PROBABILISTIC SAFETY ASSESSMENT OF LEVEL CROSSING SYSTEM IN JAPANESE RAILWAY

摘要

Train protection systems in Japan such as signaling systems and level crossing protection systems have been mostly developed as upgrade of individual subsystems and post-accident measures. However, due to the introduction of advanced systems using information technology as well as the limitation of resources for safety in these days, the importance of prior assessment of railway safety as a total system is increasing for risk management to take efficient measures without any degradation of present safety level. In this paper we discuss a method for probabilistic assessment of the safety of train system with the aim of efficient and effective risk management for Japanese railway system. We describe event tree analysis and assessment of the sequences from trigger events to accidents thorough the failure of protective systems including human actions. Then, we discuss the effectiveness of this method by a simple example of Japan's conventional level crossing system with an obstruction detector.