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Author
Cooper, L. Y.
Title
Smoke Movement in Rooms of Fire Involvement and Adjacent Spaces.
Coporate
National Bureau of Standards, Gaithersburg, MD
Journal
Fire Safety Journal, Vol. 7, No. 1, 33-46, 1984
Report
NBSIR 83-2748, July 1983, 38 p.
Distribution
Available from National Technical Information Service
Keywords
combustion products | compartment fires | egress | enclosures | fire detection | fire growth | hazard analysis | mathematical models | room fires | smoke movement | tenability limits | smoke filling | multiroom fires
Abstract
Key to the solution of fire safety design problems is the capability to predict the dynamics of enclosure fire environments. This paper presents a detailed qualitative description of the generic phenomena which occur during typical fire scenarios. The focus of attention is on the effects within building compartments of fire involvement, i.e., compartments made up of a single enclosed space or a space of two or more rooms interconnected by significant penetrations such as open doors or windows. Throughout the dicussion reference is made to quantitative methods for predicting some of the most significant of these effects. Reference is also made to available mathematical/computer models which use these latter methods to quantitatively predict the overall fire environment. The basic topics that are covered are: fire growth in combustibles of fire origin; development of the fire plume and interaction of the plume with the ceiling surface; generation of ceiling jet flows which lead to actuation of detection/intervention hardware; interaction of ceiling jets and wall surfaces; growth of the smoke layer; development of wall flows which can be instrumental in drawing smoke down from the upper smoke layer into the relatively uncontaminated, shirking lower ambient environment; downward radiation from the high temperature smoke layer and upper enclosure surfaces which can ultimately lead to flashover; onset of conditions which are untenable for human occupancy or property survivability. Topics related to fire generated environments in multiroom fire/smoke compartments include: dynamics of the smoke and fresh air exchange between the room of fire involvement and the adjacent spaces; dynamics of door/window plumes, ceiling jets, smoke filling and well flows within adjacent spaces; actuation of adjacent space fire detection/intervention hardware; and onset of adjacent space untenability.