Crowd Flow Considerations - LAEOGCrowd Flow Considerations Flow Rates (Rates of Passage) The rates...
Transcript of Crowd Flow Considerations - LAEOGCrowd Flow Considerations Flow Rates (Rates of Passage) The rates...
Crowd Flow
Considerations
Flow Rates (Rates of Passage)
The rates are typically expressed as the number
of people for each metre of width who can pass
a given point per minute (people per metre width
per minute).
Such calculations will be relevant in respect of:
‒ Calculation of ingress capacity/time
‒ Circulation of persons around the event/venue
This will be particularly relevant in respect of
egress and evacuation capacity calculations and
times
What factors do you consider relevant in
determining appropriate flow rates for your events?
Type of event
Dynamics of crowd
Nature of surface, slopes/steps, obstructions
Profile of audience (include child/mobility considerations)
Destination/objective
Crowd density
Bags and equipment
Safety management
Reaction times
Distance to travel
Fatigue
Historic behaviour
Uneven distribution
Lack of familiarity
Lighting
Traffic
Weather
NORMAL OR EMERGENCY This is not intended to be an exhaustive list
Three major influences
density of crowd (numbers/square metre)
speed of movement
number & widths of exits (including consideration
of pinchpoints outside of the venue/site)
What guidance may be applicable to rates of passage?
Guide to Safety at Sports Grounds
The entry capacity is the number of people who can pass through all the turnstiles or entry points serving either the whole or one section, within the period of one hour. For the purpose of calculating the entry capacity, the upper limit is set at 660 persons per turnstile (or other entry point) per hour
The rates are expressed as the number of people for each metre of width who can pass a given point per minute (people per metre width per minute).
On all stairways and on all routes within seated accommodation (including gangways, concourses and ramps) the amended upper limit is given as 66 spectators per metre width per minute.
On all other routes (including within standing accommodation) the amended upper limit is stated as 82 spectators per metre width per minute.
These values should not be used to calculate safe egress rates – they are upper limits only. At best they give a rough guide for assessing evacuation but there are hidden implications that need discussion.
What guidance may be applicable to rates of passage?
Fire Safety Risk Assessment (Open Air Events and Venues)
The capacity of an escape route is determined by the rate by which people pass along the route during each minute of the defined escape time. The following are the suggested rates of passage for open air parts of venues:
On all routes within seated accommodation (including gangways and ramps) and stairways – 73 persons per metre per minute
On all routes in other parts of the event or venue (including within standing accommodation) – 109 people/metre/minute
Speed of movement
This tells us that we may
typically expect that
when a moving crowd
reaches a density of 4
persons per square
metre speed of
movement slows
dramatically.
In confined space this
can be a significant
safety concern
Remember 3 Fs
Flow
Fill
Fail
What do we mean by egress time?
Egress - time taken, under normal conditions, to
leave viewing area to enter free flowing exit system
- normally 8 minutes.
Contrary to some misunderstanding this does not
always imply emptying a sports ground.
This is typically 8 minutes for sports grounds
Telstra Dome - Melbourne
Telstra Dome - Melbourne
Station
Telstra Dome - Melbourne
Background
Up to 55,000 spectators
Raised external
concourses
Approx 80% wish to use
rail/tram systems
Aerial walkway is only
option to access
rail/tram station
Steps at far end to
access station
Swedbank Arena Stockholm
Swedbank Arena Stockholm
Shopping Centre
Robbie Williams, Knebworth (2003)
The ‘Bridge of Despair’
3 consecutive nights
125,000 per night
40m of arena exit width leading to 15m gap – classic pinch point.
Not enough lighting
Illegal traders blocking footpaths
‘Mass’ egress from arena (‘push’)
Majority of audience departing to car parks via this route
How can Design, Information,
Management help on next two nights?
So how can it go wrong?
Background
Free electronic dance event at former
rail yard
Capacity of site around 250,000 though
many more expected (reports suggest
up to 2 million)
Access from East and West via tunnels
Ingress/egress agreed via one ramp,
although a second is available but
closed
Reports suggesting that venue was full
which caused ingress to be halted
Flow into tunnels continues increasing
density and some attempt to leave
Progressive collapse/crush results in 21
deaths and 500+ injured
24 July 2010
Love Parade, Duisburg,
Germany
So how can it go wrong?
Background
Last day of National Celebration
featuring traditional boat races
(420 boats)
Hundreds of thousands in
attendance (estimates suggest 2
million)
Tens of thousands on bridge
connecting to Diamond Island
where concert and exhibition
were being staged
Reports that bridge was
collapsing
Progressive crowd collapse
351+ dead, hundreds injured
23 November 2010
Water Festival, Phnom
Penh, Cambodia