Evacuation simulation
model
Very Short Description:
Versatile model for predicting the evacuation
of crowds
which may be used in a large variety of situations
Modeler(s), Organization(s): Neil
Ketchell, AEA Technology, UK
User’s Guide:
AEA EGRESS User Manual, August 1993
Technical References:
Modeling of crowd evacuation: guidance on the
method,
AEA/CS/16405219/5/A, August 1995
"The EGRESS code for human
movement and behaviour in
emergency evacuations", Ketchell, N., Cole,
S., Webber, D.
M., Marriott, C. A., Stephens, P. J., Brearley,
I. R. Fraser, J.,
Doheny, J., Smart, J., Engineering for crowd safety,
Institution of Civil Engineers, London, 17-18
March 1993.
Validation References: "When
and how will people muster? A simulation approach
(Description and validation of the EGRESS code)".
Ketchell
N, Hiorns N, Webber D M, Marriott C A, Presented
at
"Response to incidents offshore", Aberdeen,
June 1993.
OR
"Assessment and simulation of crowd evacuation
issues",
Ketchell N, Webber D M, Cole S K, Stephens P J,
Hiorns N,
In "Fire Engineering and Emergency Planning
- Research
and Applications", Ed R Barham, E & FN
Spon, 1996.
Presented at Eurofire '95, Nimes, France, 25-27
March 1995.
Availability:
EGRESS analysis is available on a consultancy
basis. The
software is not currently offered for sale.
Price:
Prices depend on the assessments required.
In EGRESS "people" are modeled as
individuals on a grid. The simulation technique
used is based on the use of cellular automata.
At each "time-step" the "people"
move
from cell to cell based on the throw of a weighed
die. The weights required for the die are
calibrated against information on speed, or flow,
as a function of density, so that the
experimental data can be adequately represented
where it is valid. EGRESS has been
validated against a range of available evacuation
trials by simply drawing up the
configurations and using all the default parameters.
The agreement between the code and
measured evacuation times was of order ±20%,
except where specific features (eg. an
aircraft over-wing exit) were not included in
the default modeling. EGRESS 5.4 has a wide
range of facilities available to account for important
features and these would normally be
used in a simulation.
EGRESS enables an event to be mapped onto the
plan to look at the impact it has on the
available routes as the event progresses. It allows
the impacts of different behaviors to be
evaluated, as well effects of congestion and bottlenecks.
EGRESS can model many thousands of people and
several square kilometers of plan
area, which is typically divided up into separate
floor areas connected by stairways, etc.
EGRESS has been used for a large variety of evacuation
simulations ranging from
offshore oil and gas installations, to ships,
railway stations, chemical plant, aircraft, trains
and places of public entertainment.
