Evaluating the core damage frequency of a TRIGA research reactor using risk assessment tool software

Abstract

After all preventive and mitigative measures considered in the design of a nuclear reactor, the installation still represents a residual risk to the outside world. Probabilistic safety assessment (PSA) is a powerful method to survey the safety of nuclear reactors. In this study the occurrence frequency of different types of core damage states (CDS) which may potentially arise in Tehran Research Reactor (TRR) is evaluated by use of the recently developed risk assessment tool (RAT) software which has been designed and represented in the Safety Research Center of Shiraz University. RAT uses event trees and fault trees to evaluate the total final core damage frequency (CDF) through studying the frequencies of initiation events, and following their consequences has resulted in one type of the CDS. The criterion must be of the order of smaller than 1E−04 through IAEA standards for research reactors ( IAEA-TECDOC-400, 1986). Results show that the total final CDF for TRR is of the order of 10 −6, which meets the criterion of nuclear research reactor.