Selecting one of the following premise types, you are required to write a report detailing the features you would expect to find in the fire safety strategy for the building:
Michelle_Michy
20191118153351materials_1.zip3b. Fire Safety in New Build- note.docx
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Fire Safety in the Built Environment Module 6FF011
Note 3b Fire Safety in New, Extended or Altered Buildings
Fire Safety in new, extended or altered buildings is the responsibility of the building owner. The responsibility for checking that the Building Regulations have been met falls to Building Control Bodies – either from the Local Authority (Building Control Department) or Approved Inspectors from the private sector. The person carrying out the work has the choice of where to get approval for the building work.
There are three relevant guidance documents:
· General guidance, applying to most building work (ADB and other government guidance to support legislative requirements)
· Advanced guidance (BS 9999) essentially introduces a middle route between ADB and BS 7974
· High-level guidance on fire safety engineered solutions for larger, more complex buildings (BS 7974)
It is important that those dealing with fire safety matters have a working knowledge of this guidance for background information.
Approved Document Part B Fire Safety
The Department of Communities and Local Government, who is responsible for Building Regulations, has provided all the approved documents online and part B is available from Approved Document Part B Fire Safety .
British Standard 9999
BS 9999 : 2008 Code of practice for fire safety in the design, management and use of buildings is a new standard which uses risk profiles instead of prescriptive methods as used in ADB.
· BS 9999:2008 Code of practice for fire safety in the design, management and use of buildings
British Standard 7974: 2001
Application of fire safety engineering principles to the design of buildings - Code of practice.
This British Standard provides a framework for an engineering approach to the achievement of fire safety in buildings by giving recommendations and guidance on the application of scientific and engineering principles to the protection of people, property and the environment from fire. It also provides a framework for developing a rational methodology for the design of buildings.
This standard applies to the design of new buildings and the appraisal of existing buildings. The use of this standard will facilitate the practice of fire safety engineering and in particular it will:
1. provide the designer with a disciplined approach to fire safety signs;
2. allow the safety levels for alternative designs to be compared;
3. provide a basis for selection of appropriate fire protection systems;
4. provide opportunities for innovative design;
5. provide information on the management of fire safety for a building.
This standard does not provide specific guidance on buildings used for the bulk storage or processing of flammable liquids or explosives. The intrinsic risks associated with such buildings will often necessitate special consideration, which is beyond the scope of this document.
Relevant British Standards
British Standards are available online but are very expensive however if you locate the principle technical reference library in your area you should be able to study them free of charge
http://www.firesafe.org.uk/fire-safety-in-new-extended-or-altered-buildings/
http://solutionsfiresafety.co.uk/BS7974-2001.html
Further sources of information
http://www.bre.co.uk/page.jsp?id=1725
http://www.bre.co.uk/page.jsp?id=1855
http://www.communities.gov.uk/buildingregs
http://www.planningportal.gov.uk http://www.bsigroup.com
__MACOSX/._3b. Fire Safety in New Build- note.docx
5a Fire Alarm Systems- notes.pdf
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Fire Safety in the Built Environment Module 6FF011
Note 5a Fire Alarm Systems
The choice of fire alarm system depends on the building structure, the purpose and use of the building and current legislation. In new or altered buildings the enforcement body is the local
building control, and the relevant guidance.
All existing buildings except domestic premises are subject to The Regulatory Reform (Fire Safety) Order 2005 and the Responsible Person, as defined in the order, has to conduct a fire risk assessment. This FRA will decide the appropriate British standard necessary to provide a suitable and sufficient solution for the premises. The enforcement body is the Fire and Rescue Service and the Department of Communities and Local Government (DCLC) have published a number of guidance documents for premises subject to the RR(FS)O. This is particularly important since none of the legislation gives any detailed information on the type of system required but the guidance usually indicates appropriate British standards. The main standard for fire alarm systems is BS5839
pt1:2013.
This guidance contains brief descriptions of the major components which go to make up a fire alarm system. The points to be considered are intended to highlight the variables which can exist and need
to be considered whilst designing and compiling a specification for component parts.
It is not the object of this note to consider the details of different circuit types or to discuss their
relative merits.
Types of Fire Alarm Systems
All Fire Alarm Systems essentially operate on the same principle. If a detector detects smoke or heat or someone operates a break glass unit (manual break point), then alarm sounders operate to warn others in the building that there may be a fire and to evacuate. It may also incorporate remote signalling equipment which would alert a call monitoring centre at a
remote location.
Fire Alarm Systems can be broken down into four categories:
Conventional Analogue Addressable Addressable Wireless systems
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Conventional Fire Alarm System
In a conventional fire alarm system, a number of call points and detectors are wired to the fire alarm control panel in zones. A zone is a circuit and typically one would wire a circuit per floor or fire compartment. The fire alarm control panel has a number of zone lamps. The reason for having zones is to give a rough idea as to where a fire has occurred. This is important for the fire brigade and of course for the building management. The accuracy of knowing where a fire has started is controlled by the number of zones a control panel has and the number of circuits that have been wired within the building. The control panel is wired to a minimum of two sounder circuits which could contain bells, electronic sounders or other audible devices. Each circuit has an end of line device which is
used for monitoring purposes.
Addressable Systems
The detection principle of an addressable system is similar to a conventional system except that the control panel can determine exactly which detector or call point has initiated the alarm. The detection circuit is wired as a loop and up to 99 devices may be connected to each loop. The detectors are essentially conventional detectors, with an address built in. The address in each detector is set by dil switches and the control panel is programmed to display the information required when that particular detector is operated. Additional field devices are available which may be wired to the loop for detection only i.e. it is possible to detect a normally open contact closing such as sprinkler flow switch, or a normally closed contact opening. Sounders are wired in a minimum of two sounder circuits exactly as a conventional system. Loop isolation modules are available for fitting on to the detection loop/loops such that the loop is sectioned in order to ensure
that a short circuit, or one fault will only cause the loss of a minimal part of the system.
Analogue Addressable Fire Alarm Systems
Analogue addressable fire alarm systems are often known as intelligent fire alarm systems. There are several different types of analogue systems available which are determined by the type of protocol which they use. The bulk of standard analogue detectors available are fairly stupid as the detectors can only give output signals representing the value of detected phenomena. It is left up to the Control Unit to decide whether there is a fire, fault, pre-alarm or other. With a true intelligent analogue system each detector effectively incorporates its own computer which evaluates the environment around it, and communicates to the control panel whether there is a fire, fault or the
detector head needs cleaning.
Essentially analogue systems are far more complex and incorporate far more facilities than conventional or addressable systems. Their primary purpose is to help prevent the occurrence of false alarms. With the analogue addressable system, up to 127 input devices i.e.: smoke detectors, call points, heat detectors, contact monitors and other interface devices may be wired to each detection loop. In addition to the 127 input devices, up to 32 output devices such as loop sounders, relay modules and sounder modules may be connected. Analogue systems are available in 2, 4 and 8 loop versions which means large premises can be monitored from one single panel. Isolator units should be connected between sections of detectors as described for addressable systems.
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Wireless Fire Alarm System
Wireless fire alarm systems are an effective alternative to traditional wired fire alarm systems for all applications. They utilise secure, licence-free radio communications to interconnect the sensors and devices (smoke detectors, call-points, etc.) with the controllers. It is a simple concept, which provides many unique benefits and is a full analogue addressable fire detection system without the
need for cable.
System Design
Before starting, the designer will need to ensure that certain information is available. This may be given in the specification or it may have to be obtained by consultation. As well as the purchaser,
there may be a requirement to consult with other interested parties
Points to consider
The type of system required i.e. L1, L2, L3 etc and where appropriate, parts of the premises to be covered.
The action to be taken in the event of fire Whether other occupants of a multi occupancy building will be affected Whether other work is to be done at the same time. If so then consultation with other
contractors may be required. A Method of calling the fire brigade Whether the type of occupants or activity in the building will require a greater provision of
manual call points than normal
A likely attendance time of the fire brigade
Control and Indicating Panels
Control and indicating equipment performs three principal functions, namely:
Automatic monitoring and control of circuits external to the equipment, such as fire detection and fire alarm device circuits and supply of power to these circuits
Indication of fire signals, fault signals and their location Manual control to facilitate actions such as testing, disablement of devices, triggering of fire
signals, silencing of audible fire warnings and resetting the system after a fire signal
Panels are fully specified in British Standards. This requires that circuits are monitored continuously and that both audible and visual indication is provided for fault and fire alarm conditions. Further requirements include that alarm sounders may only be silenced manually, after which the control panel must provide audible and visual signals until the system is reset. Silencing of alarm sounders must not prevent the alarm being raised in other zones. It should be noted that the standards require all fault/alarm indicator lamps to be in duplicate or a single lamp with audible signal of lamp failure. Control and indicating panels may include facilities for operation of ancillary services such as
fixed fire extinguishing, door closing etc.
The equipment should normally be sited in an area of low fire risk and on the ground floor by the entrance used by the Fire and Rescue Service and preferably viewable from outside of the building.
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It should be located in an area common to all building users and where automatic detection is in use, the Control Panel should be in a protected area. An alarm sounder should be sited next to the Control Unit, but not too near the telephone position. A suitable zone chart of the building should
normally be installed adjacent to the Control Panel.
Points to consider
Number of zones required Surface or flush mounting Maximum alarm load per alarm zone Automatic system, compliance with British Standard Manual system compliance with British Standard Maximum current per detector zone Maximum detectors per zone Open, closed or fault monitored system Single or two stage alarms Provision for connection to remote manned centre Provision for conduit and wiring compatible with
building conduit and wiring system
Provision for operation of ancillary services
Detector Heads
These can be divided into four main types Heat detectors, Smoke detectors, Carbon Monoxide
detectors and Multi sensors detectors.
Heat detectors
Heat sensitive point detectors
Point detectors can again be subdivided to a further two
types.
1. Fixed temperature which will operate when it is exposed to a pre-determined temperature. Normally fixed temperature detectors employ a fusible alloy element which must be replaced after the detector has operated. Different temperature rated elements are available to take account of varying ambient air temperatures.
2. The second type operates on the rate of temperature rise. The rate of rise temperature
detector may also include a fusible element for fixed temperature operation.
Both types are suitable for inclusion in open, closed or line monitored systems.
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Linear detectors
These can take the form of a heat sensitive cable which will operate, at a predetermined temperature, as an open circuit device. Melting of the cable insulation provides a short-circuit between conductors. After operation the destroyed length of cable must be replaced. Linear detectors may be used in large areas such as warehouses. Alternative types of linear detector exist including the heat pneumatic operating on the
rate of rise principle.
Points to consider
Open, closed, fault monitored circuits Temperature setting for fixed temperature fusible elements Spare fusible elements Surface or flush mountings Temperature setting for fusible elements in the rate of rise detection., if included Mounting height Spacing to manufacturer’s recommendations Rate of rise detectors located in positions where abnormal increase in temperature is likely,
e.g. space heating equipment, industrial processes
Smoke Detectors
There are three basic types operating by ionization, light scattering and light obscuring.
