Role of Supervision Systems in Railway Safety

This paper describes how the new generation of supervision systems in the railway industry can achieve operation from display process variables to all automated control where the human just monitors the automaton. In the railway specific industry, supervision is organized in switching zones and aims to be centralized in an Integrated Control Center. These centers implement integrated and computer based systems that perform train protection, train operation and supervision. Thus railway dispatchers using supervision have their tasks considerably simplified. Although considered today as not safety critical, railway supervision systems can contribute to safety in some scenarios where an appropriate decision of a supervision operator could notably reduce the severity of accidents. That is in particular the case for residual scenarios (intervention of maintenance teams on the tracks, manual operation of trains not protected by train protection system, coupling/uncoupling, emergency requiring the stopping and evacuation of a train etc) only covered by procedure, thus requiring human intervention by a person supposed correctly informed on the state of the system, thanks to the data provided by the supervision system.