A Review of Building Evacuation Models - NIST Virtual Library

A.28 VEgAS
Developer: G.K. Still, Crowd Dynamics Ltd., UK
Purpose of the model: The purpose of this model is to simulate human behavioral response
under stress conditions and through the fire environment, monitoring toxicity levels and physical
containment 73, 74, 112 . All occupants and components of the building operate in “real-time” in a
“virtual reality (VR) world.”
Availability to the public for use: Unknown. Myriad (described in Section A.28), a
macroscopic evacuation model, has seemed to replace the use of the model by Crowd Dynamics,
Ltd.
Modeling method: This is a behavioral model
Structure of model: This is a fine network system.
Perspective of model and occupant: The model views the occupants as individuals. Each
occupant or “human character” is programmed to respond to the following:
• Proximity to fire/smoke/temperature
• Time from the initial alarm
• Proximity to the exit
• Behavior of their neighbors
Each occupant has intelligence and a number of choices during the evacuation.
According to Gwynne and Galea 113 , the user specifies a defined route to the exit, instead of
modeling wayfinding capability. The route is dynamically affected by the fire environment, as
shown in the VEGAS diagram.
Occupant behavior and movement: The occupant behavior is artificial intelligence, which
involves simulating the individual thought processes. The behavior/movement processes are
shown in Figure A.28.
The model can use such input as the products of combustion in the building spaces (fixtures,
finishes, and furnishings), the fire growth rate, the effect of opening and closing doors, the effect
of smoke, toxicity to the occupants, and smoke extraction systems to simulate the evacuation.
Each occupant is programmed to respond to the proximity to the fire environment (fire, smoke,
and temperature), the time from initial alarm, proximity to the exit, and the behavior of his/her
neighbors. VEGAS uses a series of programmable events (by the user) to trigger the occupant
respond/ignore cycle.
A-101