Ionisation
These generally contain two chambers. One is used as a reference to compensate for changes in ambient temperature, humidity or pressure. The second contains a radioactive source, usually alpha particle, which ionizes the air passing through the chamber where a current flows between two electrodes. When any of the products of combustion enters the chamber the current flow decreases.
This drop is used to initiate an alarm.
Light obscuring
In the obscuring type the smoke interferes with a light beam between a light source and photo cell, the variation in photo cell output being used to initiate an alarm. This type of detection can be used
to protect large areas with the source and photo cell positioned some distance apart.
Light scattering
The light scattering detector operates on the Tyndall effect, a photo cell and light source are separated from each other by a darkened chamber such that the light source does not fall on the photo cell. The passage of smoke into the chamber causes the light from the source to be scattered
and fall on the photo cell, the cell output being used to initiate an alarm.
The light scattering and light obscuring detectors both, detect visible smoke. The ionization detector and light scattering detector are normally each a single unit suitable for BESA conduit box mounting. In some models the smoke detector head is attached to the main body by a bayonet fixing for easy removal for maintenance or replacement. It should be noted that some detectors are suitable for
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two-wire circuits whereas others require three or four wire connections. Smoke detectors require a continuous power supply. Under quiescent conditions they draw a current of some 100 micro amps, and under alarm conditions, some 45 milliamps. This needs to be borne in mind when sizing the power supply. Smoke detectors generally operate on 24 d.c. Refer to British Standard Codes of Practice and manufacturers literature for information regarding the positioning of smoke detectors. Detectors are not suitable for positioning in kitchens, near fireplaces or areas with excessive exhaust
fumes, or within 2m of air supply ducts or diffusers.
Carbon Monoxide detector
CO fire detectors are electronic detectors used to indicate the outbreak of fire by sensing the level of carbon monoxide in the air. Carbon monoxide, usually known by its chemical formula CO, is a poisonous gas produced by combustion. They are not the same as CO detectors used for home safety which are used to protect residents against carbon monoxide produced by incomplete
combustion in appliances such as gas fires or boilers.
CO fire detectors use the same type of sensor but are more sensitive and respond more quickly.CO detectors have an electrochemical cell, which senses carbon monoxide, but not smoke or any other combustion products. The cells do not require much power, so the detectors can be made electrically compatible with ordinary smoke and heat detectors. As fire detectors they are effective but only for certain types of fire. Deep-seated, smouldering fires produce carbon monoxide, which can be detected some distance from the seat of the fire. For this type of fire a CO fire detector will probably operate before a smoke detector. Smoke detectors, however, will almost always give a better response to a fire that has produced a rising plume of smoke. CO fire detectors will give a poor response to flaming fires. Because CO fire detectors work on different principles from smoke detectors, their false alarm behaviour will be different. For example, they will not be affected by steam, dust, or by most cooking fumes. However, because of their high sensitivity, they may false alarm from harmless transient levels of CO produced by gas heaters starting up, or from vehicle exhaust fumes entering through a window. These events would not affect an optical smoke
detector.
As always, the detector must be selected for the application, to achieve the best balance between fire detection capability and false alarms. There are some known disadvantages of CO fire detectors. One is that the electrochemical cells at the heart of the detectors have a limited life typically seven years and that they are not failsafe. The detector might be “dead” without this fact being apparent. For this reason a means of checking the CO cell has been incorporated. Another clear disadvantage is the poor response to many types of fire, especially life threatening flaming fires.
Multi sensor detector
This detector combines inputs from optical and heat sensors and processes them using a sophisticated algorithm. When polled by the control panel it returns an analogue count which is determined by combined responses from both optical and heat sensors. They are designed to be sensitive to a wide range of fires and may be used in place of an ionisation detector in many instances.
Operating principles
Signals from the optical smoke chamber and temperature sensor are independent, and represent the smoke level and air temperature respectively in the vicinity of the detector; the detector’s micro
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controller processes both signals. The temperature signal processing extracts only rate of rise information for combination with the smoke signal. The detector will not respond to slow increases in temperature but a large sudden change can cause an alarm without presence of smoke, if sustained for 20 seconds. The processing algorithms in the multi-sensor incorporate drift compensation.
Points to consider
Open or closed circuit Fault monitored circuit System voltage Surface or flush mounting Detector operated indicator Two or three-wire system Quiescent current demand Smoke detector location
Spare detector heads
Manual Call Points
A Break Glass Call Point is a device which enables personnel to raise the alarm by breaking the frangible element on the fascia. They should be mounted 1.4m from the floor and sited where they can be easily seen. Manual Call Points should be sited on the floor landings of stairways and at exits to open air. It should be noted that Call Points should be fitted on the floor side of an access door to a staircase so the floor of origin is indicated at the Control Panel. Extra points should be sited, where necessary, so that the greatest travel distance from any point in the building to the nearest call point does not exceed 30m. A greater number of Call Points may be needed in high risk areas or if the occupants are likely to be slow in movement. Flameproof call points are available, also handle operated points for use in areas where broken glass may cause a
hazard.
Points to consider
Open circuit, closed circuit, fault monitored circuit Surface, flush mounting Weatherproof, internal location Contact rating suitable for load under alarm conditions Special call points for flameproof or special hazard areas
Hammer for call points with breakable front plates
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Alarm Sounders
Many types of alarm sounders are available and include:
1. Dome bells – operating mechanism contained within the bell. 2. Bells with operating mechanism external to the bell. 3. Electronic solid state sounders with mono or multi tone output normally in the range of 800
– 1000 Hz. 4. Small sirens operating in the range of 1,200 – 1,700 Hz. 5. Sirens ranging widely in size from 0.17kw to 11kW generally operating in the frequency
range of 400 – 800 Hz.
6. Horns operating in the range of 300 – 400 Hz and either motor or pneumatic operations.
The following figure gives a broad indication of the sound levels of the various alarm sounders. Also indicated are typical sound levels for various industrial and commercial situations. An alarm noise level of not less than 5 decibels above ambient should be provided in general areas for adequate audibility but in sleeping areas a minimum level in the order of 65 decibels and 75 decibels at a bed head to wake sleeping occupants. It should be noted that most dome hells are intended for use with flush conduit or wiring systems. For surface wiring or conduit installations surface mounting adaptor boxes are normally required. Generally bells, electronic sounders and small sirens are available for use with 6, 12, 24 and 48V d.c. Sirens are normally operated at mains voltage, single or three-phase depending on the motor rating. Outdoor sirens should be fitted with heaters and thermostats to protect against low temperature conditions. Public address systems may be used for alarms, and
visual signals may be used in special circumstances.
Points to consider
Operating voltage Installation with surface or flush conduit system Internal or weather-proof installations Bell gong size Colour Motor rating of sirens, note some sirens are rated for continuous duty whilst others are
rated for limited time periods. Television interference suppression
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Whisper at 1 metre = 30dB Casual conversation at 1 metre = 65dB
Threshold of pain = 130dB
Power Units
Two power supplies are required i.e. mains and battery and these are normally built into the Fire Alarm Control Panel. Standby batteries must allow the system to operate without mains for 24 hours longer than the building is likely to be unoccupied and then support the sounders for an additional half hour. If the mains supply is supported by an emergency generator then six hours standby plus half an hour alarm load is sufficient. All modern Fire Alarm Systems are 24 volts. On the medium and larger sized Fire Alarm Systems, the standby batteries will often not fit within the Control Panel.
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Where standby batteries are contained within a separate housing, then this housing must be as close as possible to the main Fire Alarm Control Panel. If the power supply or battery housing is located more than 10 metres from the main Fire Alarm Control Panel then serious volt drop problems can arise. Standby batteries are invariably of the sealed lead acid variety. Use of Nickel Cadmium Batteries is not cost effective and automotive batteries must not be fitted.
Points to consider
System voltage Battery charger output Battery capacity Indication of battery and/or mains supply failure Secondary battery exclusive to fire protection system
Where system voltage exceeds extra-low voltage compliance
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.
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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
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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
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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
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.
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British Standards Relating to Fire Alarms
The appropriate British standards for installation of a fire alarm in non domestic premises is BS 5839- 1:2012 and BS 5839-6:2013 for the design, installation and maintenance of fire detection and fire
alarm systems in dwellings. A number of British Standards relating to fire alarm systems follows.
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
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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
References
http://www.firesafe.org.uk/fire-alarms/
http://www.bsigroup.com/en-GB/
__MACOSX/._5a Fire Alarm Systems- notes.pdf
5c. Summary of the BS 5839- notes.pdf
1
Fire Safety in the Built Environment Module 6FF011
Note 5c Summary of BS 5839-1:2013
BS 5839-1:2013 Fire detection and fire alarm systems for buildings – Part 1: Code of practice for
design, installation, commissioning and maintenance of systems in non-domestic premises
The code of practice in the above British Standards Publication has been developed in line with current national building regulations in respect of both new-build and existing non-domestic premises.
This entry level guide to the Standard aims to address some of the main issues concerning fire detection and fire alarm systems, in respect of general and design queries.
Why might I need a fire detection / fire alarm system for my premises?
As noted in the Foreword (pp iv–vi), "national building regulations require fire detection and fire alarm systems to be installed in many buildings at the time of construction. In addition, legislation requires that, where necessary to safeguard relevant persons in case of fire, existing premises are equipped with "appropriate fire detection and fire alarm systems" (p v).
Annex A (pp 134–135) gives a table of various types of non-domestic premises including, inter alia, common places of work (e.g. shops, offices, factories and warehouses), hotels, schools, hospitals, places of assembly (e.g. cinemas, theatres and churches), residential care homes, shopping centres, etc. This is for guidance only, however, and it is important to note that the list is not exhaustive and that any "reference to particular types of premises does not necessarily mean that all such premises are required by law to have such systems installed" (p v).
For any premises, and as a general rule, best practice in fire safety should always begin with a fire risk assessment, which has the additional benefit of determining whether a fire detection / fire alarm system is required and, if so, what type of system should be installed.
What are fire detection and fire alarm systems?
There are many different types of fire detection / fire alarm system, ranging from the most basic, manually operated, stand-alone devices through to highly sophisticated, digitally controlled networks. It all depends on the size and nature of the premises to be protected. In the context of BS 5839-1, which also applies to extensions and alterations to existing systems, "the term fire detection and fire alarm systems includes systems that range from those comprising only one or two manual call points and sounders to complex networked systems that incorporate a large number of automatic fire detectors, manual call points and sounders, connected to numerous inter- communicating control and indicating panels" (p 1).
It should be noted that this part of BS 5839 does not cover systems whose primary function is to extinguish or control fire. Voice alarm systems, systems combining fire alarm functions with non-fire related ones, audible or visual way-guidance systems designed to complement the fire alarm function, and public emergency call systems (999 or 112) also fall outside the remit of this publication.
Pages 3–10 of the Standard contain a useful glossary of relevant terms and definitions, from "addressable system" through to "zone plan", followed by a commentary on the various categories
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of system (pp 11–13). Referring once again to Annex A, these categories of system are linked to specific types of premises, so it may be helpful to consider what they actually involve.
What is meant by "categories of system"?
