On the Justification of a Risk Matrix for Technical Systems in European Railways

The European Railway Agency (ERA) has the challenging task of establishing common safety targets (CSTs) and common safety methods (CSMs) throughout Europe. In this context, the harmonization of risk matrices is also discussed. The purpose of this paper is to provide a formal justification of risk matrices for technical systems and the means by which compliance with legal and regulatory requirements can be demonstrated. A proposal for a standard risk matrix applicable to technical systems is derived.