Two false fire alarms activations call out the London Fire at Gym

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Fire alarm company Fire Systems Ltd, look into a typical false alarm incident at a Gym in North London.

Full fire brigade emergency responses were recently triggered when false fire alarm activations prompted crews from Hornsey fire station to turn up twice at a London gym last week.

Staff and Gym members in swimsuits and leotards were forced to evacuate onto the street assembly point when the two fire alarms at Virgin Active in Topsfield Parade, Crouch End, were triggered on Thursday and Friday (July 22nd and 23rd).

A gym staff member stated that the first false fire alarm activation was raised after someone rightly thought they spotted smoke. This sighting proved to be correct but it was not a real fire.

However, a fire brigade spokesman said such incidents are common in London and explained: "If you see smoke it's quite common that it's the boiler or condensation steam coming out. It happens quite a lot with gyms."

This highlights the importance of reducing false alarms and unwanted fire signals by providing adequate staff fire training and making sure that any fire incident is managed in a professional matter, as it can minimise call outs for fire and rescue services, thereby saving money, time and resources that may be required elsewhere.

Having your fire alarm system service and maintained by a professional fire alarm company such as Fire System Ltd, can reduce false alarms, minimising cost and company downtime through false alarms..

Fire alarm protection of property

If you are a fire alarm installer and the objective for the fire alarm system is property protection, there needs to be sufficient provision of wired or wireless fire alarm automatic fire detection to ensure that fire is detected at an early stage, that an effective warning is given in time for fire-fighters to take action before unacceptable damage to property occurs and that an indication of the location of the fire is given to those responding to the fire alarm signal. The value of the fire system will depend on a combination of the speed of detection, the delay before fire-fighters are summoned, the attendance time of trained fire-fighters,
and the probable rate of fire spread. If the attendance time of the fire service (whether private or local
authority) is incompatible with the probable rate of fire spread, adequate property protection might not be
achieved purely by automatic fire detection, even if a Category P1 system is installed. The system may,
however, form one component of a “package” of fire protection measures, such as compartmentation (to limit
the extent of fire spread prior to the arrival of the fire service) or an automatic fire suppression system (to control or extinguish the fire prior to the arrival of the fire service).

Fire Systems Ltd a company based fire alarm installer in Kingston Upon Thames, specialise in fire alarm installation, especially in the field of wireless fire alarm equipment.

Fire Alarm false alarms

A guide and advice on reducing false alarms in premises is now being considered by Fire Systems Ltd. The guide will incorporate both wired and wireless fire alarm systems.

The ‘white paper’, Reducing Unwanted Fire alarm Signals within premises will be designed to help fire safety managers and others involved in fire alarm management and fire safety. It will offer advice on integrating the management of unwanted fire signals into fire risk assessments, guidance on relevant good practice and standards, and a section on fire alarm maintenance to help reduce false alarms.

The document will also include an update on potentially suitable wireless fire alarm systems and technologies, some of which are available from Fire Systems Ltd.

"In business properties and particularly large buildings, unwanted fire signals can cause huge disruption to the day-to-day running of the facility," said Will Mason, fire product marketing manager at Fire Systems Ltd. "The aim of the new whitepaper is to help ensure those responsible for building facilities have as much guidance and information as possible at their disposal to be able to provide a safer environment."

We are finding the sudden increase in the supply and installation of wireless fire alarm systems are enabling us to liaise well in advance with the clients and advise all parties of reducing false alarms.

Highest category fire alarm design L1

When designing fire alarm systems, the highest possible enhancement of life safety is provided by a Category L1 system. In a Category L1 fire system, all areas of the building are protected by automatic fire detection. In rooms or areas in which there
is a need for automatic fire detection of fire in order to protect the occupants of these rooms or areas, smoke or combustion gas detectors need to be provided. In other rooms, heat detectors might be acceptable.

An L1 fire alarm system might be appropriate in buildings in which there is a significant number of occupants at special risk
in the event of fire (e.g. hospitals and certain residential care premises), or in which, throughout the building, structural fire precautions are not of as high a standard as normally specified for buildings of that type.
A Category M fire alarm system, in which there is no automatic fire detection system, is only likely to suffice if no one
sleeps in the building and fire is likely to be detected by people before smoke seriously reduces visibility in the escape routes.

