The first video is a friendly explanation presenting crowd crushing terms
The second video is a crowd crushing incident on NJT escalator. Please be careful as the video may be upsetting.
The third video is the lecture for this week presenting crowd safety and analysis. We will examine crowd flow and the relationship between crowd movement, ingess, circulation and egress.
Transcending Audience Safety
To understand this process, imagine a theatre about to open, where you observe people lining up on the sidewalk outside the venue. The crowd risks are now located in a specific location (the entry points) and during a specific time (prior to doors opening), it may be anticipated that the group will cover a specific area in front of the venue. When would the crowd get too big and push into the street? I suggest you base the number of people who may congregate outside be the expected number to attend event. Are you prepared?
This is first ingress issue can be simple to illustrate on a map. It shows the location of the risk, the size of the crowd, the relative risk (we typically suggest red/orange/ green to indicate these types of risk) and the time of the risk. If a series of maps/diagrams are produced for different times during an event, one can see that the risks move around the site, appear at specific locations and times for different durations. By drawing several diagrams that represent the site at different times, one can highlight the crowd risks in key areas and at crucial times. This will make it easier for event organizers to focus resources on the monitoring or management of these risks. This is a qualitative risk-mapping process, as we are visualizing the location, duration, and area of potential crowd risks. It assists in communicating risk to all that use the sidewalk and surrounding areas.
Today we will be examining.
- Potential hazards
- Crowd Flows
Let us identify the potential Hazards presented by a crowd.
- Crushing between people
- crushing against fixed structures, such as barriers.
- Trampling underfoot.
- Surging, swaying, or rushing.
- Aggressive behavior.
- Dangerous behavior, such as climbing on equipment or throwing objects.
Second let us identify the Hazards presented by a venue.
- Slipping or tripping due to inadequately lit areas or poorly maintained floors and the build-up of rubbish.
- Moving vehicles sharing the same route as pedestrians. (outside)
- Collapse of a structure which falls onto the crowd.
- People being pushed against objects.
- Objects, such turnstiles, which obstruct movement and cause congestion during busy periods.
- Crowd movements obstructed by people queuing at bars, etc.
- Crossflows as people cut through the crowd to get to other areas, such as toilets.
- Blocked egress due to poor maintenance or cleanliness
There are three phases of analyzing a crowd.
- Ingress—how they arrive and enter.
- Circulation- how they move about
- Egress how they leave the side.
Next create two maps
- normal movements
- emergency movement
By creating the maps, you can identify the best locations to manage crowd.
(quiz Answer during mapping of the site tracing routes to high density areas and implement crowd management procedures.)
Let us identify important locations on the map:
- Dependency linkages
- Means of egress.
As managers we can focus on the areas where reasonably foreseeable risks could be predicted during the planning and approval phases of the event process, and where there may be negligence, incompetence and (hence a direct link to an identified causality associated with the crowd accidents or incidents.) We outline where crowd risk analysis and safety engineering need to be introduced to prevent future problems.
Your job is to learn your Front of house. Know where all the entrances and exits are.
Where is the defined audience waiting area in the lobby? What is the head count for that area?
Inspect all access ways and aisles for maintenance and cleanliness!
Inspect all seats. Are they bolted down?
When one thinks about risk it is important to understand that there is no sure way to know when a new undetermined risk could happen on a particular day. but we can control the quantity of people, the location we manage, the duration to react and counter the risk to minimize the severity of the resulting outcomes.