There are three main categories of fire detection and fire alarm system, although it should be noted that these are not mutually exclusive. A comprehensive system installed with the principal objectives of protecting both life and property could incorporate elements from all three categories: M, L and P. In particular, as noted on p 12, when selecting the appropriate category of system for a particular premises: "Even in buildings with comprehensive fire detection, the provision of manual call points will still normally be of great value; people in the vicinity of a fire will normally be... able to raise the alarm by use of a manual call point", which action could potentially be taken before the fire is detected automatically. The examples of building type for each category are all taken from the table at Annex A.
Category M: manually operated systems with no automatic fire detectors
Examples of the types of buildings that might install category M systems include non-residential places of work, e.g. offices, shops, factories and warehouses, and smaller non-residential places of assembly where members of the public are typically present during opening hours, e.g. cinemas, theatres, restaurants and leisure centres. This is not an exhaustive list and it may be that additional, automated elements have to be added to the fire detection / fire alarm system in order to satisfy specific insurance requirements, such as protecting the business assets and / or protecting against loss of business through fire.
Category L: automatic fire detection and fire alarm systems principally intended for the protection of life. These are divided into five sub-categories:
L1: systems installed throughout a building, to offer the earliest possible warning of fire and thus the longest possible time for all the occupants to escape.
Examples of premises that might adopt L1 systems include those with sleeping accommodation, i.e. hotels, hostels, hospitals and residential care homes, and larger, non-residential places of assembly such as covered shopping malls.
L2 and L3: systems installed only in defined parts of the building. The objective is to ensure that a fire warning is given early enough to enable occupants, "other than possibly those in the room of fire origin", to escape safely before routes become impassable due to smoke, flames and / or toxic gases. L2 systems have the additional objective of giving early warning in specified areas of high fire hazard / risk, e.g. commercial kitchens and boiler rooms.
Examples of premises for which L2 or L3 systems might be appropriate are the same as for L1. Much will depend on the outcome / recommendations of the fire safety risk assessment, although L3 systems might be particularly suited to larger premises with a phased evacuation policy.
L4: systems installed in those parts of the escape routes comprising circulation areas, e.g. corridors and stairwells
L5: systems in which the protected area(s) and / or the location of detectors is designed to fulfil a specific objective in respect of fire safety other than those covered by categories L1–L4.
Examples of situations in which L4 or L5 systems might be appropriate, frequently coupled with category M elements, include those in which fire could rapidly spread from an unoccupied area of the building and thereby hinder escape from occupied areas. It is important to ensure that
3
automatic fire detectors are positioned such that even cool smoke, which is typical of the early stages of a fire but stays lower to the ground than the hot smoke of a mature blaze, can reach and activate them, such that, for example, magnetic fire door holders are released and the fire doors thereby closed. In other words, these automatic detectors must not be sited so high that the cool smoke passes below them and through the (still open) fire doors. Cool smoke is known as the "silent killer" as it can rapidly overcome the occupants of a building before its presence is even noticed, particularly in premises with sleeping accommodation.
Category P: automatic fire detection and fire alarm systems principally intended for the protection of property. These are sub-divided into the following categories:
P1: systems installed throughout all areas of the building, to offer the earliest possible warning of fire and thus the minimal amount of time between ignition and the arrival of the fire service.
P2: systems installed only in defined parts of the building
Examples of premises that might feature a category P system include those whose property insurer requires automatic fire detection for the policy to be valid. Although, by definition, such systems are geared towards the protection of property and are thus appropriate for unoccupied buildings, in some cases, e.g. if there is a security presence overnight, it may be useful to incorporate some manually operated elements into the system, i.e. M/P1 or M/P2.
What are the main design considerations for an appropriate fire detection / fire alarm system?
Section 2 (pp 18–93) of the Standard covers the various aspects of the design process, divided into 22 sub-sections (8–29). It starts from the definition of the system category that is most appropriate for a particular building and its fire safety requirements and concludes with electrical safety. Each sub-section is presented in a clear and easy to follow format, with a general commentary on the particular design aspect being considered, followed by a list of recommendations. These recommendations typically refer to other, relevant British Standards.
An entry level guide such as this cannot cover system design in detail so what follows is an indication of some of the main points to consider.
System type
We have already looked at relating automatic system categories to particular types of premises in the context of protection of life (L) or property (P), or a combination of the two, and noted that manual (M) systems frequently have a role to play in these. However, it is useful to bear in mind the comment on p 18 that "the appropriate extent of automatic fire detection will normally be determined by a fire risk assessment, rather than a rigid application of a specific Category to every building of a specific type or occupancy".
System components
It is important that system components, e.g. manual call points, detectors, CIE (control and indicating equipment) and other fire alarm devices, conform to relevant British Standards and have undergone type testing to these standards. Furthermore, it is advised that all components used have been certified under a recognized product certification scheme, i.e. third-party certification of product conformity to the relevant standard(s) (p 22).
Monitoring, integrity and reliability of circuits external to control equipment
The design should limit the effect of faults in and / or work on the system. A fault (but not fire) signal needs to be given at the CIE in the event of any failure in the critical signal path, which comprises all
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the components and interconnections between every fire alarm initiation point (whether manual or automatic) and the input terminals of each fire alarm device (p 24).
Detection zones
Sub-division of a building into detection zones, which are typically protected by a number of manual call points and / or automatic detectors, is recommended for all but the smallest of premises. This is to ensure that those responding to the alarm are directed to the actual location of the fire and is a recommendation even for premises with addressable systems (p 29).
Alarm zones
Many premises have a simple evacuation procedure in the event of fire: when a manual call point or automatic detector is activated, an alarm sounds throughout the building to tell everyone to leave. In some, more complex buildings, however, a phased evacuation policy might be in place, in which case separate alarm zones might be required. In such situations, it is recommended, inter alia, that the boundaries of every alarm zone (other than external walls) are of fire-resisting construction (pp 31–32).
Communication with the fire and rescue service
In order to derive maximum benefit from the fire alarm / fire detection system, it is important that the emergency response services can be alerted as quickly as possible should fire break out. This can be achieved in a number of ways, depending on the category of system installed. In the case of manual systems, which rely on human intervention, a telephone call will suffice. Methods for automatic transmission are divided into four main categories: carrier systems, by means of normal telephone lines; cellular radio communication systems (public or private); private communication circuit systems between the protected premises and alarm receiving centre; and systems that use the public switched telephone network ("digital communicators") (p 34).
Audible alarm systems / visual alarm systems / alarm warnings for people with impaired hearing
It is essential that alarm signals are sufficient in nature and extent to warn all those for whom they are intended. In some situations, e.g. for occupants of a building who have a hearing impairment, it may be necessary to supplement the audible alarm with a visual one, although it is not normally recommended that only a visual alert is used. In premises with sleeping accommodation, e.g. residential care homes, additional, tactile devices, which can be placed under pillows or mattresses and are connected to the fire alarm system, may also be appropriate (pp 36–44).
Manual call points
Manual call points need to be prominently sited, readily distinguishable from non-fire alarm call points, and distributed such that, from any point in the building, it is impossible to leave the storey or building itself without passing one. They must also be sufficient in number to ensure that the time between the discovery of a fire and the alarm being sounded is as short as possible (p 47).
Types of fire detector and their selection
Fire detectors are designed to detect one or more of the four main components of a fire: heat; smoke; combustion gas (e.g. carbon monoxide); and infrared and / or ultraviolet radiation (i.e. flames). As their name suggests, multi-sensor fire detectors contain more than one sensor, each of which responds to a different physical and / or chemical characteristic of fire. The final choice of detector for a particular building will be governed by three main considerations: the speed of detection / response required, as determined by the fire risk assessment / fire safety objectives; the
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need to minimize false alarms; and the nature of the fire hazard. Other issues such as cost and maintenance requirements may also be significant. It is important that all relevant factors are considered at the design stage as there is no one type of fire detector that is suitable for all applications (pp 51–55).
NB The spacing and siting of fire automatic fire detectors is a context-dependent, technical matter for system designers. It is covered in some detail in sub-section 22 of the Standard (pp 56–70).
Control and indicating equipment (CIE); networked systems
Three main functions are performed by centralised CIE: automatic monitoring and control of circuits external to the equipment and the supply of power to them; indication and location of fire / fault signals; and manual controls to enable actions such as routine testing and resetting of the system. The detailed recommendations (pp 71–74) apply to the siting of CIE and the facilities provided for (i) visual indication of fire signals and (ii) control of the system.
In respect of networked systems, the functions of the CIE are not centralized in one location, but are distributed amongst a number of "sub-panels" that are located remotely from each other and interconnected by means of a network that serves as a data highway. Some may act just as "data gathering" panels, while others can be fully functional control and indicating panels with a "stand alone" capability. This means they will continue to operate normally even if the communications link between the sub-panels fails (pp 74–75).
The remainder of Section 2 on design considerations (pp 75–93) covers issues such as power supplies to the system; cables, wiring and other interconnections of the components in a system; radio-linked systems; and electromagnetic compatibility with other electronic equipment (e.g. mobile phones) in respect of both the design and installation. The final sub-section (29) concerns electrical safety. Again, this is technical information for the benefit of the designer and installer, with particular attention drawn to maintenance issues and the need to ensure the adequacy of earthing / protection against shock from exposed metal parts. To this end, diagrammatic illustrations of examples of functional earth follow the detailed commentary and recommendations (p 91).
What are the main installation issues?
Many fire detection / fire alarm systems are highly complex and sophisticated, exhibiting and benefiting from the cutting edge of digital technology, and it is not within the remit of a basic guide such as this to debate the details of the installation process. Apart, perhaps, from the most basic of systems (e.g. one or two manually operated, stand-alone call points in a small, single-storey building), installation is a specialist undertaking and will vary according to the unique characteristics of a particular set of premises.
There are, however, two points of a general nature to note:
Firstly, it is important to ensure that, prior to the installation of a fire detection and fire alarm system, one organisation has accepted responsibility for compliance with the relevant section of BS 5839-1, i.e. Section 4: Installation, pp 108–111. The Standard emphasises this point because it is possible for more than one party to be involved in the process of design through to installation, commissioning and final handover: for example, following on from the fire safety risk assessment, an independent designer may work up the system specifications and then feed them through to another organisation, e.g. a specialist fire alarm or electrical installation contractor, which is to be responsible for supplying and installing the system; or, even in situations where the entire project from start to finish has been commissioned through a single, specialist contractor, the actual installation work could well be sub-contracted out.
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Secondly, it is vital that the selection and siting of each of the fire alarm devices in a system, whether manual, automatic or a combination of both, are such that the possibility of false alarms (pp 100– 107) is limited as much as possible: for example, smoke detectors should never be fitted in kitchens or bathrooms. Page 103 of the Standard gives an overview of the considerations when using point and optical beam smoke detectors, which should be fundamental to the design process, but offers an example of the type of issue which might be picked up and flagged to the designer / user at the installation stage. As a general rule in respect of any design anomalies that may surface during installation of a fire detection and fire alarm system, although the Standard makes it clear that, unless the installer is also the designer, "the identification of design shortcomings is not generally the responsibility of an installer", best practice dictates that "if the installer is aware of such shortcomings, particularly those arising from features of the building that might not have been known to the designer, they be drawn to the attention of the designer, user or purchaser" (p 108).
