Collision Analysis of Safety Devices to Prevent Hazards in Safety Critical Systems

The importance of safety-critical systems is increasing, as seen with the terrible accidents recently occurring in nuclear power plants and with airplanes. To ensure the safety of those systems, system engineers should consider how to prevent system hazards during the design phase of system development. Although existing techniques such as event tree analysis and cause-consequence analysis provide various ways of hazard prevention for safety-critical systems, previous studies did not provide a solution for the situation where any two actions of hazard prevention collide. This paper suggests a collision analysis technique of safety device using fault prevention tree and resource map as a method to identify and analyze colliding actions. The proposed technique would help design robust systems to prevent hazards, and also fulfill the software requirement of safety in practical system development.