Diversion Relays and Supervisory Buzzers

No British Standard exists specifically for this item and indicating panels. A diversion relay permits the audible signal until the system is reset.

Self Contained Fire Alarm Units

These units normally incorporate break glass contact, fire alarm sounder, battery and charger. The units are suitable for small hotels, shops, guest houses etc. A single sounder can be expected to give a 3 hour alarm. This reduces to one hour when three additional 6 bells are installed. Self contained units incorporating smoke detectors are also available, They normally include visual and audible indicators of the circuit and power supply faults in accordance with the British Standard.

Points to consider

• Open, closed or fault monitored circuit

• Smoke detectors to be incorporated

• Operating voltage

• Number of additional bells

• Resistance of connecting cables

• Spare glasses for contact

• Mains supply connection for unit

• Spare cartridge fuses

Wiring and Installation

Recommendations as to suitable types of wiring and cables are included in the British Standard together with minimum conductor sizes, It also indicates suitable cable types for monitored or non monitored circuits according to the type of installation. The Institution of Electrical Engineers Regulations for the Electrical Equipment of Buildings Regulations refers to the necessary segregation of fire alarm circuit wiring. Provision should be made for end line devices to be fitted, where necessary, for line fault monitoring.

Points to consider

• Conductor rating for alarm load and volt drop requirements

• Compliance with the British Standard and IEE Regulations for Segregation of Services

• Cable type and installations suitable for monitored or non monitored systems

• Earthing in accordance with the IEE Regulations

• Cables suitable for ambient air temperature

• Mains voltage power supply to control equipment in accordance with the Regulations

• For surface laid insulated and sheathed cables protection provided where mechanical damage or attack by rodents or where cables are installed less than 2.5 metres from floor

Connection to Fire and Rescue

British Standards discuss the various methods available.
Some of the applied methods:

1. One method of connection used to be a direct monitored line which used to be called a PW (dedicated private wire/line) eg to the fire service, which is not used very often these days.

2. Another method is a connection to an ARC (Alarm Receiving Centre) and is mostly used

Inspection and Servicing

This information is provided for the general guidance of fire detection and fire alarm system users. As it is a summary, it omits much of the information included in BS5839 part 1. It is therefore not intended to be a replacement for the detailed recommendations included within British Standard.

Routine testing by the user

It is vital for a regular test to be undertaken to ensure that there has not been a major failure of the entire fire detection and fire alarm system that may otherwise go unnoticed.

Weekly tests

• Test a manual call point during working hours to cheek that the control panel and alarm sounders operate satisfactorily
• Each week, a different manual call point should be tested
• Voice alarm systems should be tested weekly in accordance with BS5839 Part 8. If the system is connected to an Alarm Receiving Centre (ARC) for calling the fire brigade, it is very important that the ARC is notified before testing commences and when it is complete

Monthly tests

• Any automatically started generator used for the fire detection and fire alarm system should be tested
• Any vented batteries used as a standby power supply for the fire detection and fire alarm system inspected

Inspection and Servicing by a competent person

The inspection and servicing should be undertaken by organisations with the appropriate competence. This can be assured by the use of organisations that are third party certificated, by a UKAS accredited certification body, specifically to carry out inspection and servicing of fire detection and fire alarm systems.

Periodic inspection and testing

• The period between visits to undertake inspection and service should he based upon a risk assessment but the maximum period between visits should not exceed six months.
• The log book should be inspected
• A visual inspection should be made to check whether structural or occupancy changes have been made that require changes to the fire detection and fire alarm system.
• False alarm records should be checked and relevant action taken if necessary
• Batteries should be checked and tested
• Control panel functions should be checked and tested
• Fire alarm devices should be tested
• Facilities for automatic transmission of alarm signals to an alarm receiving centre (ARC) should be checked after advising the ARC of the proposed actions
• All fault indicators and circuits should be tested and checked
• Printers should be tested
• Other checks and tests recommended by the manufacturer should be carried out
• Outstanding defects should be reported and the logbook completed and servicing certificate issued.
• The recommended period between successive inspection and servicing visits should not exceed six months.

