東京の地下 鉄の安全システムの実状と発展方向

The sharing of intelligence on disaster causes and anti-disaster measures is needed to prevent further catastrophes from occurring with no lessons learned. I conducted the analysis of the Tokyo Subway Incidents to acquire valid information to share. Based on a fault tree analysis method, I firstly put the “Damage/Casualties Occurrence” on top with the “Causes & Factors” below the top event, thus forming a tree of a disaster chain reaction. (The top event and the “Causes & Factors” are associated/interconnected with each other by the indicators AND’s and OR’s. With the tree, a case study is to start from the bottom upward to the top (“Damage/Casualties Occurrence”) with the AND or the OR determining a fact at each “gate” of the tree.) By our definition, the Subway Safety System is the one which clarifies how the two kinds of factors below should “react” to disaster damage prevention. Human factors: Station employees, train conductors and passengers in times of disaster. Material factors: Fire extinguishers, SP (sprinklers), etc. prescribed in laws and regulations. 1) It is necessary to be well aware of the fact that the System is comprised of both the human factors and the material ones. The System needs to be reviewed at drills and after disasters in terms of a disaster causal relationship. Its effectiveness is guaranteed by performance tests and system maintenance. 2) The frequencies of factor occurrences, except the “top event” mentioned above, reached 61 events (73 times) - with onetime occurrences being 53 events (53 times) and twice-or-more-than-twice ones 8 events (20 times). Specifically, the “Station Employees & Train Conductors” came out 4 times, “Passengers” 3 times, “SP” 3 times, and the five factors “Compartmentations”, “Standpipes”, “Train Windows”, “Distances” and “Intricate Routes” twice each. If the human factors are notably influential, they will be the prior issue to be considered for the development of a future subway safety system. 3) For the initial firefighting immediately after the occurrence of a fire, the human factors are unexceptionally required. This being the case, another review should be given to both the levels of individuals’ disaster preparedness awareness and the qualities of disaster drills (for handling fire extinguishers and standpipes). Challenges arisen are as follows. 1) In relation to the System, it is especially important to develop the disaster preparedness awareness of station employees, train conductors and passengers, and promote training for them. 2) For the development of the disaster preparedness awareness mentioned above, related education should be forwarded for station employees and train conductors firstly to know/understand what role each person should play in response to emergencies and what effect the human factors will have on the top event“Damage Occurrence”. 3) Given that the System is based on the public’s understanding of how important the human factors are, related training must be conducted in a varied manner. Specifically, the following will be viable: The basic training for the human and material factors, in which they will make sure they can properly act in a usual, non-emergency situation; The advanced training for the two factors, in which they will make sure they can properly act in a subway emergency, even with one or some of the factors not “functioning” well. 4) Subway passenger training should also be given. Meanwhile, it might be difficult to have many participants in the training due to the fact that anyone can be a passenger and its quantity is unlimited. Tokyo Fire Department life safety learning centers are recommended for the public to practice basic fire fighting and first aid, learn about subway-related safety systems, and experience simulated disasters to heighten their disaster response capabilities.