Ceiling Jet Flows.
Ceiling Jet Flows.
(802 K)
Evans, D. D.
NFPA SFPE 95; LC Card Number 95-68247;
SFPE Handbook of Fire Protection Engineering. 2nd
Edition. Section 2. Chapter 4, National Fire
Protection Assoc., Quincy, MA, DiNenno, P. J.; Beyler,
C. L.; Custer, R. L. P.; Walton, W. D., Editor(s),
2/32-39 p., 1995.
Keywords:
fire protection; fire protection engineering; ceiling
jets; fire growth; high temperature gases
Abstract:
Much of the hardware associated with detection and
suppression of fires in commercial, manufacturing,
storage, and recently constructed residential buildings
is located near the ceiling surfaces. In the event of a
fire, hot gases in the fire plume rise directly above
the burning fuel and impinge on the ceiling. The
ceiling surface causes the flow to turn and move
horizontally under the ceiling to other areas of the
building remote from the fire position. The response of
smoke detectors, heat detectors, and sprinklers
installed below the ceiling so as to be submerged in
this hot flow of combustion products from a fire
provides the basis for the building fire protection.
Studies quantifying the flow of hot gases under a
ceiling resulting from the impingement of a fire plume
have been conducted since the 1950s. Early studies at
the Fire Research Station in Great Britain, and more
recently at Factory Mutual Research Corporation, the
National Institute of Standards and Technology (NIST),
and at other research laboratories, have sought to
quantify the gas temperatures and velocities in the
hottest portion of the flow produced by steady fires
beneath smooth, unconfined horizontal ceilings.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899