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.

Application Guide

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.

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System Sensor manual Maintenance of Fire Detectors, Codes and standards in the UK BS5839 Part 12002, Section
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BS5839 specifications

System Sensor BS5839 is a standard that pertains to fire detection and alarm systems, providing guidelines for the design, installation, and maintenance of these essential safety tools. It is crucial for safeguarding lives and property, ensuring that fire detection systems are effective and reliable. The BS5839 standard, established in the UK, covers a wide range of fire alarm system types, including conventional, addressable, and wireless systems.

One of the main features of BS5839 is its comprehensive classification of fire detection systems. The standard divides systems into categories based on the level of risk and the environment in which the system will operate. This classification helps ensure that the system installed meets the specific needs of the building and its occupants. For example, Category L systems are meant for life safety, while Category P systems are designed to protect property.

The technologies underpinning BS5839 include various types of detectors, alarm devices, and control panels. Smoke detectors, heat detectors, and multi-sensor detectors are prominent among the devices specified in the standard. Smoke detectors use photoelectric or ionization principles to detect smoke and signal an alarm, while heat detectors respond to temperature changes. Multi-sensor detectors combine both smoke and heat detection technologies to provide a more reliable response to fire conditions.

Another key characteristic of BS5839 is the emphasis on regular testing and maintenance. The standard outlines procedures to ensure that systems remain operational and effective over time. This includes routine system checks, functional testing, and more in-depth inspections at regular intervals. Ensuring that systems are maintained according to BS5839 is vital for compliance with insurance requirements and for safeguarding against potential legal liabilities.

Furthermore, BS5839 highlights the importance of staff training and awareness. It emphasizes that personnel responsible for fire safety must be adequately trained in the operation and response to fire alarm systems. This ensures that in the event of a fire, occupants are prompted to take appropriate action and evacuate safely.

In summary, System Sensor BS5839 provides a crucial framework for fire detection and alarm systems. Its classification of systems, incorporation of advanced technologies, and emphasis on maintenance all contribute to enhanced safety and compliance, protecting lives and property effectively.
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