What happens once the installation is complete?
Pages 112–119 of the Standard cover the commissioning / handover of a fire detection and fire alarm system, which completes the process from initial survey and design through to final signing off of the system as fit for purpose. There are several stages in the post-installation phase, which can be summarised as follows:
Commissioning
The commissioning process involves the thorough testing of the installation to the recommendations of the Standard and to the designer’s requirements (i.e. system specification). The work must be carried out by a "competent person", i.e. one who possesses the relevant current training, experience and capability to perform the task in accordance with all the relevant drawings and reference materials (pp 5, 112).
Documentation
Part of the commissioning process involves ensuring that adequate records and all other relevant documentation have been provided to the end user or purchaser of the fire detection and fire alarm system. Of particular importance are accurate "as-fitted" drawings of the installed system and system-specific operation and maintenance manuals. Other requisite documentation includes: certificates for the design, installation and commissioning of the system; all relevant records, e.g. any agreed variations on the original system design specifications; and a logbook for recording all system events, e.g. fire alarm / fault signals, routine maintenance visits, etc. Annex G (pp 158–160) of the Standard offers a useful logbook template.
Certification
Once a system has been commissioned, certificates must be issued for each of the three separate processes: design, installation and commissioning. Certification can be carried out by a single or multiple organisations but, in all cases, "it is essential that the person who signs these certificates is competent to verify whether the recommendations of this Standard in respect of the process to which the certificate refers have, or have not, been satisfied" (p 116).
Once the certification process has been satisfactorily completed, the system will be formally handed over to the user / purchaser. At this point, it is important that the organisation bearing contractual responsibility for the system issues a certificate of acceptance to the purchaser, for completion by them. Pages 117–118 of the Standard cover the recommendations that apply at this critical stage in the proceedings.
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Annex H (pp 161–168) offers model certificates for all stages of fire detection and fire alarm system work, covering design, installation, commissioning, acceptance, inspection / servicing, and modification. There is also a model verification certificate, confirming overall system compliance with the recommendations of the Standard, which would become relevant should the purchaser or user commission an independent audit of the fire detection and fire alarm system. This usually occurs with larger, more complex installations and is an optional undertaking.
Once the final stages of handover, including certification, have been completed, responsibility for the day-to-day running and maintenance of the system passes to the management of the premises in which it has been installed. There are several aspects to this function, detailed recommendations for which are given in Section 6: Maintenance (pp 120–130) of the Standard. We consider some of the main issues below.
Maintaining the system: what is involved?
No matter how technologically advanced a fire detection and fire alarm system might be with state- of-the-art self-monitoring and automatic fault detection features, there will always be the need for human observation and intervention to ensure its continuous smooth running and optimum performance.
There are three main reasons for routine maintenance and testing:
1. To identify any faults signalled and take the appropriate action to rectify them; 2. To ensure there have been no major failures of the system, either as a whole or in part; 3. To familiarise occupants of the building with the fire alarm signal(s).
As such, it is important for the premises management to institute a schedule of system testing, which can be sub-divided into weekly, monthly and annual routines.
Weekly routine
The Standard makes five detailed recommendations in respect of weekly testing by the user (pp 120–121), which in summary are:
1. The operation of a manual call point during normal working hours; 2. This test to be carried out at approximately the same time each week; 3. Additional tests to be made at least once a month for any employees not usually present
during the normal weekly test; 4. In systems with multiple manual call points, a different one to be tested each week, so that
all are eventually included in the schedule of testing over a period of time; 5. The routine test time should not normally exceed one minute, so that the occupants of the
premises can learn to distinguish between this weekly alarm and an actual fire alarm.
In respect of voice alarm systems, the Standard recommends that these are tested weekly in accordance with BS 5839-8.
Monthly routine
The Standard applies two detailed recommendations for monthly testing by the user (p 121), which can be summarised as follows:
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1. If the standby power supply to the system includes an automatically started emergency generator, this should be tested monthly;
2. If the standby power supply is provided by vented batteries, these should be inspected visually. Furthermore (p 122) all vented batteries and their connections should be examined on a quarterly basis (i.e. every three months) by a person competent in battery installation and maintenance technology.
Inspection and servicing
Over and above the weekly and monthly test routines, it is important for regular inspection and servicing of the system to be carried out, in order to identify and rectify any faults, including false alarm problems, and also to ensure that any changes made to the actual fabric of the building, e.g. extensions, alterations or remedial work, that might have been made in the meantime have not affected the system in any way, either through damage to any of its elements or by impacting on the level of protection it offers. Changes in use and / or occupancy levels of a building can also have a detrimental effect on the protection offered by existing fire protection and fire alarm systems so any such factors must also be taken into consideration during the inspection process. The recommended period between successive inspection and servicing visits should not exceed six months.
Because of the specialist nature of the work, inspections are usually contracted out to a fire alarm service organisation, whose competence can be assured by third-party certification.
Functions included in the periodic inspection and testing of the system include, inter alia, an examination of the logbook, to include follow-up action on any faults recorded, and a visual inspection of all the manual call points, automatic fire detectors and fire alarm devices, with particular regard to any changes in building structure, occupancy levels and / or use, as noted above. Pages 122–123 of the Standard apply detailed recommendations to the various aspects of periodic system inspection and testing, with recommendations in respect of additional tasks that should be carried out annually (pp 123–125). As this is a labour-intensive undertaking, it is noted that some elements of the work can be spread over two or more service visits during each twelve-month period (p 123).
In respect of non-routine attention to the system (pp 126–130), there are several scenarios that can arise and to which the Standard applies detailed recommendations. These range, inter alia, from the appointment of a new servicing organisation (which will necessitate a special inspection of the system) through fault repair and system modifications to inspection and test of the system following any fire.
User’s responsibilities and premises management: who does what?
A fire detection and fire alarm system is designed to protect life and / or property, as discussed in part 1 of this entry-level guide to the Standard. In order to fulfil this function, it is vital that maintenance, inspection and testing of the system are carried out on a regular, scheduled basis.
It is a complex process that can involve several different parties, so the Standard recommends that the system user appoints "a single, named member of the premises management to supervise all matters pertaining to the fire detection and fire alarm system". This places responsibility firmly in the hands of one individual, whose role is "to ensure that the system is tested and maintained in accordance with the recommendations of (Section 7: User’s responsibilities) of BS 5839" (p 131).
These responsibilities include, inter alia: the keeping of appropriate system records and all relevant documentation; ensuring that all relevant occupants of the protected premises are aware of any specific role and / or responsibility assigned them in respect of the fire detection and fire alarm
9
system; and that the system itself is protected from any development that might negatively impact on the standard of protection it offers and / or contribute to the incidence of false alarms.
The logbook is a key document and, as well as the details of the manager / supervisor to whom responsibility for the fire detection and fire alarm system has been delegated, should contain a record of all the events that concern the system, whether these occurrences were scheduled or not (e.g. routine maintenance visits, test signals, fault signals, etc.). This comprehensive information can be valuable to whoever services the system and might also provide evidence of compliance with certain aspects of fire safety legislation, should such need arise.
References:
http://www.safelincs.co.uk/a-summary-of-the-bs5839-1-2013/
http://www.oheap.co.uk/fire-alarm-emergency-lighting-systems/design-
installation/#StageTwoDesign
__MACOSX/._5c. Summary of the BS 5839- notes.pdf
5e. Locating Emergency Lights- notes.pdf
1
1
Fire Safety in the Built Environment Module 6FF011
Note 5e Locating Emergency Lights
Emergency lighting is designed to provide sufficient illumination in the event of a mains power
failure. The guide below provides examples of where to locate your emergency lighting according to
different areas of premises. As well as highlighting the fire exits of a building, correctly located
emergency lighting provides essential illumination throughout the escape route including steps and
stairways, changes in direction and fire and first aid points.
Changes in Direction
It is important to have emergency lighting that clearly illuminates corridors and where there are
changes in direction. This allows users to clearly identify their means of escape and should highlight
the escape route signs.
Stairways
2
2
Stairways and stairwells can present a potential hazard in an emergency. Emergency lights need to
be fitted so that all of the stairs declines and inclines are made visible.
Steps and Ramps
In areas where flooring may become uneven on an escape route, a lighting unit should be fitted to
so that it does not prove a danger to users. Uneven flooring can consist of single steps, ramps,
sloping floors etc.
Fire & First Aid Points
Fire and first aid points can prove essential in the event of an emergency. Emergency lighting should
be installed to highlight the fire-fighting and first aid equipment so that they can be located with
ease even after a mains failure.
3
3
Exit Doors (External & Internal)
Ensuring that exit doors are well lit in an emergency can be the difference between evacuating a
building and getting trapped inside. All exit doors need to be well lit to ensure that users can identify
where to go at the end of escape routes.
Escalators
Whilst escalators should not be a part of any escape route it is still a requirement to provide
illumination of them in an emergency. By making them visible, the chances of escalators becoming
hazardous are significantly reduced.
4
4
Lifts & Elevators
Installation of emergency lighting in lifts is essential even though they are not to be used on an
escape route as users may be in the process of using the lift when evacuation is required. When the
main power to the lighting units is cut there needs to be sufficient illumination for users to react.
Toilets
Emergency lighting needs to be provided in all areas of a premises where staff and members of the
public have access to. Emergency illumination in toilet areas allows occupants to safely make their
way to the escape route and helps to avoid a panic situation.
5
5
Generators
High risk areas within a building can be defined as those which require users to demonstrate
additional amounts of care. The importance of having sufficient lighting, especially in an emergency,
is therefore heightened.
Large Open Areas
Areas accessible by the public that are larger than 60m
2 and open areas with an escape route
running through them must have emergency lighting installed to ensure users safety, guiding them
to the nearest exit.
Reference
http://www.safelincs.co.uk/location-of-emergency-light-units/
__MACOSX/._5e. Locating Emergency Lights- notes.pdf
8. Fire Engineering-Lecture.pdf
© Artemis 2016
Fire Safety in the Built
Environment
Module 6FF011
Rory Campbell
© Artemis 2016
Session 8-
Fire Engineering
and
Fire Engineered Solutions
© Artemis 2016
Objectives
• After studying this module, students will: – Have an improved understanding of the meaning and
purpose of fire engineering
– Be able to explain how fire engineered solutions are
used to protect occupants from fire
– Understand the elements of a fire engineered
package of measures, including
• Sprinklers and intelligent alarm systems; PAVA
• Phased evacuation protocols
• Smoke and heat extraction
– Understand the applications where engineered
solutions are typically applied
© Artemis 2016
Active / passive protection
• Passive protection
includes building
features to protect
occupants:
– FR construction
– Exits
– Protected routes
– Compartmentation
– Travel distances
• Active protection uses
tech systems to
support safety:
– Smoke and heat
extraction (SHEVS)
– Pressurised routes
– CCTV, PAVA
– Fire shutters and
curtains
– Intelligent alarms
– Life safety sprinklers
© Artemis 2016
Fire philosophy
• Overall, many
features and systems
combine to work
together
• Complex buildings
can be protected
through a rationale
• Based on a range of
potential scenarios
• Likely events can be
predicted and
planned for
• Fire conditions can be
modelled and
simulated
• Structures designed
around performance
expectations
© Artemis 2016
FRS intervention
• We can assume that
the FRS will respond
and attack the fire
• Facilities are
incorporated, for FRS
tactical actions
– Access
– Water supplies
– Smoke protection
© Artemis 2016
Why fire engineering?
