Abstract: Emergent evacuation in buildings becomes necessary in case of an accident such as fire, earthquake, toxic gas release etc. Bomb threat also makes it prudent for the occupants to escape out in a minimum possible time. Emergent evacuation is possible when minimum but adequate numbers of escape routes are available to the occupants for efficient movement and rapid evacuation. Inadequate size of routes creates bottlenecks and backtracking that may cause stampede, crushing and trampling. Therefore, it is imperative to examine the building design with respect to numbers & size of exits, stairwells and other substantial features of the building egress plan. Planning of the movement of people is of great importance to the safety measures. Therefore, the systematic scheduling for exit of occupant inside the building is the fundamental requirement for efficient evacuation to minimize the loss of life and avoiding the congestion, backtracking and circling. In this direction, many mathematical models have been developed to compute the evacuation time. In CBRI, attempts have been made to compute the possible time of evacuation with adequate number of escape routes of adequate size to avoid stampede, crushing and trampling. In this paper the attention has been drawn on the rapid evacuation of a building without bottlenecks in the escape routes. The model discussed here based on graph theoretical approach considering the parameters like Dynamic Capacity (DC) and Traversal Time Step (TTS) of each evacuation path. The waiting time for each path has also been minimized using queuing theory. For optimal utilization of paths, the service rate, throughput and response time of each path has also been considered.
Keywords: Evacuation, Escape Route, Egress, Network, Optimization, Mathematical Modeling
[1] I. Furin, Pedestrian planning and design, Metropolitan association of urban designers and environmental planners, New York, 1971
[2] L.G. Chalmet, R.L Francis and P.B. Saunders, Network Models For Building Evacuation, Management Science, Vol. 28, No. 1, pp. 86-105, January, 1982.
[3] R,L Francis, and L.G. Chalmet, A Negative Exponential Solution To An Evacuation Problem, Research Report No. 84-86, National Bureau of Standards, Center for Fire Research, Washington DC, 20234, October, 1984.
[4] T.M. Kisko, and R.L. Francis, EVACNET+: A Computer Program to Determine Optimal Building Evacuation Plans, Fire Safety Journal, 9:211-222, 1985.
[5] M.Y. Roytman,, Principles of Fire Safety Standards for Building Construction, published for the National Bureau of Standards, Washington, DC By Amerind Publishing Co., Pvt. Ltd. New Delhi, India, 1975.
[6] V.M. Predtechenskii and A.I. Milinskii, Planning for foot traffic flow in buildings, New Delhi, Amerind publishing co. pvt. Ltd., 1978