Particulate Entry Lag in Smoke Detectors (NISTIR 6242)

Published

October 1, 1998

Author(s)

Thomas G. Cleary, Artur A. Chernovsky, William L. Grosshandler, Michael D. Anderson

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).

Citation

NIST Interagency/Internal Report (NISTIR) - 6242

Report Number

6242

NIST Pub Series

NIST Interagency/Internal Report (NISTIR)

Pub Type

NIST Pubs

Download Paper

https://doi.org/10.6028/NIST.IR.6242

Keywords

fire research, fire science, fire suppression, smoke detectors, time lag, sensors, signals

Citation

Cleary, T. , Chernovsky, A. , Grosshandler, W. and Anderson, M. (1998), Particulate Entry Lag in Smoke Detectors (NISTIR 6242), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.IR.6242 (Accessed October 8, 2025)