• Approved Document
B shows how to meet
the requirements of
B/Regs
• Categorises buildings
by purpose groups
• Regulates:
– Travel distances
– Exit numbers
– Staircases
– Width of routes etc.
© Artemis 2016
Complex structures
• Too restrictive to
apply ADB to some
buildings:
– Too large
– Too complex
– Mixed purpose groups
• Designer wants to
incorporate features:
– Atrium
– Open malls
– Concourses
© Artemis 2016
Benefits of FE design • Uses technology to compensate for:
– Increased travel
– Narrower exit routes
– Less staircases
– Open plan spaces
– Smoke handling
– Mixed occupancies
© Artemis 2016
Some
examples....
© Artemis 2016
© Artemis 2016
Phased evacuation • Intelligent fire
detection and alarm
• Allows evacuation to
be programmed into
scenarios
• Alarm may only
sound in fire
compartment
• Nearby zones may
go to ‘alert’
© Artemis 2016
CCTV
• CCTV can be used
for security, but also
for fire detection
• Software system
enables fire
recognition
• Raises alarm
http://argosfire.co.uk/spotfire-fire-spotting-
camera/
© Artemis 2016
Smoke control • Shopping malls rely
on extraction of hot
smoke and gas from
a fire
• Smoke rises to roof
level
• Sprinklers control fire
development
• SHEVS extracts
smoke
• People have time to
escape
© Artemis 2016
Smoke control • Relies on software
modelling of fire
plume and smoke
travel
• Computational fluid
dynamics (CFD)
• Based on standard
fire size and heat
output
• Height of ceiling
increases available
time
© Artemis 2016
CFD
• Predicts fire growth
rate
• Calculates
temperatures
• Runs numbers of
simulations
• Demonstrates travel
of heat and smoke
• Suggests limits of
tolerability
http://www.fireng.org/p/introduction-to-
fire-modelling.html
© Artemis 2016
SHEVS
• CFD allows use of
smoke and heat
extraction systems
• Rated to correct
capacity for
anticipated volumes
of smoke
• Relies on air inlet at
lower levels
• Takes smoke from
reservoirs
© Artemis 2016
Extraction fans
• Mounted at high level
• Withstand extreme
temperatures
• Extract large volumes
of smoke and gas
• Protect escape routes
• Run to destruction
• Require air inlet
http://www.coltinfo.co.uk/smoke-
ventilation.html
© Artemis 2016
SHEVS • Can be used to pressurise areas around fire
compartment and stairways or escape routes
• Keeps non-fire areas smoke free for escape
http://www.kmccontrols.com.hk/products/smoke_control.html
© Artemis 2016
Compartmentation
• Fire resistance
between
compartments
• Can be supplemented
by automatic curtains
and shutters
• Controls smoke travel
• Reduces entrainment
of air into smoke
plume
• Protects escape route
© Artemis 2016
PAVA • Alarm incorporates a
public address
system
• Uses voice alarm
messages rather than
bell / siren
• Gives instructions to
occupants, zone by
zone
• Alert / alarm / clear
© Artemis 2016
Safe egress time
• Fire engineering
relies on the
calculation of safe
egress time
• Compare available
safe egress time
(ASET) with required
safe egress time
(RSET)
• ASET must be
greater than RSET
• Safety margin is
applied
• ASET determined
through use of CFD
modelling
• Depends on tenability
parameters:
– Temperatures
– Atmosphere
– Visibility
© Artemis 2016
ASET > RSET
© Artemis 2016
Approaches to fire safety design
1. General approach
2. Advanced approach
3. Fire engineered
approach
• General approach:
– Straightforward
– Follows guidance
– AD B
– Purpose groups
– May be too narrow for
some building types
© Artemis 2016
Advanced approach
• Looks at individual
characteristics of
– Building
– Occupants
– Activities
• Relies on use of BS
9999
• Requires some fire
safety knowledge
• Builds a risk profile
• Allows trade-offs
between travel
distances etc and
adoption of alarm
system, sprinklers...
© Artemis 2016
Fire engineered approach
• Uses BS 7974
• Requires specialist
knowledge and skills
• Mixed use buildings
– Very large spaces
– Complex design
– Fire philosophy
– Structured analysis
• Relies on interaction
of sub-systems
• BS is backed up by
range of published
documents- PD’s
• Uses probabilistic risk
assessment
© Artemis 2016
Case Study
Birmingham Bullring Centre
© Artemis 2016
Bullring-
Overview • Enclosed shopping complex
on 11 levels
• Over 100 shop units with 1.2
million square feet of retail
space
• Selfridges & Debenhams
anchor stores
• Basement service area
• 1000 space basement car park
on 2 levels
• Very large atrium design
building
© Artemis 2016
Fire Engineering Provisions
• Emergency lighting & fire signage
• Means of warning &
escape
• L1 Automatic fire
detection system with
PAVA (public address
voice alarm)
• CCTV
• Rapid response
sprinklers throughout
• Zoned evacuation &
smoke control system
• Disabled intercoms to
refuges
© Artemis 2016
• Internal fire spread
• Drencher system to
compartment walls
• Fire shutters to provide
compartmentation
• Access & facilities for the
fire service
• Management control
centre
• Fire fighting shafts -
pressurisation system
© Artemis 2016
Firefighting shafts
• Fire protected
stairway
• Firefighting lift
– Power source
– Control switch
– Lighting
• Firefighting lobby
– Dry riser outlet
– Vent shaft or opening
– Maybe pressurised
– Comms
© Artemis 2016
Smoke vents and pressurisation
© Artemis 2016
Sprinklers
© Artemis 2016
Control room; PAVA
© Artemis 2016
Your task...
You will be given a task to research and
report back on, working as a member of a
team.
You must present the findings of your
research and discussion to the group as a
whole, at the end of the session.
__MACOSX/._8. Fire Engineering-Lecture.pdf
8a. Fire Safety Design guidance- BS 9999.pdf
1
Fire Safety in the Built Environment Fire Engineering: BS 9999 Artemis TDL 2016
Fire Safety in the Built Environment Module 6FF011
Note 8a Fire Safety Design Guidance
BS 9999:2008, Code of practice for fire safety in the design management and use of buildings.
Introduction
The fire safety requirements for new and existing buildings are continually being updated. In October 2008 a new UK guidance document came into effect covering a whole range of fire related issues associated with buildings. This note informs on the key areas which may affect a design, with particular emphasis on benefits (and limitations).
Background
There are a number of approaches which can be used to meet the Building Regulations requirements for fire safety:
1. The Primary guidance for fire safety is Approved Document B (England and Wales), Technical Booklet E (Northern Ireland), Scottish Technical Standard (Scotland) and Technical Guidance Document B (Ireland). These guidance documents provide basic advice for most buildings; however it is limited in detail and only provides general fire guidance. If a design does not comply with the guidance documents, a more detailed assessment would be recommended;
2. The next tier of guidance is typically British Standards and other internationally recognised design documents. BS 9999 now supersedes the BS 5588 series (excluding Part 1 for Apartments) and is regarded as an advanced approach. This new guidance is a consolidated document which covers detailed design requirements and is broadly based on sound fire engineering principles. This new standard encompasses designs of atriums, shopping centres, commercial premises, storage/warehousing, car parks, industrial and manufacturing buildings that were previously dealt with in separate standards.
3. BS 9999 can be viewed in some shape or form as a prescriptive based approach employing performance based fire engineering techniques. Fire Engineering has been used features as sprinklers, smoke/heat ventilation, high ceilings etc to provide extra time and safety to people when escaping from fire, however this was not readily acknowledged in the guidance documents noted in 1 above.
BS 9999 takes a step closer to performance based engineering and recognises such benefits, and allows longer travel distances, smaller exit and stairs widths, etc when added or enhanced forms or safety measures are included.
4. Whilst acknowledging that BS 9999 takes this important step there are inevitably design solutions which can benefit from a performance based approach. Fire Safety Engineering can be used as an alternative approach and is often the only practicable way to achieve a satisfactory standard of fire safety.
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Fire Safety in the Built Environment Fire Engineering: BS 9999 Artemis TDL 2016
BS 9999 Overview
Purpose Groups are related to Occupancy Characteristic & Risk Profile. The installation of sprinklers for example reduces a risk profile from say a high risk category to a medium risk category, and therefore, by doing so, is afforded all the added benefits, such as longer travel distances, narrow exits and stairs, reduced structural fire ratings, and so on.
Management is a key area of the new guidance. Designers should ensure that specific management requirements can be adopted within the building, which are not unduly restrictive.
B1: Means of Escape
Egress calculations were previously based on the use of 5mm/persons. This was used to calculate exit and stair widths. This single design value has now changed to a number of various width factors depending on the risk profile.
In addition to this, where sprinklers or smoke ventilation are used or high ceilings are proposed these exit factors can allow extended travel distances (10-25%), narrow exits and stairs (up to 75% reduction), as well as less exits and stairs.
When measuring travel distance, measurement to another compartment exit in the same building, is now recognised.
In terms of fire detection and alarm systems, purpose groups such as offices need only be provided with break glass units, i.e. no smoke/heat detection. If detection is provided narrower exits or stairs, extended travel distances and so on are feasible.
Single exits and direction of opening can accommodate 60 persons. The minimum door width regardless of numbers is 800mm clear width (taking into account door hardware, such as handles).
With regard to critical minimum stairs sizes, there are some set rules, i.e. minimum stair width of 1000mm generally (increased to a minimum of 1100mm for assembly buildings) for stairs above ground and 1200mm for stairs below ground (i.e. basements) generally.
The widths of corridors shall be same as doors leading to it, or 1200mm, however may be reduced where no wheelchair users or for areas just used for maintenance.
Crèches should be a near or located at ground level and provided with at least two exits.
There are additional precautions relevant to mezzanines or galleries.
All smoke vents should be located at least 3m from an escape route.
Theatres, Cinemas, Shopping Centres have no significant changes.
B2: Internal Fire Spread (Linings):
Generally BS9999 provides no significant change in this regard. There is a new limitation on materials in small rooms (<4m
2 ) in residential buildings. There is a new classification, Class 3 / Class D-s3, d2 in
non-residential rooms less than 30m 2 and domestic garage less than 40m
2 .
B3: Internal Fire Spread (Structure):
There are some significant changes in B3 as follows:
The fire resistance of structures where ventilation can be considered for potential openings (i.e. glazing braking during fire) is reduced.
If sprinklers are provided the fire resistance of structure can be reduced.
