A Review of Building Evacuation Models - NIST Virtual Library

factors relate to delays, deviations and lack of comfort that individuals seek to avoid when
deciding about their next step.
The decisions about each step are made according to an individual’s preferences, location,
objectives, and recent experience. These are also sensitive to local conditions (crowding or lack
thereof), context (stairs, escalators), and projected intentions of neighbors.
Legion 66 claims to have overturned key assumptions on behavior and movement in crowds.
They state that “people's circulation through a space is determined not only by their density but
also by the specific features of the local geometry” 66 . Movement is affected not only by input
variables chosen for each individual person, but also by factors such as knowledge of the
environment and the person’s state of readiness. These correspond to occupants’ interaction
with signage and information points throughout the building.
Output: Bitmap and video files and the ability to choose the data output that is of interest;
graphs or detailed metrics for individual and crowd experiences. Examples of the output are the
following:
• Usage maps
o Space utilization - the extent to which different areas have been visited
o Density and speed maps
o Evacuation maps – how quickly areas empty
o Inconvenience, Frustration, and Discomfort
• Graphs
o Densities, counts, flows, time spent inside, journey time, queuing time, waiting
time, speed, etc. can all be plotted as graphs, exported as pictures and/or
spreadsheets and/or raw data
• Animations
Use of fire data: This capability is under development. Currently, the model allows for output
from fire modeling software to be indirectly incorporated into the model, which converts certain
areas of the building into “undesirable zones” and/or zones through which movement is difficult.
Import CAD drawings: CAD drawings are imported into the model. The following formats
are supported by the model: .DXF, .DWG, and .DGN. Also, the user can easily change spatial
configurations in the building by using the Legion software. The user also inputs the following
onto the CAD drawing in Legion; entrances, exits and route options, facilities (gates, waiting
areas), scheduled events (train announcements, service times), and the arrival profile of the
people and their desired destinations.
Visualization capabilities: 2-D capabilities are part of the standard suite. Also, 3-D
visualization is available through a separate module.
Validation studies: The following validation studies have been performed on the Legion
model:
• Papers in preparation on quantitative validation based on proprietary measurements
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