System for investigation of railway interfaces [SIRI]

The purpose of this paper is to present the results of the application of a system approach known as SIRI to find the missing risk control measures between the duty holder organisations in UK railways. The need for this type of approach was described in 2006[22]. The framework was applied to assess the adequacy of standards to regulate the duty holder organisational interfaces covering several signalling facilities like the lockout protection system, ABCL types of level crossing, permissive working operations, axle counters and train detection systems. The author found that group thinking bias is a major concern in the setting of standards and group decision making process has an adverse impact on intended safety outcomes.