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Fire Safety in the Built Environment Fire Engineering: BS 9999 Artemis TDL 2016
Un-sprinklered open sided car-parks greater than 30m in height are now permitted.
All other buildings, regardless of their risk profile, greater than 30m in height are to be sprinklered.
There are compartment limits dependant on single or multi-storey buildings (and height of multi-storey), but no limit on compartment volume.
Generally, there are increased compartment limits, but some areas such as retail are smaller if multi-storey. However, as noted earlier, sprinklers would change the profile allowing increased limits.
Where basements are deeper than 10m, each floor would need to a compartment floor. This will affect multi-level basement car parks.
B4: External Fire Spread:
There is no restriction on distance between small unprotected openings (1m 2 ) between
compartment floors or walls.
Unprotected areas for areas greater than 30m above ground in large un-compartmented buildings can be discounted (i.e. halls, or atria type entrances).
1.8m wide fire protection to external walls at angles with stairs extends to all protected escape routes, e.g. corridors, etc. The fire protection to an access corridor to a Fire Fighting shaft is increased to 5m.
Classification of external surfaces broadened to Class 0 / 1 dependant on proximity to boundary and height. 18m.
B5: Access & Facilities for the Fire Service:
In general, there are no significant changes from BS 5588-5: 2004. The extent of fire tender access related to total floor area of the building. Note: this does not exclude basements. These is however a change to the measurement of a height of a building, which previously indicated that it was the height from the lowest ground level floor to the highest storey (excl plant), but now, can be measured from the level of the fire service access.
Wet mains (i.e. including tanks and pumps) are needed to buildings with a top floor >50m above fire service access level. There is some reduction in areas of vents to stairs, but increases to lobby ventilation direct to open air to 1.5m
2 . Ventilation to Fire Fighting stairs highlights a limitation of 30m
top floor, which is in line with the study of the effectiveness of natural vents at such heights.
__MACOSX/._8a. Fire Safety Design guidance- BS 9999.pdf
8b. Fire Engineering and BS 7974.pdf
1
Fire Safety in the Built Environment Module 6FF011
Note 8b Fire Engineering and BS 7974
Application of fire safety engineering principles to the design of buildings - Code of practice
This British Standard provides a framework for an engineering approach to the achievement of fire safety in buildings by giving recommendations and guidance on the application of scientific and engineering principles to the protection of people, property and the environment from fire. It also provides a framework for developing a rational methodology for the design of buildings.
This standard applies to the design of new buildings and the appraisal of existing buildings. The use of this standard will facilitate the practice of fire safety engineering and in particular it will:
1. provide the designer with a disciplined approach to fire safety signs; 2. allow the safety levels for alternative designs to be compared; 3. provide a basis for selection of appropriate fire protection systems; 4. provide opportunities for innovative design; 5. provide information on the management of fire safety for a building.
This standard does not provide specific guidance on buildings used for the bulk storage or processing of flammable liquids or explosives. The intrinsic risks associated with such buildings will often necessitate special consideration, which is beyond the scope of this document.
Associated Guidance
PD 7974-1:2003: Application of fire safety engineering principles to the design of buildings; Buildings; Design, Safety engineering; Structural fire protection; Fire spread prevention; Means of escape from fire in buildings; Enclosures; Ignitability; Fire stops.
Application of fire safety engineering principles to the design of buildings. Initiation and development of fire within the enclosure of origin (Sub-system 1)
This Published Document provides guidance on evaluating fire growth and/or size within the enclosure of fire origin, as well as enclosures to which the fire has subsequently spread. Guidance is also provided for “special cases” which include malicious fires, racked/stacked storage of goods and fires external to the building.
The characteristics of the design fire for any particular scenario are influenced by a number of factors, including building design, environmental influences, potential ignition sources and location, types of combustible material distribution and arrangement of combustible materials, ventilation conditions and other events occurring during the fire.
The determination of the characteristics of the design fire from ignition through to decay is used by other Sub-systems as inputs into calculations of events such as time of fire spread from enclosure [PD 7974-3 (Sub-system 3)] and time to activation of suppression systems [PD 7974-4 (Sub-system 4)].
2
PD 7974-2:2002: Application of fire safety engineering principles to the design of buildings. Spread of smoke and toxic gases within and beyond the enclosure of origin.
Application of fire safety engineering principles to the design of buildings. Spread of smoke and toxic gases within and beyond the enclosure of origin (Sub-system 2)
This Published Document provides guidance on the application of fire safety engineering principles for the treatment of smoke movement, control and management problems. The guidance is intended primarily for professional engineers with a responsibility for the design or assessment of fire safety in buildings.
Sub-system 1 (PD 7974-1) provides information on the rate of production of heat and combustion products from the fire source. The aim of Sub-system 2 is to provide design approaches to estimate the spread of the combustion gases within and beyond the room of origin and to evaluate their properties, i.e. temperature, visibility and concentration of toxic products. This information can be used to calculate the time between the detection of a fire to conditions developing which would be dangerous to building occupants. This will enable the design of fire safety measures to ensure that sufficient time is available for escape. It also provides information that will allow property issues to be assessed.
This Published Document forms part of a series of Sub-systems 1 to 6 (PD 7974-1 to PD 7974-6), but may, in consultation with the appropriate references, be regarded as “stand-alone” guidance.
PD 7974-4:2003: Application of fire safety engineering principles to the design of buildings. Detection of fire and activation of fire protection systems
Specification of fire safety engineering principles to the design of buildings. Detection of fire and activation of fire protection systems.
This Published Document provides guidance on the development, design and application of fire detection systems, and the activation of fire alarm and fire control systems to fulfil a role in the fire safety engineered design for a building. Scientific and engineering principles are used as part of a structured approach. The key elements covered are:
detection: information is provided on the various types of fire detection system and their application for a given set of circumstances, as derived from a qualitative design review, risk assessment and the results of formulae provided by other Sub-systems;
activation and control: once the fire detection system has detected a fire, it activates a series of measures designed to fulfil the requirements of the fire safety engineered design. These measures may include operation of fire warning systems, the remote signalling to emergency services, and the operation of fire alarm, fire suppression and fire control systems. Guidance is given on the methodology and formulae required in ensuring that the appropriate systems are activated in an appropriate manner and within given criteria.
In the context of this document, fire control includes:
fire suppression systems: active systems designed to suppress a fire, temporarily (i.e. control) or permanently (i.e. extinguish). Examples include automatic water sprinkler systems;
3
fire barrier systems: active systems designed to contain a fire within a given area or separate a fire from another area. Such systems may be regarded as offering similar benefits to passive fire compartments or separations for the duration of their operation. Examples include fire damper systems and door release mechanisms;
smoke/heat control systems: active systems designed to positively control the movement and build up of fire effluents such as smoke, heat and toxic gases. Examples include smoke venting systems and air pressurization systems.
PD 7974-5:2002: Application of fire safety engineering principles to the design of buildings. Fire service intervention.
Application of fire safety engineering principles to the design of buildings. Fire service intervention.
This Published Document provides guidance on fire service intervention and evaluates the rate of build-up of fire-fighting resources of the fire service. These activities may include in-house or private fire brigades, and, in particular the time interval between the call to the local authority fire service and the arrival of the fire service at its predetermined level of attendance. The time interval between the arrival of the fire service and the start of their attack on the fire are covered, together with the time intervals related to the build-up of any additional fire service resources and the extent of fire-fighting resources and extinguishing capability available at various times.
This Published Document takes information on building characteristics and the design fire from the Qualitative Design Review (QDR), together with the time of fire service notification from Sub-system 4 (PD 7974-4) and the time of evacuation from Sub-system 6 (PD 7974-6). It provides information on the effect of fire service activities on the growth of the fire, which is used by Sub-system 1 (PD 7974- 1).
PD 7974-6:2004: The application of fire safety engineering principles to fire safety design of buildings. Human factors. Life safety strategies. Occupant evacuation, behaviour and condition.
The application of fire safety engineering principles to fire safety design of buildings. Human factors. Life safety strategies. Occupant evacuation, behaviour and condition
PD 7974-6:2004 is intended to provide guidance to designers, regulators and fire safety professionals on the engineering methods available for the evaluation of life safety aspects of a fire safety engineering design in relation to evacuation strategies.
Should a fire occur in which occupants might be exposed to fire effluent and/or heat, the objective of the fire safety engineering strategy is to ensure that such exposure does not significantly impede or prevent the safe escape (if required) of essentially all occupants, without their experiencing or developing serious health effects.
Advice is presented on the evaluation and management of occupant behaviour, particularly escape behaviour, during a fire emergency and for the evaluation of occupant condition, particularly in relation to exposure to fire effluent and heat.
4
This Published Document addresses the parameters that underlie the basic principles of designing for life safety and provides guidance on the processes, assessments and calculations necessary to determine the location and condition of the occupants of the building, with respect to time.
This Published Document also provides a framework for reviewing the suitability of an engineering method for assessing the life safety potential of a building for its occupants.
PD 7974-7:2003: Application of fire safety engineering principles to the design of buildings. Probabilistic risk assessment.
Application of fire safety engineering principles to the design of buildings. Probabilistic risk assessment
This Published Document provides guidance on probabilistic risk analysis in support of BS 7974, Application of fire safety engineering principles to the design of buildings — Code of practice . It sets out the general principles and techniques of risk analysis that can be used in fire safety engineering. This Published Document also outlines the circumstances where this approach is appropriate and gives examples illustrating their use.
This Published Document also includes data for probabilistic risk assessment and criteria for assessment. The data included is based on fire statistics, building characteristics and reliability of fire protection systems. The criteria included cover life safety and property protection, both in absolute and comparative terms.
This Published Document does not contain guidance on techniques for hazard identification or qualitative risk analysis.
Probabilistic risk assessment of fire in buildings (with the exception of nuclear, chemical process, offshore and transport) is not widely used and so a discussion of possible future developments is included.
References
http://www.solutionsfiresafety.co.uk/BS7974-2001.html
http://shop.bsigroup.com/ProductDetail/?pid=000000000030028692
http://www.firesafe.org.uk/fire-safety-in-new-extended-or-altered-buildings/
__MACOSX/._8b. Fire Engineering and BS 7974.pdf
9. FRS Facilities- notes.pdf
1
Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Fire Safety in the Built Environment Module 6FF011
Note- 9
Facilities for the Fire and Rescue Service – Access; Water supplies; Firefighting Equipment
A number of issues have to be considered when planning to build any new structures in the UK, whatever is
being considered- from a new housing development through to a skyscraper or a multi-million pound shopping
centre or a giant high-bay storage and distribution warehouse.
Some of these considerations have already been described in the notes on the planning and building control
process, but we will expand on those details here, to cover the range of factors to be examined with regard to:
Access for fire fighting vehicles
Supply of water for firefighting
Fixed installations required in large or tall buildings
o Firefighting water, including dry and wet risers and falling mains, tank supplies
o Sprinklers, drenchers etc- active systems
o Alarm systems
o Emergency lighting
o Fire ventilation
o Basement vents and foam flooding systems
o PA systems and other communications hardware
o CCTV and visual information from control rooms
Dedicated firefighting shafts
o Stairway
o Lobby
o Riser outlets
o Smoke vents and vent shafts
o Pressurisation systems
o Firefighting lifts
Control
Fire resistance
Power supplies
Lighting
Escape hatch
Disabled refuges
o Comms
o Escape / evacuation chairs
Plans and keys
Specialist equipment
o Foam making and delivery
o Specialist PPE for specific sites
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Planning Control- Water supplies and access
When a developer intends to build a new development, the first requirement is to apply to the local authority
(LA) for planning consent.
