Smoke Alarm User Manual

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Note: This document is based on the recommendations of BS5839 Part 1: 2002. It is intended only as a guide to the application of fire detection systems.
Reference must be made to relevant national and local standards.
Application Guide
2.6 MAINTENANCE OF FIRE DETECTORS
Caution: Prior to carrying out any maintenance or testing
on a fire alarm system, the relevant authorities and staff
should be notified.
Over time, the sensitivity of a smoke detector can change
owing to a build-up of dirt in the detector chamber. In most
modern detectors this effect is slowed by the inclusion of drift
compensation functions, however the build up can still lead to
a risk of false alarms or change in the detector sensitivity.
The frequency of maintenance requirements on a detector will
depend on site conditions, obviously the dirtier the site the
more frequent maintenance will be required. The optimum
frequency for a given site should be determined over a period
of time after the commissioning of the fire system.
All System Sensor detectors (smoke, heat, or multi-criteria)
are designed such that they can be easily dismantled for
maintenance. Instructions are given for maintenance in the
instruction manual supplied with each detector. Normally it
is sufficient to use compressed air or a vacuum cleaner to
remove dust from the detector chamber.
Once maintenance on a fire detection system has been
completed, it should be re-tested.
2.7 ROUTINE FUNCTIONAL TESTING OF FIRE DETECTORS
BS5839 Part 1: 2002 gives a range of recommendations
regarding routine testing of a fire detection system.
A weekly test should be carried out on a fire detection system
by activating a manual call point to ensure that all fire alarm
signals operate correctly, and that the appropriate alarm
signals are clearly received. This test should be carried out at
approximately the same time each week, using a different call
point in rotation.
In order to comply with BS5839 Part 1: 2002, periodic
inspections, servicing and functional tests of the fire alarm
system should be carried out at intervals determined by
an assessment of the site and type of system installed, not
normally greater than six months.
It is recommended to perform regular functional tests on all
fire detectors annually. These annual tests may be carried
out over the course of two or more service visits during the
twelve-month period.
System Sensor detectors include various means of testing the
system without using smoke, dependent on the detector range
being tested, including magnet switches and laser test tools.
Codes and standards (in the UK BS5839 Part 1:2002, Section
6) now require functional tests to introduce smoke through
the smoke detector vents and into the sensing chamber. It also
calls for heat detectors to be tested by means of a suitable
heat source, and not by a live flame. CO fire detectors now
also need to be functionally tested by a method that confirms
that carbon monoxide can enter the chamber.
Many installers use a set of equipment that consists of a
complete range of test tools that locate on the end of the pole
such as those available from No Climb Products Ltd. (www.
noclimb.com) in order to aid compliance with codes. Tools
exist for testing smoke, heat, and CO fire detectors, whilst
also enabling them to be accessed and removed at heights up
to 9 meters from the ground.
Using functional test equipment, along with those
maintenance tools available from System Sensor, should
ensure that the system remains at its optimum operation for
many years.