Fire Alarm system design

Fire alarm design has to consider the category of the purposed system. The design principles are the same whether you are installing a wireless fire alarm or a wired one. In some circumstances, even a Category L3 fire system might not be sufficient to achieve the life safety objective.
A fire risk assessment might determine that, in addition to the protection afforded by a Category L3 system,
fire detectors need to be installed in rooms or areas that would not be protected in a Category L3 fire alarm system. The
resulting system would then be a Category L2 system. A Category L2 system would be appropriate if a risk assessment determines that the fire risk associated with rooms other than those opening onto escape routes is unacceptable. Alternatively, there might be a need to give enhanced early warning to occupants of certain
rooms, such as disabled people, of a fire in their own room. In this case, wired smoke detection or wireless fire alarm detectors
within the rooms in question are necessary; heat detectors will not respond quickly enough.

(17 end)

Fire Alarm design, protection of life

(17) In some buildings, a fire risk assessment might determine that an unacceptable risk to occupants can be reduced by the installation of a fire alarm or a wireless fire alarm, with fire detectors in only selected rooms or areas in the building. A Category L5  fire system might then be suitable, A Category L5 fire system may form part of a fire engineering
solution, in which automatic fire detection is just one component of the solution.
if after conducting a fire risk assessment, there is a need for a reliable means of warning of the presence of smoke in escape routes, a Category L4 designed fire alarm system, in which smoke detectors are installed in escape routes, such as corridors and stairways, may be appropriate. For example, this can arise from the presence of lone workers in a large, generally unoccupied area of a building in which the fire hazard level is assessed to be relatively high.

In buildings that are listed or it is difficult to install wiring, a wireless fire alarm should be considered. In buildings in which people sleep within rooms accessed by corridors, other than short lengths of corridor, research has shown that passage of hot fire gases through a door crack can produce smoke sufficiently dense
and cool for a corridor to become smoke-logged before adequate warning can be given by detectors in the corridor. In this case, a Category L3 fire alarm system, in which detectors are installed in rooms that open onto the escape routes, as well as within the escape routes themselves, is likely to be appropriate. Nowadays, this decision is taking after a fire risk assessment has been carried out to identify the possible risk from fire. The purpose of the
detectors in these rooms is to give an early enough warning to occupants, other than, possibly, the person in the room of fire origin, such that they have adequate time to escape before their escape route is impassable as a result of smoke. Accordingly, within the rooms, the use of one or more of the following types of detectors
is satisfactory: heat, smoke, or wireless fire alarm detection.

fire alarm design considerations

(17) Before a fundamental fire alarm system design can begin, whether it be a wireless fire alarm system or a wired system, it is essential that the category is defined, as this will decide on the areas in which the fire alarm detection are to be installed, along with the other design parameters of the system. The areas that are to be protected by the fire alarm system need to be such at to meet the design objective.

NOTE: Fire System Category is simply a shorthand means of describing whether the fire alarm system is manual or automatic, and in the case of automatic systems, the object of the automatic fire detection system. The appropriate extent of automatic fire detection will normally be determined by a fire risk assessment, rather than a rigid application of system Category to every building of a specific type or occupancy.

If the objective is to protect the occupants of a building in which no one sleeps, and fire is likely to be detected by people before smoke seriously reduces visibility in escape routes, an automatic wireless fire alarm or wired alarm might not be necessary: a Category M system might suffice. Whether there is a need for automatic fire detection and, if so,
the extent to which it needs to be provided, will often be determined by a fire risk assessment carried out on behalf of the user; such a fire risk assessment might be required by legislation, such as the fire safety order.

If there is significant probability that a fire in the building, or part of the building, could threaten escape by occupants before it is detected by people in the building, a Category M system is unlikely to be adequate, and the provision of automatic wireless fire alarm or a wired system will be necessary. This could arise from the likelihood of the presence
of occupants at special risk (including sleeping occupants), inadequate structural fire protection or the probability of very rapid fire development.

Fire alarm variation continued

(14) To continue with our last blog regarding fire alarm variations when designing fire alarms to BS5839.

