Influence of Wooden-Based Dusts on Smoke Fire Detectors

Apply

Influence of Wooden-Based Dusts on Smoke Fire Detectors

Journal Title: Safety & Fire Technology - Year 2016, Vol 42, Issue 42

Abstract

Aim: There is a need of fire detection solutions which are sensitive to deceptive signals. They can lead to false fire alarms. One of such signals is the activation of detectors in case of wooden dusts accumulated in the protected area which is regarded by the detector as smoke with large particles. This paper describes selected experimental results on various detectors and different wooden dusts. The aim of this project is to select a detector that is highly resistant to dust particles. Introduction: During designing fire detection systems there is always a problem in a proper selection of fire detectors operating in environments where there are various sources of false alarms. Initially, the influence of cellulose dusts as could be observed during the production of newspapers at the printing house was studied. Then the influence of other dusts was analyzed. During the measurement of smoke particles of different sizes the influence of particles on the detection cannot be explicitly determined. Due to this fact, tested dust was divided taking into consideration the size of the particles where the diameter was 100 μm, 200 μm and 500 μm. It made it possible to test the influence on the operation of the detectors of not only wooden-based materials but also of the size of dust particles. Methodology: During the tests the methodology of measuring the influence of dust on the activation time of detectors was prepared. The pressure of the compressed air was set at 1,5 bars together with the opening time of the valve of the compressed air container in order for the dust to be emitted evenly in the test chamber. If the valve opening time was too short, the dust remained in the container. If it was too long – the dust was blown all over the chamber. The optimum time was set as 3 s. Tested detectors were located by the ceiling of the chamber in the following manner: transmitter-receiver, transmitter-prismatic mirror on opposite walls. Measurement results were registered using a computer system. Conclusions: As a result of the conducted tests, which included the behaviour of fire detectors smoke, the best design solution was determined that best coped with duste present in protected areas. It is OSID smoke detection system. It is a result of how the signal was processed by the detector. The size of dust particles and, to a smaller degree, type of dust with respect to the tested species of wood influenced the operation of the smoke detector.

Authors and Affiliations

st. bryg. dr inż. Waldemar Wnęk, inż. Marcin Jargieło, mł. bryg. dr inż. Rafał Porowski

Keywords

systemy sygnalizacji pożarowej czujki dymu fałszywe alarmy pył drzewny fire detection systems smoke detectors false alarms wooden dust

Fire Hazard of Bridge Structures in Light of Current Regulations

Aim: The main purpose of this article is to provide a discourse about current regulations dealing with fire safety of bridges in Poland and share the outcome with a wider group of specialists, who are involved with fire...

Application of Computational Fluid Dynamics CFD for Modeling of Protection of Premises by Fixed Gaseous Extinguishing System

Aim: The problem of fire safety of areas protected by fixed gaseous extinguishing system is discussed. Increasing the accuracy and reliability of the modeling of gas extinguishing process can be achieved by using methods...

EP ID EP112519
DOI 10.12845/bitp.42.2.2016.4
Views 125
Downloads 0