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 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 – The application of – 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 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 Yuquanlu one death Fab.14, 2016 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 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 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 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/ doors Train 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 Depart the train, Depart the train, Condition of Condition of Open/close Open/close emergency emergency doors, doors, train doors&psd train doors&psd starting signal starting signal Passenger nearby Passenger nearby Emergency break Emergency break the doors the doors Emergency Condition of break door area Condition of Physical Controllers door area Physical Controllers

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 LAB OF RAIL TRAFFIC CONTROL & SAFETY Operational level

Driver Passengers nearby Safety responsibilities Human got stuck? Report to platform staffs or the driver, or Platform Staff use the stop the starting. Condition of Depart the train, Unsafe control actions that occurred Open/close emergency emergency doors, train doors&psd Start the train with a passenger trapped starting signal Passenger nearby Contextual reasons for the behavior Emergency break the doors Crowded station & No handy tool Emergency Condition of break Mental model flaws that contributed to door area it Physical Controllers No enough knowledge to cope with this situation Train door PSD Not prepared so panicked Passengers getting on or getting off Passengers are instable as volunteer Door area controllers of door system 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 Passengers

Driver Closed & locked It’s hard to get onboardClose the doors withoutStarting signal push and squeeze. Door control Signal system Peoplesystem often been kidnappedClosed & locked？ Close the by door Closedpassenger&locked？ flow Train door controller PSD controller

alarm Train door PSD Condition between train door & PSD

Pull open Passenger system Human-machine Passengers getting on or getting off interaction Role：controller Safety responsibilities  Stop getting onboard when the car is full Contextual reasons & Mental  Stop at the alarm. model Unsafe control actions that occurred  Be the last one to get on a packed car  Passengers’ mental model  Did not obstruct the closing train doors Contextual reasons for the behavior could be greatly  It s hard to get onboard without push and squeeze. influenced by passenger  People often been kidnapped by passenger flow  Hope to get home soon flow. Mental model flaws that contributed to it Passengers as controllers of  People overlooked the importance of order at rush themselves time 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 Passengers’ role

 Volunteer controllers of the door system ——the instable controller

 Controller of themselves when during transfer ——make advisable decision with crowds

 Context of interaction and of other controllers ——the crowds block interactions 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 Management level

Coordination and Communication Evening peak temporary + Interchange Management traffic policy station + Municipal Government Passengers in station + Traffic flow warning, feedback station close order - Passenger flow + + Frequency Control of station of the trains Driver Time table OCC - Emergency Traffic flow warningCondition of passenger flow Degree of - + crowdedness Station Platform staff work Station dwell time arrangement + Passenger flow control Difficulty for - passenger Passengers in station transfer Suited - - context Passenger flow not been controlled effectively. Pressure of - driver Lack of regular and efficient approach to feedback when the station/individual are out of capacity. Tidal with passenger flow 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 Suggestions

 A specific physical controller should take this safety constrain in charge. And there should be a stable feedback to monitor the gap

 More propaganda should be carried out by public education and the operation corporation not only about behaving in order but coping with emergency.

 Subway operation cooperation should use tidal control strategy and control the passenger flow if it’s beyond the capacity. 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 Changes

Longer & louder alarm

Train doors and PSDs close at the same time 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 Changes

Passenger limiting

Volunteers at peak time Lookout stage 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 Conclusion

 A CAST analysis was made and gave us some systematic suggestions.

 Passengers should be thought from different roles within subway system.

 Control structure should be designed dynamically with different passenger flow. 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

Q&A!

State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University

Email: [email protected]