Quarterly inspection of vented batteries

• Vented batteries should be examined by a person with relevant competence and should be topped up if necessary

Inspection and test of a system over a 12 month period

• The switch mechanism of every manual call point should be tested
• Every automatic fire detector should be examined and functionally tested. This includes, but is not limited to; smoke detectors, resettable heat detectors, optical beam smoke detectors, aspirating fire detection systems, carbon monoxide fire detectors and flame detectors
• All fire alarm devices (both visual and audible) should be tested
• Certain filament lamps should be replaced
• Radio fire detection and fire alarm system signal strengths should be checked
• Visual inspection of readily accessible cable fixings should be undertaken
• The cause and effect programme should be checked
• The standby power supply capacity should be checked
• Other annual checks and tests recommended by the system component manufacturers should be undertaken
• Outstanding defects should be reported and the servicing certificate issued.
• As this is labour-intensive servicing, it is recommended that the work can be spread over two or more service visits during each twelve-month period

Non-routine attention

The arrangements in the above section, inspection and servicing are intended to maintain the system in operation under normal circumstances. However, from time to time, the fire alarm system is likely to require non-routine attention, including special maintenance. Non-routine maintenance includes:

• special inspection of an existing fire alarm system when a new servicing organization takes over servicing the system;
• repair of faults or damage;
• modification to take account of extensions, alterations, changes in occupancy or false alarms;
• action to address an unacceptable rate of false alarms;
• inspection and test of the system following a fire.

For instance recommendations on unacceptable rate of false alarms:

Any false alarm investigation and subsequent modifications to the system takes into account the guidance provided in BS5839. Any organisation undertaking false alarm investigations and related remedial work should be able to demonstrate their competence to undertake such work. This section contains comprehensive information on all aspects of limitation of false alarms.

The measures to limit false alarms are divided into eight groups:

• Siting and selection of manual call points
• Selection and siting of automatic fire detectors
• Selection of system type
• Protection against electromagnetic interference
• Performance monitoring of newly commissioned systems
• Filtering measures
• System management
• Regular servicing and maintenance

A policy has been devised by the Department of Communities and Local Government for Fire and Rescue Services which is Policies for Dealing with Unwanted Fire Signals from Automatic Fire Alarms.

Statutory Regulations

In addition to government legislation, byelaws and local policy documents exist, created by local authorities at both district and county level, demanding the installation of fire alarm systems. These vary from area to area and advice must be sought from the appropriate local authority on any regulations in force.

British Standards Relating to Fire Alarms

British Standards: Commercial Fire Detection Systems Recommendations

September 1st, 2014

The British Standards feature a set of recommendations on the fire alarm and detection systems for businesses and other commercial properties.

Here’s a summary of the recommendations specified by the British Standards

British Standards Recommendations for Commercial Fire Alarm Systems

1. a) The category of fire detection and alarm system required should be stated in recommendations from the relevant enforcing authorities or insurers. This is so that there is no ambiguity over the most appropriate category of fire alarm system for a property.
2. b) The person responsible for purchasing of an alarm system for a commercial property should inform the system’s designer of the category of detection system required. This should for example be stated in tender specifications.
3. c) When no category is set in the requirements, it is the responsibility of the system designer to make it clear to the purchaser as to which category of system is proposed.
4. d) In situations a, b and c – further information as to the location of where fire detectors should be placed in a building should be provided. The only exceptions are for L1 or P1 systems
5. e) Category L1, L2, L3 and L4 fire detection systems (which are for the protection of life) should also satisfy the recommendations of a Category M system. A Category M system is one that is defined as needing manual operation/human input to activate the alarm.
6. f) In some cases, Category M manual fire detection systems may be required in conjunction with a Category P1, P2 or L5 system. Under these circumstances these will be named as follows:

- Category P1/M
- Category P2/M
- Category L5/M

1. g) When more than one category of system is required to satisfy your building’s fire alarm system requirements, this should be referred to in the following way:

- Category L2/P2
- Category L3/P2

1. h) The system design certificate is a document that should state the category of fire detection and alarm system designed. It should also include details on the areas of a building that are protected by automatic fire detectors. This is excepted in the cases where Category M, L1 or P1 systems are installed.

British Standards: Categories of Fire Detection Systems

What are the British Standards for?

The British Standards are an essential resource for those who design and install fire detection systems in commercial properties, as well as for local authorities, housing associations and the fire brigade. They outline the types of fire detection and alarm systems that should be installed in commercial buildings to give protection against fire.

