Determination of the evacuation time pertinent to the projected area factor in the event of total evacuation of high-rise office buildings via Staircases

Abstract

This paper provides predictions of the time required for the total evacuation of high-rise office buildings via staircases. It refers to evacuation drills carried out in three high-rise administration buildings in October, 1976, by the Research Institute for Fire Protection at Karlsruhe (Forschungsstelle für Branschutz-technik an der Universität Karlsruhe). Total evacuation times pertinent to the projected area factor, which correspond to a certain flow density on the means of escape, are determined based on a mathematical method developed by Predtetschenski and Milinski. Equations and graphs are derived for the evacuation time in terms of the projected area factor and the number of persons per floor, as well as for the corresponding change of crowd movement on stairs. The values for the predicted evacuation times are compared with the values measured during the evacuation tests, and the limits of the projected area factor are estimated for buildings of similar geometric configurations.