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Author
Cleary, T. G. | Chernovsky, A. | Grosshandler, W. L. | Anderson, M.
Title
Particulate Entry Lag in Smoke Detectors.
Coporate
National Institute of Standards and Technology, Gaithersburg, MD
Report
NISTIR 6242
October 1998
Distribution
Available from National Technical Information Service
Book or Conf
National Institute of Standards and Technology. Annual Conference on Fire Research: Book of Abstracts. November 2-5, 1998, Gaithersburg, MD, Beall, K. A., Editors, 11-12 p., 1998
Keywords
fire research | fire science | fire suppression | smoke detectors | time lag | sensors | signals
Abstract
It is well known that smoke detectors do not instantaneously respond to smoke concentration directly outside the detector. The smoke must be transported through the detector housing to a sensing location inside the detector. The sensing time lag is a function of the free stream velocity of the smoke laden air as it approaches the detector. Previous work correlated the detector time lag as a first-order response with a characteristic time defined as L/V, where L is a characteristic length and V is the characteristic velocity (ceiling jet velocity of free stream velocity).