This gives the LA a chance to require certain features and to impose limitations as they see fit, but they must
also allow the FRS to comment on the plans and take note of relevant comments made.
The built environment has to be served by an adequate water supply by the local undertaker (ie. supplier) and
this serves not only for normal domestic / industrial purposes, but also for firefighting, as water from the local
town main is the first port of call for many firefighting operations. There are guidelines laid down, as to the
dimensions of the fire main required, together with pressure and flow rates and we will not concern ourselves
with the details here.
But for a new development, an assessment has to be made as to whether the existing ring main is sufficient for
the proposal, or whether it will need to be upgraded.
Open Water
Whenever a new development is planned to locate adjoining an open water source, then access to that water
should be provided for firefighting vehicles, so that it can be used for firefighting when necessary.
Fire fighting access to
water must be made
available, with suitable
hard standing for fire
pumps, in any
waterfront
development.
The FRS must be
consulted at the
earliest stage.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Hydrants
Hydrants are fitted onto the water main to enable water to be taken for firefighting purposes. There is guidance
to outline how frequently these facilities should be supplied, according to the risk:
Nature of development
Distribution
Town centre redevelopment; open plan; low rise or high rise
90m apart
Industrial area 150-200m apart
Residential area 250-300m apart
Rural area No more than 500m apart
The design of hydrants is laid down in British Standards and their location needs to be marked by a standard
signpost.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Housing
Developments of units with detached or semi-detached houses of not more than two floors should have a water
supply capable of delivering a minimum of 8 litres per second through any hydrant on the development.
If the development is more than two floors, the supply should be capable of delivering 20-35 litres per second
through all hydrants.
Industrial development
Lorry and coach parks, multi-storey car parks and service stations must have a supply of 25lires/second and
hydrants must be within vehicular distance of 90m from the complex (ie. approximately four lengths of FRS
delivery hose).
http://www.saint-gobain-
pam.co.uk/water-sewer/valves-
hydrants/hydrants/
https://www.suffolk.gov.uk/suffolk-fire-
and-rescue-service/fire-safety-in-the-
community/fire-hydrants/
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
The water main supplying an industrial development should usually be at least 150mm diameter and according
to the size of the development, should have the following supply capabilities:
Size of development
Required flow
Up to 1 hectare 20 litres/second
1-2 Ha 35 l/sec
2-3 Ha 50 l/sec
>3 Ha 75 l/sec
Similar tables are given for the requirements relating to shops, offices and recreation, or education and health
developments.
In rural areas this may not be possible, so static or river supplies may be acceptable, if they are able to satisfy
acceptable flow rates for one hour.
High risk units may require greater flow rates.
Access for vehicles
Vehicular access must be considered at the planning stage and as FRS vehicles are generally larger than those
for Police and Ambulance services, then sufficient access for the FRS will satisfy other services by default.
As an example of this, there is a requirement that no new cul de sac shall be more than 180 metres in length
unless it is supplied with emergency vehicular access for fire engines. Where a dead end road is more than 20m
long, it must be provided with a suitable turning circle or hammerhead at the end or within 25m of the end of
the road, so that a fire engine as able to turn around rather than have to reverse from the road. Other
requirements describing road widths, radius of corners, camber etc are standard for any usage by vehicles such
as refuse lorries and will suffice for FRS access.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
There are limits laid down
for the angle of
hammerheads and turning
facilities for vehicles in new
developments and fire
engines form part of these
considerations
Bridge doors are a common sight in
some cities where access for
firefighting water can be obtained
by unlocking the small wooden
door and setting up suction hose,
to draw water from a canal
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
The minimum width of FRS access roads is 3.7m and if necessary, an access road can be protected from
unauthorised usage by other vehicles, by posts or gates fitted with a padlock.
Smaller buildings with a top storey below 9m above ground will need to allow vehicle access to within 45m of an
access door. This is to ensure that FRS hosereels can be brought into use to support a rapid fire attack or rescue.
Approved Document B also covers access to buildings and specifies the degree of FRS access required in new
buildings. Part B5 describes how access is needed for FRS vehicles and for personnel to have sufficient space and
facilities to allow them to fulfil their function of firefighting and rescue work.
Requirements are given for fire hydrants and in tall buildings, firefighting mains (dry or wet risers). Where fire
mains are not provided and would normally be required, then it may be satisfactory to provide a static tank
supply of 45 000 litres, or a similar capacity form a river or pond.
http://www.southportgb.co.uk/
Fire access may be needed to
open water pumping sites such
as a canal or pond, with suitable
hard standing to take the
weight of an FRS appliance
without the danger of it getting
bogged down and stuck in mud
etc.
Turning tee is provided for FRS vehicles
in new road developments, based on the
size and turning circle of a typical FRS
pump.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
ADB part B5 gives details of the level of access required to buildings, including aerial appliances (‘High reach’) at
those buildings over a certain size.
Access can be required to several
faces of a building during fire
and rescue operations, and
requirements for this access are
contained in ADB B5.
This can apply not just to fire
engines but also aerials or high
reach vehicles, weighing much
more and possibly needing
dedicated access roads.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Firefighting Shafts
The intention is that every part of the floor area in a building can be reached within a reasonable length of
firefighting delivery hose, either from the pump or from a riser outlet instead. It may then be necessary for that
riser outlet to be in a protected lobby to enable firefighting and rescue operations, particularly if the building is
not fitted with sprinklers.
Part B5 of ADB details how buildings over
a certain size, height, or with a large
basement, may need to be fitted with a
firefighting shaft which may in turn
require a firefighting lift.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Diagram (above) is from ADB showing situations where a firefighting shaft is necessary in a new building.
Diagram above is from ADB showing required structural layout of a firefighting shaft
A firefighting shaft is a fire protected structure that allows firefighters to walk or use a lift up to the fire floor (or
a suitable floor below) and gain access from an area of safety. The shaft will be ventilated either by opening
vents in the external wall, or a doorway into a second shaft provided for the purpose (or in some cases, the
staircase may need to be pressurised).
Thus, firefighters are able to reach an appropriate location to establish a base for
an operational attack on the fire, or for rescue purposes, in the knowledge that
the bridgehead so established will not be compromised by the spread of fire and
smoke.
In addition, there has to be a water supply, from a rising main- either dry or wet. If
dry, the main is charged by the fire service pump at ground level, before the fire
attack is mounted. If there is a wet main (in very tall buildings this is a
requirement) then the main is constantly charged from a combination of sources-
normally a static tank at high level and backed up by the street main, with no need
for fire service charging of the pipe.
Outlets from the main are found at every floor level, within a firefighting lobby.
The lobby is a space between the stairs and the accommodation area, protected
by fire doors.
Diagram from
ADB showing
elements of a
firefighting
shaft
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Controls provided for smoke vents in the firefighting shaft.
Firefighting lifts
Lifts must be provided for firefighting in very tall or large buildings, where access would otherwise be difficult.
There are a number of features to a firefighting lift which distinguish it from a standards lift and these are
contained in the European Standard BS EN81-72.
Fundamental firefighting elevator requirements : Minimum car size 1100 x 1400 mm, 630 kg • Minimum door
width 800 mm • Elevator must reach the farthest floor from the fire service access level within 60 sec. • Trap
door required, minimum 400mm x 600mm for 630kg, and 500mm x 700mm for larger cars • Electrical
A manual smoke vent can be
incorporated into the head of
the firefighting shaft, to assist
with keeping it free of smoke
during a fire.
Picture below shows smoke vent
doors either to external or into a
smoke vent shaft
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
equipment accessible to firefighters either IPx3 rated or protected against splashing water, as specified in EN81-
72.
Basically, the lift must have a secure source of power to prevent personnel becoming stranded in the lift car. It
has to be protected against splashes of water and needs to have a hatch in the ceiling for rescue by ladder if
necessary. The controls must be able to be over-ridden by FRS personnel armed with a key and there will be a
communication system fitted. Door controls fail to safety when the key has been actuated to prevent accidental
opening of lift car doors onto a smoke-filled fire floor.
Pressurised stairways and pressurisation systems
If the firefighting shaft cannot be vented to fresh air or via an internal smoke shaft, it may be rendered safe
through the use of pressurisation.
This means that a system of fans and ducting is built into the structure, so that in the event of fire, air is pushed
into the protected area, forcing it out of the stairway and lobby. In this way, smoke will not be entrained into
the relevant areas, but any smoke contamination will be held back by the slight pressure differential.
For this to succeed, there must be a leakage path, so this is one instance when the fire doors should not be
fitted with smoke seals, as there will need to be leakage from the clean side into the contaminated side.
A pressurisation system can be in use at all times for ventilation and ramped up during a fire condition, or it can
be dedicated for use during a fire only. The difference in pressure is only small and an overpressure of around
45-50 Pascal with doors closed, is recommended. This is greater than the pressure likely to be generated by the
Wiring to firefighters lifts
needs to be protected to
ensure personnel will not
become trapped in the
car.
https://www.gov.uk/gove
rnment/uploads/system/
uploads/attachment_data
/file/278168/FINAL_GRA_
3_2_Fighting_fires_in_hig
h_rise_buildings.pdf
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
fire itself, or by any adverse weather conditions, by a safety margin. The leakage path is a critical element of the
design process and there must be leakage from the clean area into adjoining areas, and ultimately to outside,
for the system to work satisfactorily.
Pressurisation in areas other than stairways or shafts, is also a useful system which can be controlled by FRS
personnel during a fire, to their advantage.
The diagram below shows how an office building can be pressurised to prevent the escape of smoke and fire
gases into the escape route during a fire, primarily to enable occupants to escape from the building. However,
this facility also allows conditions to be greatly improved for responding firefighters, cutting down on the
quantities of heat and smoke to be encountered and therefore speeding up efforts to locate the seat of the fire,
or to carry out any rescue operations, thus improving the safety and effectiveness of the response.
Diagram showing how a
pressurisation system uses
initial and final leakage
paths to vent air to
atmosphere
http://www.flaktwoods.com/
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
In the diagram above, options are available to vent the fire compartment through the use of smoke extraction,
but also to pressurise all areas around the fire compartment, to keep them smoke free for much longer and to
assist with evacuation and firefighting.
Building Management Systems (BMS)
The concept of a building management system is a fairly recent one and requires by FRS responders, to ensure
that all systems within a modern building are operating in a way that will not worsen the conditions experienced
during a fire.
A building management system (BMS), otherwise known as a building automation system (BAS), is a computer-
based control system installed in buildings that controls and monitors the building's mechanical and electrical
equipment such as ventilation, lighting, power systems, fire systems, and security systems.