Thus, for example, although this BS5839. standard recommends that no one should travel further than 45 m to reach
the nearest fire system manual call point, a competent person might judge that, in a particular building, a distance of 47 m is acceptable because, perhaps, this leads to the most appropriate locations for the manual call points. Similarly, in an office building, it might be judged that, say, sound pressure levels of 57 dB(A) could be acceptable in a number of outer small offices, since to achieve the 60 dB(A) as recommended in this standard, the cost to achieve the additional three decibels would not justify the cost.

Recommendations:

1) Any variations from the recommendations of the fire alarm design code part of BS 5839 incorporated within a specification
or design proposal should be clearly identified, so that they are obvious to any party from whom approval of the specification or design proposal may be sought, such as the user, purchaser, enforcing authority or insurer.
2) Any variations from the recommendations of the fire alarm design code part of BS 5839identified or proposed during
installation or commissioning, but not clearly identified in the documented design, should be documented
(other than in the case of errors or “snags” for which rectification is proposed), for subsequent approval.

Variation against the fire alarm code BS5839

When designing fire alarm systems, there are occasions, when the fire alarm designer will deviate away from the standard. The recommendations are primarily based on recognized good practice in the design,  installation, commissioning and maintenance of fire detection and fire alarm system. Accordingly, they are
likely to be suitable for the majority of normal applications.
There will, however, be applications in which the recommendations are unsuitable and would lead to fire alarm systems that would be unnecessarily expensive, incorporating measures that could not be regarded as  cost-effective, or that could be difficult to install. In extreme cases, the recommendations might even be
inadequate to provide the appropriate level of protection.
In these circumstances, variations from the recommendations may be necessary, even though, in general, the user, purchaser, enforcing authority or insurer requires quite strict compliance with the standard.
Variations were described as “deviations” in the previous version of this part of BS 5839. This term is now
deprecated, since it implied shortcomings or errors in design, whereas, in reality, the term referred to aspects
of design that were appropriate and intentional, albeit not compliant with one or more recommendations of
the standard.
This does not, however, imply that the designer or installer has freedom to ignore the recommendations of
this standard under circumstances in which a user, purchaser, enforcing authority or insurer seeks
compliance with it. Variations always need to be the subject of specific agreement amongst all interested
parties and need to be clearly identified in all relevant fire alarm system documentation.
Some variations can arise from a fire risk assessment, in which it is determined, for example, that an area of the building may be unprotected by automatic fire alarm system, albeit that, in the Category of fire alarm  otherwise deemed necessary, protection is recommended in this standard. Other variations may be based on
the engineering judgement of a competent person, who might, for example, consider that the extent of protection disabled in the event of a single cable fault can slightly exceed the limitations recommended in  this standard, without any significant decrease in the integrity of the fire alarm.
It also needs to be borne in mind that, while it is necessary for certain limitations or performance levels  recommended in this standard to be quantified, so that the relevant recommendations are expressed
numerically, the values quoted are often arbitrary. The values are often based on well-established and
proven custom and practice, or on the judgement of experts. While they are, therefore, generally applicable,
rigid adherence to them might not be appropriate in every case, nor is it the case that minor variations need necessarily have any significant effect. Any deviations away from the standards should be after a fire risk assessment has been conducted.

fire alarm interfacing with other services

Where a fire detection and fire alarm system, whether it be wired or a wireless fire alarm system, is to be integrated with a voice alarm system, one organization such as the fire alarm company (Fire Systems ltd), should take responsibility for the interface connections and all necessary communications
between the fire detection and alarm system and the voice alarm system.

When the fire alarm installer an wireless fire alarm system, this would be in the form of wireless output units, or if a wired system it would be addressable output unit on the loop detection circuits.

Where a fire detection and fire alarm system is to be interfaced with another system or facility (such as a fire suppression system, smoke control system or lift grounding facility) that is the responsibility of an
fire alarm company, or another organisation, other than the fire alarm installer of the fire detection and alarm system, the responsibility of each organization should be clearly defined and documented.

The purpose of a fire alarm

The purpose of a fire alarm system, whether it be wired or a wireless fire alarm system, is to support the fire safety strategy for the building. It is, in particular, important that system design suitably supports the required fire evacuation procedures, rather than those
procedures being designed around a pre-determined system design. A fire risk assessment of how the building is to be used is advisable at this stage.

