轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Exploring the systematic causes of Beijing subway PSD accident Shijie Zhang, Ph.D. student State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Outline Background and Motivation – Background Beijing subway – The application of platform screen doors – Overview of the accident Beijing subway PSD accident analysis with CAST – Physical and Operational Level – Management level – Passenger’s role as context & controller Changes & Conclusions 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Outline Background and Motivation – Background Beijing subway – The application of platform screen doors – Overview of the accident Beijing subway PSD accident analysis with CAST – Physical and Operational Level – Management level – Passenger’s role as context & controller Changes & Conclusions 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Background The Beijing Subway is a rapid transit rail network that serves the urban and suburban districts of Beijing municipality. The network has 18 lines, 334 stations[a] and 554 km (344 mi) of track in operation. The subway is the world‘s busiest in annual ridership, with 3.41 billion trips delivered in 2014, averaging 9.2786 million per day, with peak single-day ridership reaching 11.5595 million. “Beijing 2015 and "twelfth five-year" period for national economic and social development statistical bulletin”. Beijing Municipal Statistics Bureau. 2016-02-15. Retrieved2015-02-18 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY People fell off platform From “House of cards” S02 Beijing subway, 2016 Time line station consequence Jan.28, 2016 line 1 Yuquanlu one death Fab.14, 2016 line 2 Dongzhimen one death Fab.28, 2016 line 1 Yuquanlu one death Mar.2, 2016 line 1 Wanshoulu one death 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY The application of platform screen doors(PSDs) The purpose – Safety: Train piston wind & Fall off platform – Energy conservation: Air condition – Prevent suicide The system become more complicated 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY The gap About 300mm in width Hazard: Train start with people between train doors and PSDs. 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Historical accident 2.Could not get 3.PSDs already closed onboard because it’s crowded 1.Run to the train when doors were closing 4. The man got killed Shanghai metro line 1, Nov.6, 2007 by the departing train 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Overview of the accident The location Accident spot On November 6, 2014 at 18:57 Beijing subway line 5 Huixinxijie Nankou station A woman fell out the train and got trapped between the train door and the PSD and train departed The women died in hospital at 20:20 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Passenger volume at peak APEC 11.06 Beijing subway has serious “tidal phenomena”. Huixinxijie Nankou —— Important interchange station 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Outline Background and Motivation – Background Beijing subway – The application of platform screen doors – Overview of the accident Beijing subway PSD accident analysis with CAST – Physical and Operational Level – Passenger’s role as context & controller – Management level Changes & Conclusions 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Train & station system Technical system Human Signal system Driver Train door PSD Platform controller controller staff Train doors PSDs Passenger Hazard：Train start with people between train door and PSD. Safety constrain：There must be no person between train doors and PSDs when the train start. 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Measures Driver’s check Plate on PSD Emergency tools Handle on PSDs Platform staff’s assist 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY The Proximate Events Train Platform other Time Victim PSDs Driver doors staff passengers start to 18:57 close fell out of train start to close got trapped closed closed looked for didn't find forgot to staffs and the check the gap emergency emergency tools started the train got hurt stopped the train sent to hospital 20:20 died in hospital 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Safety Control Structure Driver Human got stuck? Emergency Platform Staff Depart the train, Condition of Open/close PSDs doors, emergencey starting signal Open/close Emergency break Passenger nearby train doors Emergency break Condition of Signal system door area Open Condition of Condition Open/close Enable train doors of PSD PSD Condition of door area Open/ Train doors Open close /close PSDs Train door GAP PSD controller controller Condition of train doors Condition of PSDs 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Physical Level No sensor in the gap. Driver Closed & locked Starting signal Deficiencies in system design: Close the Signal system doors Role: Controller Safety responsibilities (requirements) Release break only if both train Safety constrain not doors and PSDs are closed&locked. Condition between Door control train door & PSD allocated to a controller. system Closed & locked？ Close the doors Closed&locked？ Train door controller PSD controller Role: Role: PSDs closed, no Controller Controller Safety responsibilities(requirement) Safety responsibilities(requirement) equipment can detect Start to close the door specified time Start to close the door specified time Stop door with residence over 150N Stop door with residence over 150N Unsafe Interaction gap. Plate obstruct Sequence : Train doors alarm Train doors Gap PSDs close after PSDs. Passenger system Passengers getting on or getting off 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Physical Level Driver Closed & locked Starting signal Close the Signal system Deficiencies in system design: doors Role: Controller Safety responsibilities (requirements) Release break only if both train doors and PSDs are closed&locked. Condition between Assist: Drivers may neglect Door control train door & PSD system Closed & locked？ Close the doors Closed&locked？ the check especially on rush Train door controller PSD controller hour with the assist of Role: Role: Controller Controller Safety responsibilities(requirement) Safety responsibilities(requirement) equipment. Start to close the door specified time Start to close the door specified time Stop door with residence over 150N Stop door with residence over 150N Plate obstruct alarm Train doors Gap PSDs Passenger system Passengers getting on or getting off 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Operational level Driver Safety responsibilities Supervise passenger transfer, ensure safe starting conditions Driver Unsafe control actions that occurred Human got stuck? Start the train with a passenger trapped Platform Staff Contextual reasons for the behavior Condition of Depart the train, emergen Open/close emergency doors, train doors&psd cy In rush hour, driver worked under the starting signal Passenger nearby Emergency break the doors pressure of the busy timetable; Emergency Condition of Equipment provided unreliable assist. break door area Mental model flaws that contributed Physical Controllers to it The driver was too dependent on Train door PSD preventing equipment; Passengers getting on or getting off Neglect the importance Door area 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Operational level Dysfunctional Interaction Driver Passengers cannot found platform Human got stuck? staffs to report the emergency Platform Staff Reason: The platform was crowd, Condition of Depart the train, vision was blocked and environment Open/close doors, emergency emergency train doors&psd was noisy. starting signal Passenger nearby Emergency break the doors Platform staffs find it hard to Emergency Condition of break supervise all the doors. door area Passengers cannot reach emergency Physical Controllers tools. Reason: No handy emergency Train door PSD break or emergency call device. Passengers getting on or getting off Cannot get to tools nearby due to Door area the crowds. 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Emergency button Emergency button on platform Emergency button upon train doors Only set on 2 middle doors of each carriage Accident spot Car 1 C 2 C 3 C 4 C 5 C 6 Platform track Platform Platform track 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY LAB OF RAIL TRAFFIC CONTROL & SAFETY Operational level Driver Driver Human got stuck? Human got stuck? Platform Staff Platform Staff Condition of Depart the train, Depart the train, Open/close emergency emergency Condition of doors, Open/close train doors&psd doors, starting signal train doors&psd Passenger nearby starting signal Emergency break Passenger nearby the doors Emergency break the doors Emergency Condition of break door area Condition of Physical Controllers Physical Controllers door area Train door PSD Train door PSD Passengers getting on or getting off Passengers getting on or getting off Door area Door area 轨道交通控制与安全 国家重点实验室(北京交通大学) STATE KEY