KR24 Use of QRA in Supporting a System Safety Case for the Victoria Line Upgrade

Abstract

AbstractIn the support of a safety case for a complex system, there is often the need to gain an understanding of the overall risk for the system and the way in which this risk will change. To do this in quantitative terms requires a system quantitative risk model. There are a number of such models available for use in the UK railway domain: for heavy rail, the Railway Safety and Standards board (RSSB) has developed a Safety Risk Model (SRM) which is available to stakeholders, and for the London Underground (LU), a London Underground QRA model (LU QRA) has been developed for each underground line which can be used in support of safety cases.This paper describes the use of the LU QRA in supporting the safety case for the Victoria Line Upgrade (VLU), which involved an upgrade to rolling stock and signalling systems. It describes the primary uses of the model, the main issues involved and the techniques developed in the course of the task.