Allocation of safety integrity requirements for railway signaling applications

摘要

A systematic methodology to determine safety integrity requirements for railway signaling equipement,taking int account the operational enivronment and the arichitectural design f the signaling system,is presented.At theheart of this approach is a well-defined interface between the operational environment and teh signaling system,resulting in clearlydefinedrepsponsibilities for the railway operator and the supplier.from the safetypoint of view this interface is defined by a list of hazards and tolerable hazard rates associated with the system.