Reliability and risk assessment in the LHC and SPS machine and personnel protection systems: case studies

by F. BALDA (ST)

Thursday 6 Feb 2003, 14:15 → 15:15 Europe/Zurich

LHC Auditorium (CERN)

Safety and reliability have become crucial topics for many subsystems of the LHC accelerator. Results of Reliability-Availability-Maintainability-Safety (RAMS) studies and applications of risk analysis techniques on some of these systems are presented. We show how to implement criteria for the acceptability of risk in the engineering specification of a system, and consequences are taken into account in terms of harm to human life, damage to installations, cost and machine downtime. In particular, we discuss the application of the international safety standard IEC 61508 which fixes clear thresholds for assigning safety requirements to a system, in terms of risk, probability and frequency of failures. We review the application of methods for reliability assessment - implemented in a dedicated RAMS software package - to both machine and personnel protection systems, such as:

- systems to be designed (the LHC Access Safety System, the LHC network communication system, several safety PLC hardware configurations, the Beam Loss Monitor system),

- existing systems that might have to be upgraded (the SPS Access Safety System).