To a large extent, the design of the fire alarm system will depend on the actions and procedures required after the fire alarm has been given. Particular care is necessary in the case of a fire system that is to be capable of giving a two (or more) stage alarm.
If a premises contains fire systems associated with hazards other than fire, the various hazard alarms need to be properly co-ordinated and be distinct from each other. In these types of buildings, the relative priorities need to be carefully assessed, and the system arranged so that a higher priority alarm cannot be prevented
or obscured by one of a lower priority. Although, in general, fire will have the highest priority, there are buildings in which other hazards can have higher priorities than fire.

The system requirements, including those imposed by the evacuation procedures, the configuration of the building, and the use to which the building is put, need to be ascertained as accurately as possible by
consultation between the user or purchaser and other interested parties, such as the fire risk assessment person, enforcing authority or fire insurer.
It is advisable that there also be relevant consultation between the user or purchaser and the fire system designer. In a small, simple building, the extent to which such consultation is necessary may be minimal;
the user or purchaser might have little knowledge of fire safety principles, and system design can involve
little more than determination of the appropriate locations of manual call points and fire alarm devices. In
complex premises, there will be a need for extensive consultation between the user or purchaser, the enforcing
authority, the system designer and, possibly, specialist consultants.

Fire alarm system categories

Fire alarm systems may be installed in buildings or premises to satisfy one, or both, of two principal objectives, namely
protection of life and protection of property. The objectives of a fire alarm may differ in time or place. Other possible
objectives exist, such as protection against business interruption that can be caused by false alarms and protection of the environment; these are likely to be satisfied by the recommendations in this standard for protection of property.

Fire alarm systems that are protecting property are different as the sound level requirement is not as critical, the fire alarm would usually be connected to the fire brigade and there may be additional fire detection as the building needs to be able to call the fire brigade when the building is not occupied. A fire alarm that is designed to protect property is under the “P” category of design fire alarm system.

Categories of fire alarm

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 aware of the fire, and able to raise the alarm by use of a manual call point, before it is detected automatically.

If a fire alarm/wireless fire alarm is intended to fulfil the objectives of more than one Category of system, then the system needs to
comply with the recommendations for each of the Categories. For example, a fire alarm system whose sole purpose is to provide property protection throughout the building (a Category P1 fire system) might not need to give an alarm signal of sufficient audibility to rouse all occupants who might sleep in the building. If, however, the system
were also installed for the purpose of life safety (a Category L system), sufficient fire alarm sounders to rouse sleeping occupants would be necessary.

This part of BS 5839 does not recommend which Category of system needs to be installed in any given premises. The various system Categories need to be regarded as a “menu”, from which purchasers, users, specifiers, enforcing authorities, insurers or system designers may select a suitable system for any building. A fire risk assessment is advisable as this gives an assessment of the fire risk as to how the building is used and in operation.

Because of the wide range of fire alarm systems, including wireless fire alarm systems, covered by the recommendations of part of BS 5839, the specification of requirements for a system, by a purchaser, user, enforcing authority or insurer or fire risk assessment personnel, or the description of a system by a designer or installer, by reference to this standard, without a reference to system Category, will have little meaning. The Category of system to be installed always needs to be included in the specification. Similarly, the
specification of any Category of system, other than Category L1 or P1, always needs to include details of
those areas of the building that are to be protected.

Fire Alarm design

Automatic fire detection on wireless fire alarms or wired fire alarm systems, is also commonly used to protect buildings by ensuring the early attendance of the fire brigade, as a result of the summoning of the brigade by occupants of the building or by transmission of fire alarm signals to an alarm receiving centre from where the fire brigade service will be called. Automatic fire detection systems might, therefore, be required or recommended by the property insurers or after a fire risk assessment.

When designing a wireless fire alarm or a wired system,the early detection of fire by automatic means, and rapid summoning of the fire service, is also important in premises in which staff, residents, people with a disability cannot readily be evacuated immediately in the event of fire (e.g. hospitals).

Manual fire alarm systems are often sufficient to satisfy legislation in workplaces in which no one sleeps, but once again a fire risk assessment would be required to assess the risk.