(https://en.wikipedia.org/)
A BMS is generally found in larger, more complex buildings that make use of computerised controls to manage
HVAC (Heating, Ventilation and Air Conditioning) and associated electrical and gas systems. BMS in its simplest
form, manages the efficient usage of energy in the heating and ventilation of the building, through the use of
thermostats but the process can be far more complex than this, linked to ventilation and extraction or
pressurisation systems and also aligned with firefighting or fire control features of a building.
For example, by allowing the BMS to communicate with the fire detection and alarm system, it can be set up to
close all ducting systems down during a fire to prevent smoke spread, or to take control of all lifts and return
them to the ground floor, preventing their use except by firefighters.
Screen shot from a BMS http://www.airedale.com/
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Fire alarm systems and the FRS
Intelligent alarm and detection systems are known as analogue addressable types and they canbe of great use
to the responding FRS crews at a fire.
As they are equipped with computer technology, each detector head and all other components are linked to a
common system, but individually identifiable via a referencing process deploying unique ‘addresses’ fitted with
barcodes. In this way, the main alarm panel will indicate the nature of the alarm and show exactly the location,
number and type of detector(s) that have operated.
The alarm panel can be interrogated for further
details of the system and the event and can also be
used to provide a record of events during the
fire, for later analysis.
In complex buildings the alarm system can be
linked to a PA system so that essential messages can
be sent to occupants of one or more zones
within a building during a fire, instructing them to
evacuate, be on alert or remain where they are,
according to circumstances.
Alarms also allow the use of phased evacuation in
some buildings and this can again be over-ridden by
FRS personnel if necessary.
Central Control Room (CCR)
Any large complex will have a dedicated control room for security and management of critical events. Such a
control room will be fitted with the alarm panel and PA system described above, but is also likely to have CCTV
screens covering the building.
This can be a valuable source of information
during a fire, providing a picture of the venue and its
surroundings and helping to inform the incident
commander when formulating or updating the
operational plan.
The control room can also provide a suitable
location for team meetings of relevant managers and
inter-agency liaison.
Plans of the building and its systems are
potentially available in the control room, together
with files of the fire philosophy and contact
numbers for all relevant agencies, companies and
personnel.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Another feature managed through the control room is that of communication with all firefighting shafts and
disabled refuges.
Anyone waiting for assistance at a refuge can be seen by CCTV and spoken to by way of the communication
system linked to the CCR.
Fire Plans and keys
For many large or complex sites, fire plans will be held on site and made available to the FRS responding to an
incident. The fire plan, or fire pack is an essential item for helping FRS responders to find their way round a site
and for getting hold of potentially vital information, such as:
Access points
Assembly point
Water supplies
o Hydrants
o Open water sites
o Static tanks
Fixed installations
o Sprinkler stop valves
o Ventilation system controls
Services
o Electricity isolation
o Gas shut off valves
o Production shutdown
o Water stop cock
In addition, site plans will be necessary, to show the main features of buildings and identify some of the
main hazards that are on site, together with information about life risks or processes carried out.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Although local crews should be familiar with much of this information, it is always possible that responders
will be arriving from other areas and the first to arrive may not have any prior knowledge of the site and
how it operates.
This information is particularly important for complex fire engineered sites, where the operation of
technology-based systems can be used to advantage (or could cause a detriment if operated incorrectly).
It will also be useful to give contact details for all essential peronnel such as site engineers, production
managers, alarm company, control room, etc. Response times for personnel coming to the site from home,
during out of hours emergencies will sometimes be provided.
The fire pack will include
information about
assembly points for
occupants and emergency
access points for fire
service appliances
Site plans might be
needed, to show
zoning
arrangements for
access points or for
the fire detection
and alarm system.
This plan was
necessary during
the construction
phase only.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Keys and security
Along with the fire plans, there will sometimes be keys or a set of access codes to enable access into
relevant parts of a large or rescure site, if security personnel are not always available.
Other sites exist where security is a priority, such as prisons or defence establishments and there will be
strict protocols in place at premises such as these, to control access even during emergency incidents.
The same applies to sites where actions by responding FRS crews could put themselves and others in
danger, if they were not made aware of local rules and procedures. An example would be when responding
to an airport, either in support of local FRS responders, or to carry out firefighting duties in their own right.
Sensitive sites may need special access
arrangements, so responders might need
to be issued with a radio or escorted by
security staff to ensure their safety.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
When responding to an airside incident at an airport, crews will need to attend a pre-arranged rendez vous
point (RVP) and establish communication with either the control tower, or a designated person who will
appraise them of the actions needed. Normally, responding cres will be met by on-site personnel and
escported to the required location, where they may be reuired to provide water supplies, water relay or
manpower for fire and rescue operations.
An emergency responder file will often be given to the FRS incident commander, providing details of
common radio channels, access routes, hydrant supplies etc.
Specialist Risk Sites
When responding to hazardous sites in industry, such as refineries, chemical plant or tank farms, it is critical
to manage the response based on pre-arranged plans and information gathered during familairisation visits
carried out previously.
With this in mind, it is sometimes the case that specialist firefighting or PPE equipment has been stored at
key locations, for use by FRS responders during anemergency incident.
At a tank farm or refinery, for example, FRS pumps and foam monitors will be inadequate in the design and
capacities required for dealing with a large fire on a storage tank roof. Therefore, foam stocks and high
volume or long reach foam monitors may be available for use, together with plans of water supplies and
drainage systems etc.
Strict protocols are
enforced in airside areas
of an airport, to ensure
the safety of responding
personnel and the
continuing business
activity of aircraft and
other vehicles.
Tank farms found at oil storage depots or
refineries require specialist firefighting
equipment that may be available for FRS
use on site, working in tandem with site
operators.
http://www.gettyimages.co.uk/detail/video/aerial
-late-winter-afternoon-side-tracking-shot-of-
stock-video-footage/519068333
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Specialist bulk foam firefighting equipment, likely to be needed at a tank farm or refinery fire.
In some industrial sites, specialist PPE
must be available for firefighting where
the fuel involved presents special
hazards, to the extent that the local FRS
may not be equipped to send in its
personnel. Should PPE as this be made
available to local FRS firefighters, they
will need prior training and
familiarisation, to ensure safe operation.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Basement and underground areas- protective systems
Firefighting in basements and underground area such as car parks or generator spaces can be especially
hazardous and sometimes involves intense heat, as the heat from a fire is unable to escape to atmosphere.
In these locations, fixed firefighting or fire venting systems are often provided.
The type of fittings found can be as simple as a pavement vent light, used for centuries to allow built up heat
and smoke to vent from a basement. These can be hinged slabs built into the ground above a basement, or
they may simply incorporate sections of weak concrete that can be smashed into by firefighters, to allow
heat to vent out.
www.technocover.co.uk
Alternatively, basements can be fitted with fixed firefighting systems or foam distribution systems that rely
on FRS input of finished foam, to attack a fire around a generator or transformer, without having to commit
firefighters into the hazardous environment until the fire has been brought under some degree of control
and vented.
Traditional FRS foam inlet for a basement
In the above example, the inlet allows a foam making branch to be held against it by hand, the finished foam
pouring into the basement risk and helping to extinguish the fire from the outside.
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
Firefighting mains- wet and dry risers (or falling mains)
In very tall buildings, a wet riser is installed for fire fighting purposes. This is a pipe, permanently charged
with water to be immediately available on every floor, for firefighting. The hydrant outlets are known as
landing valves. If the pressure is insufficient, then booster pumps must be fitted and a tank supply may also
be needed, to supplement the pressure from the town main.
More usually, risers need to be charged from a pumped supply during the fire and these are called dry
risers.
Dry risers cut out the need for supplying a hose line up the stairway, or being hauled aloft from a FRS pump
outside. It has a much greater capacity than a line of hose and reduces the risk of burst hose in the supply
line. An air valve is fitted at the highest point, to allow air to vacate the pipe when it is charged with water.
Also, a drain valve at the lowest point will enable the system to be drained down after use.
Pipelines and emergency valves
A number of fuel pipelines cross the UK, carrying a range of hydrocarbon products ranging from aviation fuel to
natural gas. These pipelines are normally buried underground and encased in protective materials, the flow of
product being controlled remotely from a central control room.
Firefighting mains are fitted to many
buildings and can be dry or wet.
A dry riser requires water to be pumped
in to allow the system to be charged with
water at suitable pressure for firefighting
jets.
Pipeline location marker posts
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Fire Safety in the Built Environment FRS Facilities © Artemis TDL 2017
A network of pipelines crosses the country and one of the main users of this is the airport infrastructure,
where bulk supplies of fuel are constantly required. In an emergency event, access to manual control valves
may be needed and it can be down to the FRS to locate these based on prior knowledge and to send a crew
to shut down the supply valve, if this cannot be done remotely.
High pressures are often used, and the shut down has to be carried out in a controlled manner which is
likely to take some time.
https://infrastructure.planninginspectorate.gov.uk/wp-content/ipc/uploads/projects/TR040005/TR040005-
000751-130402_TR040005_National_Grid_Addendum_Appendix_8.PDF
Special risks- Tunnels
Tunnels exist under a number of our cities for a range of purposes. The anchor Exchange was built underneath
Birmingham in the 1950s as a secure location for essential telecommunications during the Cold War. It has now
been re-fitted to handle modern fibre-optic cable rather than the original copper telephone cables, but still
presents a risk for fire and rescue purposes.
Tunnels such as this should be provided
either with fire mains, or specific means
of accommodating fire hoses and
fittings.
Plans will need to be in place to prepare
for firefighting access and facilities
during an emergency.
http://www.birminghampost.co.uk/lifestyle/birmi
nghams-hidden-spaces-anchor-exchange-6449340
__MACOSX/._9. FRS Facilities- notes.pdf
Student Tasks 8 Fire Engineering.docx
1
Fire safety in the built environment Module 6FF011
Session 8 Fire Engineering
Group Tasks
Carry out research to explain, justify and illustrate your answers.
You need to investigate and report on some features of a fire engineered solution for a complex building.
You must describe the functional expectations and the role of the system you have chosen and explain how it operates and how it links in with other protective systems to support safe evacuation.
Detail the relevant quality standards or guidance (ie British / Euro standards; NFPA or FM) if applicable.
Task 1
Intelligent analogue addressable alarm system
The system has several hundred point detectors; beam detection; PAVA with recorded messages to support phased evacuation.
Task 2
Smoke and Heat Extraction and Ventilation System
Roof mounted extractor fans are used to exhaust fire gases, with the need for replacement air to be inlet at low level. The extraction system needs to be linked to other systems to ensure the correct areas are vented in a fire.
Task 3
Life safety sprinkler system
Sprinklers are fitted throughout the complex, including the external loading bays and underground car park for 1200 cars. External areas must be protected from frost.
Task 4
a. CCTV with fire recognition software.
b. Fire shutters and smoke curtains
CCTV is monitored in a central control room for security, but also supports fire detection.
When the alarm is triggered, smoke curtains and fire shutters operate in some areas to control smoke travel and dilution and to contain it within a single zone.
6FF011 Student Tasks 8 Fire Engineering