These standards act as a guide to ensure fire alarm systems fulfil two key objectives – saving lives and protecting property. Due to the huge variety of applications for fire detection systems, the British Standards divides them into several different categories. Here’s a run through of the categories, the levels of system and what they mean.

Category M Fire Detection Systems

Alarms under this category are manual fire alarm systems where the alarm must be activated, for example by a person using a fire call point. These systems tend to be fairly basic and require a human to discover the fire and take action.

Category L Fire Detection Systems

Category L systems are automatic fire detection and alarm systems with the aim of protecting life. There are 5 levels within this category, each offering a different level of fire protection.

L1 – Earliest possible fire detection

Fire alarms should be installed throughout a building to provide the earliest possible warning. This is critical in commercial premises where there are many people present on site.

L2 – Fire detectors for defined areas

This level of protection requires alarms to be installed in defined parts of a building to give occupants as much time as possible to be evacuated, before escape routes become impassable due to smoke and flames.

L3 – Protecting paths to fire escape

Similarly to level 2, this level involves installing detectors in defined areas, the difference being with level 3 that fire detectors should be placed in rooms that open onto an escape route.

L4 – Protection of fire escape routes

Fire detectors should be placed along escape routes and in other circulation areas, such as corridors and stairways. The objective of this is to protect escape routes so that people can exit a building safely during the event of a fire.

L5 – Localised fire protection

In some buildings fire detection systems may be needed to satisfy a specific fire safety requirement. For example there may be an area where a fire would pose a high risk to the lives of occupants. Under these circumstances, detectors would be required in these locations whether this includes just one room or even entire section of a building.

Level 5 may be needed as an additional requirement to those mentioned under levels 1, 2, 3 and 4.

Category P Fire Detection Systems

Category P systems have the primary aim of protecting property from fire. There are 2 levels, which offer a different level of protection depending on the fire threat.

P1 – Complete fire protection for earliest possible warning

These detection systems offer the earliest possible fire warning. Detectors and alarms should be placed in all areas of a building, so that the moment a fire breaks out the fire brigade can be alerted to stop the spread of the fire and minimize damage to property.

P2 – Fire detectors for defined parts of a building

Where the threat to property and therefore business is high in particular areas of a building, more specific coverage may be needed. Areas with high fire risk, particularly where there are several fire hazards present will require special warning. This could refer to a single room but it can also be extended to cover the entire floor of a building.

 

Fire Alarm British Standards

BS 5839-1:2013	Fire detection and fire alarm systems for buildings. Code of practice for system design, installation, commissioning and maintenance
BS EN 54-11:2001	Fire detection and fire alarm systems. Specification for manual call points has replaced BS 5839-2:1983
BS 5839-3:1988	Specification for automatic release mechanisms for certain fire protection equipment.
BS EN 54-4:1998	Fire detection and fire alarm systems. Power supply equipment has replaced BS 5839-4:1988
BS EN 54-2:1997+A1:2006	Fire detection and fire alarm systems. Control and indicating equipment has replaced BS 5839-4:1988
BS 5839-6:2013	Fire detection and fire alarm systems for buildings. Code of practice for the design, installation and maintenance of fire detection and fire alarm systems in dwellings
BS 5839-8:2008	Fire detection and fire alarm systems for buildings. Code of practice for the design, installation, commissioning and maintenance of voice alarm systems
BS 5839-9:2003	Fire detection and alarm systems for buildings. Code of practice for the design, installation, commissioning and maintenance of emergency voice communication systems

Guides to BS 5839

BIP 2109:2008	The Design, Installation, Commissioning and Maintenance of Fire Detection and Fire Alarm Systems: A Guide to BS 5839-1 (3rd edition)
BIP 2044:2004	A Guide to BS 5839-6:2004
BIP 2124:2009	The Design and Installation of Voice Alarm Systems. A Guide to BS 5839-8

Associated British Standards

BS 5446-2:2003	Fire detection and fire alarm devices for dwellings. Specification for heat alarms
BS 5446-3:2005	Fire detection and fire alarm devices for dwellings. Specification for smoke alarm kits for deaf and hard of hearing people
BS 5979:2007	Remote centre’s receiving signals from fire and security systems. Code of practice