Human Error Modes and Their Analysis in Centralized Railway Traffic Control

Human behaviour and human errors are important in all transportation systems because they can lead to situations with high risk and loss of life and goods. Although in many transportation systems highly dependable technical subsystem ensure the core safety, human participation cannot be entirely avoid. In the railway transportation sector, the interlocking (control-command signalling, CCS) subsystems is responsible for the primary safety, and mainly for operational issues human operators play an important role during the non-safety oriented commanding; however in case of the partial or total failure of the interlocking subsystem, human operators get the tasks of maintaining the railway traffic, thus they get safety critical responsibility in such instances. As human (operator, traffic controller or signaller) behaviour is important in the railway traffic, there is a need for a detailed analysis of the error modes and their consequences in order to be able to design such a system in which the probability of such errors is reduced to a tolerable level. In this paper we present the main error modes for human operators, summarizes the main analysis techniques and show, how TRACEr method can be used for railway signallers.