An IEC 61508 Viewpoint on the Safety Assessment of Railway Control Systems

Abstract

An article entitled “An IEC 61508 Viewpoint on System Safety in the Transport Sector” in the July 2022 edition of the Safety-critical Systems eJournal, proposed a way of thinking about the safety assessment of transportation systems that is based on the fundamental principles of international functional-safety standard IEC 61508.  Then, in a second article (January 2023), an operational example from Air Traffic Management (ATM) was used to outline how an IEC 61508 approach to safety assessment could be applied to the ATM sector.  Now, in this article, the example of a new, moving-block Automatic Train Control system, for a hypothetical Metro, is used to outline how an IEC 61508 approach to safety assessment could be applied to the safety assessment of railway control systems in general.