Wireless fire alarms or wired automatic fire detection is usually required by legislation to supplement the manual system in premises in which people sleep. Automatic fire detection might also be necessary to satisfy legislation under the following
circumstances:
a) where the automatic fire detection forms part of a fire engineering solution;
b) where fire protection systems, such as door closing facilities or smoke control systems, are to be operated
automatically in the event of fire;
c) where the low level of occupancy of a building, or part of a building, is such as to create the potential
for fire to prejudice means of escape by occupants before they are aware of the fire.

The Need for a Fire Alarm System

The requirement for a fire alarm system in any specific type of  building will usually be decided by the authority
responsible for enforcing fire safety legislation in that building and/or by a fire risk assessment carried out by the owner, landlord, occupier(s) or employer(s), as appropriate.

Usually, it is appropriate to install some form of fire alarm system or wireless fire alarm with fire detection in virtually all buildings , other than very small premises that are relatively open-planned so that any fire will be quickly detected by occupants, who will be able to warn others by word
of mouth or simple mechanical devices such as hand-operated bells.

However, even in open planned office environments, it would be wise to have a manual operating fire alarm system, locating a manual call point at all exits leaving the building. Once again, the manual system could be a wireless fire alarm with manual call points saving labour time if the area to be covered is large. This option could be considered after carrying out a fire risk assessment as required by the fire safety order 2005.

Fire Alarm communication with the fire service

For a fire alarm system to give the maximum benefit, the fire service needs to be called as quickly as possible on every occasion that it operates, unless, in order to avoid false alarms being passed to the fire service, the fire alarm has filtering arrangements, such as delayed timer output or coincidence signalling are appropriate
In occupied buildings, the primary means for calling the fire service needs to comprise a call to the fire brigade by occupants, using the 999 (or 112) public emergency call system. This is the case even if there is a means for automatic transmission of fire alarms to an alarm receiving centre, as any automatic system can fail at the time it is required to operate. It needs to be ensured that the fire alarm sounders cannot interfere with any emergency call to the fire service.

In the case of manual fire alarm systems, automatic transmission to an alarm receiving centre is usually unnecessary. When the building is unoccupied, the system will not respond to fire; when the building is
occupied, the call to the brigade from occupants will suffice. However, this would be decided after a fire risk assessment is conducted.

Fire alarms with an automatic means for transmission is only likely to be of benefit, as a secondary means of summoning the fire brigade, if factors such as the size or complexity of the building, or low level of occupancy, could result in a significant delay between discovery of fire and
summoning of the brigade, thereby warranting the duplication of the call to the fire service (i.e. with calls
made manually from the premises and automatically via an alarm receiving centre).

Since the objective of a Category L system is evacuation of occupants, rather than protection of property,
manual summoning of the fire service by occupants may, again, suffice, but again a fire risk assessment should be conducted to assist in making such decisions. However, if the early attendance of the fire brigade is likely to be essential to life safety in the event of fire (e.g. in hospitals), a secondary, automatic means of transmission might be warranted, unless there are adequate arrangements to ensure that there will be no delay at any time in manual summoning of the fire service by occupants.

Manual Fire Alarm systems

I attended a fire risk assessment course recently and during a discussion with the tutor regarding fire alarm automatic detection , he explained that automatic detection is not required in a office type building environment as the people detect fires quicker then fire detection. However, I disagree, as humans will not always be in the place where a fire may start. The point of fire alarm automatic detection is to give the staff the earliest form of warning that a fire has started. What is the point of the L standards within BS5839, if not to guide the fire alarm designer of the locations of the fire detection required?

Having a manual fire alarm system in a open environment is practical as the visual ability to see all the area assist in located the fire and enabling staff to activate the fire alarm.

However, all of the above, is to be decided after a fire risk assessment is conducted by a competent person.

Fire alarm design - Sounders

Fire Alarm sounders are a critical part of any fire alarm system. Most modern systems whether it be a wired or wireless fire alarm usually will have electronic sounders. The bell sounders are usually found on the older type of system.

The minimum sounder level on a fire alarm protecting a commercial building is 65 decibels, or 60 decibels for the outer rooms. However, sleeping areas require 75 decibels at the bed head.

