each respective method. Following this, a brief history of the assessment dating back to the early 1980s, of the seismic events by Canadian Licensees will be provided.

Also, the presentation will describe specific focus areas, as well as some of the challenges for the regulatory review of the PSA for seismic events. The high level and supporting requirements for the preparation of the seismic PSA (SPSA), as well as the seismic margin assessment (SMA) given in the American Society of Mechanical Engineers Standard (ASME-ASME/ANS RA-Sa-2009) provides a good basis for regulatory reviews.

The presentation will conclude with a high level discussion about the technical challenges specifically relating to the review of fragility calculations and the seismic PSA logic model.

To obtain a copy of the abstract's document, contact the CNSC. When contacting the CNSC, please provide the title and date of the abstract.