Citation

Fissan H, Otto E, Dixkens J. Fire Safety J. 1997; 29(2-3): 205-215.

Copyright

(Copyright © 1997, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

For certain application areas in fire detection, air sampling systems are used which sample at different locations. The sampled air is transported to one fire detector. The aerosol coming from a starting fire, transported to at least one of the openings of the pipe system, is modified mainly because of non-representative sampling at the intake, particle losses in the pipe and dilution by sampled air from other openings.These changes of the aerosol during transport for a model system designed using design rules given by the manufacturer, are calculated. The main goal of this article is to give information regarding which particle size range a sampling is possible for, to impart [alpha] feeling about problems which may occur. For very small particles (5 [mu]m, the particle losses become important. However, dilution is the most important factor. The reduction in concentration by using a multiple sampling system can be counteracted if the alarm level of the detector is reduced correspondingly. In order to guarantee the same detection level, the alarm level for the investigated model system has to be reduced to less than 1[middle dot]8% of the alarm level without a sampling pipe system.