NUKLEONIKA 2005, 50(3):105-112

IMPROVING REACTOR SAFETY SYSTEMS USING COMPONENT REDUNDANCY ALLOCATION TECHNIQUE

A. S. Habib1, H. A. M. Ashry2, A. M. Shokr3, A. I. Dakhly2

1 Department of Mathematics, Faculty of Science, El-Minufiya University, Shibeen El-koom, El-Minufiya, Egypt
2 National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo, Egypt
3 Atomic Energy Authority, ETRR-2, 13759, Abou zabal, Egypt


This paper addresses the improvements to the reliability of the safety systems of nuclear reactors using redundancy allocation technique. The study has been carried out using the Probabilistic Safety Assessment (PSA). PSA involves, among others, the use of fault and event tree tools in the evaluation of the safety system failure probabilities and the quantification of annual occurrence probability of the accidental conditions postulated in the design of the nuclear reactors. The PSA has been presented and discussed. The Egypt Second Research Reactor, ETRR-2, has been used as a case study. The failure probability of the already existing safety systems has been reviewed. The effect of the allocation of more redundant components to the existing safety systems on the failure probability of the systems has been evaluated. The event trees for two selected initiating events, from those events postulated in the ETRR-2 design, have been studied considering the allocation of more redundant components to the safety systems. The result of the study showed that further improvement could be introduced to the reliability of the Confinement Ventilation System (CVS).