Smartlock 400 - a case study of high integrity product safety assurance

The presentation provides a high level overview of the safety assurance activities undertaken for, and the issues arising from, the introduction of the Alstom Smartlock 400 interlocking into the UK to its current status in revenue service, following a successful period of pilot running. The presentation provides a brief introduction to the concept and a system overview of the Alstom Smartlock 400 interlocking system. The presentation follows the safety assurance process from the development and assurance of the individual sub-systems to their integration into the overall Smartlock 400 System. The issues associated with the application of ISAs for the sub-systems and system to the release of the UK generic application safety cases are explored and summarised as lessons learnt. The case study finishes by briefly reviewing some of the ongoing issues that a modern high integrity product like Smartlock 400 will be subject to, in order to maintain its approved safety assurance status.