An Approach to Reliability Assessment of Complex Systems at CERN

This paper presents the systematic approach Reliability Requirements and Initial Risk Evaluation (RIRE) developed and used at CERN. RIRE is a four-step procedure, which provides a framework for the experience based derivation of quantitative reliability targets for CERN’s accelerator systems. These targets are not subject to statutory regulations. RIRE shows the risks posed by a system and prioritizes subsequent, more detailed analyses, such as Fault Tree. The application of RIRE to the quench detection system of the LHC super conducting magnets is shown in this paper. From this example is concluded that RIRE is suitable for the analysis of a complex system with context dependent functions.