Fire Risk Assessment and Its Economic Loss Estimation in Tehran Subway, Applying Event Tree Analysis

Subway system is one of the critical infrastructures in a society. In economic optimizations of risk control measures, valuing the loss of life and other financial losses in terms of money on the other hand, could influence the optimal investments in safety. The purpose is to contribute to the implementation of HSE in the transportation system. In this research, a fire risk assessment along with its economic loss estimation in the Direct Current (DC) trains and rectifier substation (RS) of Tehran subway is implemented. The number of fatalities, the extent of damage on the train equipment, etc., is then calculated in monetary unit.By using Event Tree Analysis (herein ETA), after identification of initiating events through observation, interviews, and evaluation of documents, event tree was constructed for each of them and the probability of multiple scenarios were computed.The scenario with the highest probability of fire in RS, including increased heats in the RTU panels generate a loss of at least 730 Million Rials. Accordingly, the minimum and maximum economic loss caused by fire on DC trains is minimum 510 and 1230 Million Rials, respectively. Given the findings of this study, the financial and human life risks, along with all tangible and intangible losses, which is considerable, the relevant managers must compare investments in safety, with the decrease of calculated economic risks as a result of fire accident in Tehran subway.