The Dynamics of Crowds

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The Dynamics of Crowds

• Dr. G. Keith Still
• Crowd Dynamics Ltd.

International Crowd Safety Engineers
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Who are Crowd Dynamics Ltd?
Crowd Dynamics Ltd.

• Pioneers of crowd modelling systems
• 1992 Runner up Innovation of the Year (VEgAS)
• 2000 Millennium Product (Legion)
• Regular visiting speakers UK Resilience/Emergency
  Planning College (Govt. Cabinet Office)
• Crowd Dynamics Workshops
• Consultants at Govt. Level
• Saudi Arabia, Holland, UK, Singapore, USA
• Third Generation tools
• Myriad - not one tool but many.

International Crowd Safety Engineers
3
Doorway Crowd Dynamics - Barriers

• Above left conventional doorway 40 people per
  metre per minute
• The crowd moves faster at the sides.
• Above right doorway with a barrier dividing the
  doorway
• The crowd dynamics change due to the inclusion of
  the barrier
• Barrier in the middle INCREASES the crowd flow

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Monaco Grand Prix - Station Entrance - Crowd
Crushing
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Concert - progressive crowd collapse
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Saudi Arabia - The stoning the devil Jamarat
Bridge
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Crowd Density Analysis
Crowd Dynamics Ltd.

• The Stoning the devil in Saudi Arabia during
  the Haj (annual pilgrimage to Makkah) was one of
  the most dangerous crowd environments in the
  world
• Crowd Dynamics were appointed the safety
  consultants following an accident in 2004 where
  249 pilgrims were crushed to death
• Location of the accident
• Model predicts areas of highest risk

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Infrared images of crowd leaving football stadium
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Safety in the built and complex
environmentNormal and Emergency situations
International Crowd Safety Engineers
10
Personal Security
Crowd Dynamics Ltd.

• Security isnt just the hard issues
• Buildings
• Systems
• Security is also about people
• Behavioural Based Safety
• Awareness and Strategic Analysis
• Perceptions and Human Behaviour
• Engineering and Education

International Crowd Safety Engineers
11
Discovery, understanding, control

• We build computer models and simulations to
  DISCOVER what problems may exist.
• With DISCOVERY comes UNDERSTANDING
• With UNDERSTANDING comes CONTROL
• Our simulation models were used to make safe the
  world most dangerous crowd event (2004-2005)
• Over 3,000,000 pilgrims during the Haj (Saudi
  Arabia)
• There was no margin for error
• 2005 there were no major accidents.
• .it was declared the most successful by the
  Crown Prince

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Evacuation Strategies
Crowd Dynamics Ltd.
Analysis
Planning
Implementation
Strategic detailedanalysis
Scenario Planning
Training Mgrs
Training Individuals
Data capture
Consulting
Tools Software
Communication decision support
Note-8 / Evacuation Tool
Spreadsheets Myriad
Spreadsheets Myriad
Note-8
Canary Wharf the UK Financial District
International Crowd Safety Engineers
13
Complex Office Evacuation Analysis
Crowd Dynamics Ltd.

• Simple process
• Click on exits
• Click Start
• Area per exit shown in block colour
• Test for Egress
• Congestion Analysis
• Shows where queues form (red)

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Simulation of egress shows problem
Crowd Dynamics Ltd.
Heavy use of one route (left) causing delay and
congestion
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Evacuation Strategies
Crowd Dynamics Ltd.
Analysis of complex spaces. Behavioural based
safety
International Crowd Safety Engineers
16
Simulations and models
Crowd Dynamics Ltd.
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Using Simulations
Crowd Dynamics Ltd.
Using models and simulations to develop safer
evacuation strategies
International Crowd Safety Engineers
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Site Evacuation real-time CC
Crowd Dynamics Ltd.

• Visualises incident location and safe stand-off
  
• Identifies building and routes affected
• Used in secure communications to rapidly inform
  multiple organisations
• Supports a coherent safer response by tenants

International Crowd Safety Engineers
19
Real-time CC Decision Support
Crowd Dynamics Ltd.
In seconds assess the best egress strategy
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Evacuation analysis of scenarios
Crowd Dynamics Ltd.
By testing groups of buildings evacuating at the
same time we can see the potential problems
BEFORE they hit you.
International Crowd Safety Engineers
21
Modelling New Year (London 2006/7)
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Real Time Decision Support

• ELT (Event Liaison Team) required a method to
  assess real-time flow rates and project when key
  areas would reach capacity
• We developed a model of the site using Myriad
• Created a model of arrival profiles
• We developed a method of sampling count (flow
  rates), entering that into a real-time system and
  projecting several hours advance notification of
  capacity
• Flow rates Fill Times Failure Times
  (FLOW-FILL-FAIL)
• This was used as both as decision support
  (closing off area BEFORE they fill) and an audit
  trail (in the event of an accident we can
  demonstrate due diligence for site operation)

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Developed for ELT (2006/7)
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Conclusions
Crowd Dynamics Ltd.

• New responses for new threats
• Models/simulations/training/real-time control
  systems
• Walking is an effective mode (resilience/capacity)
  for mass evacuation
• Understanding the Crowd Dynamics Behaviour
  Based Safety
• Planning needed to avoid hazards/crowd crushing
• Real-time data collection/projection
• Audit Trails
• Populations must be prepared and informed
• Real-time communication systems

International Crowd Safety Engineers