A Discussion and Evaluation of the use of Eliminative Argumentation (EA) to other leading Hazard/Risk Assessment Methodologies for the Safety (Assurance) Case for the CERN Large Hadron Collider (LHC) Machine Protection System (MPS)

Abstract

Safety Cases, also referred to as Assurance Cases, are structured arguments intended to show that a system is acceptably safe for use in its operational environment. The main role of these cases is to organize evidence about a system’s safety into a comprehensive high-level safety argument that can be understood by a range of stakeholders. Many different hazard and risk assessment techniques have been proposed for developing and representing a safety case for a system. These techniques can vary in terms of argument clarity, formalizability and error mitigation; however, evaluating and comparing these techniques is challenging as very few large-scale cases are fully open-source and available in the public domain. In this paper we demonstrate how a large-scale, open-source case study for the nuclear research facility CERN, and its Machine Protection System (MPS), can be used by the wider nuclear community to assess new and existing methodologies for risk assessment.