Wireless fire alarm sounders have now started incorporating the base sounder along with wired systems, but the cost for the wireless fire alarm sounders can be quite expensive.

Fire alarm battery calculation to be considered

When designing a wired fire alarm system or a wireless fire alarm system, battery calculation must be considered.

BS5839-1 recommends in the event of a power failure, the fire alarm system should be able to operate as normal for 24 hours, and then have enough power to operate the sounders for 30 minutes.

To be able to allowed for this within the fire alarm design, the current load information would be required for all of the fire alarm equipment you are proposing to use.

There is usually less of a concern when dealing with a wireless fire alarm system, as all the external fire detection have their own internal batteries. But the devices within the a wireless fire alarm system, will usually have an A and B, back up supply.

Fire Alarm Recommendations British Standards

The following fire alarm recommendations are applicable.

a) Where there is uncertainty regarding the need for a fire alarm system, or the Category of fire alarm that should be used reference should be made, by the designer, developer, potential purchaser or user, to
one or more of the following:
1) relevant part of BS 5588;
2) guidance documents that support fire safety legislation;
3) any authority responsible for enforcing fire safety legislation that applies to the premises;
4) the property insurer;
5) any relevant fire risk assessment.

b) The purchaser or user should ensure that the designer of a fire detection and fire alarm system is adequately appraised of the objectives of the system and any relevant requirements of enforcing
authorities and insurers.

Wireless fire alarm ideal if Asbestos is around

When having to install a fire alarm system in a environment where it has been confirm that Asbestos is present, trying to install a wired fire alarm system is very costly due to all the safety measures that have to be taken.

Fire Systems Ltd, have come across this situation on numerous occasions and have opted for their state of the art wireless fire alarm system. With the need for limited wiring, the installation aspect of the fire alarm installation is greatly reduced for the fire alarm installer.

The fire detection is easily installed with minimum disruption to the building fabric.

For more information, contact Fire Systems on www.firesystems.co.uk

Radio Fire alarms or Wireless fire alarms ?

What name is the common name used for non wire fire alarm systems? Is it Radio fire alarm or wireless fire alarm? It would appear that the popular choice is wireless fire alarm systems.

The largest manufacturer of wireless fire alarm is EMS, who for many years only had one serious competitor a fire systems manufacturer by the name of EDA. However, times are changing and there are now a few more players within the Radio fire alarm or wireless fire alarm market. Such a Hyfire, detectomat and now fulleon.

We at Fire Systems Ltd, are finding that the Hyfire Hybrid wireless fire alarm system is our best seller. And when promoting our wireless range we rarely use the term Radio fire alarm.

Fulleon, as mentioned previously are now in the Radio fire alarm market, but it would appear had difficulty bringing their product to market.

Wireless fire alarm upgrade Clarendon Hotel

Following on from my last blog, why did the hotel opt for a wireless fire alarm system and why chose Fire Systems Ltd?

The Hotel currently has a very old conventional fire alarm system. The fire detection was well over 10 years old, and had approximately 12 zones in use. As you can imagine the seek and search time if the fire alarm activated was unacceptable for the paying guest, as the staff would only known the zone area of the activated fire detection device, not the exact location.There is currently no time delay on the existing fire alarm system, therefore the staff would have to either evacuate the hotel straightway, or silence the bells and then investigate the fire alarm activation, not always a wise thing to do?

With the proposed new addressable wireless fire alarm system, in the event of a fire alarm activation, the location of the smoke alarm or manual call point device is registered on the fire alarm panel display.

The hotel chose Fire Systems Ltd, because of our reputation when it comes to wireless fire alarm designing and installation, and our design was well thought-out and cost effective.

I will answer why the hotel opted for a wireless fire alarm in the next blog.

Fire Systems Ltd begins wireless fire alarm upgrade at the Clarendon Hotel.

Fire Systems Ltd, has commence the upgrade of the existing conventional fire alarm system to a Hyfire Hybrid wireless fire alarm system.

Fire Systems Ltd, are well known for the specialist skills when it comes to designing and installing wireless fire alarm systems.

The first stage of this project will involve tracing out all the existing sounder circuits and converting them to addressable fire alarm detection. Close liaising with the hotel is important to ensure the first stage goes well. Tracing of the sounders circuits will involve ringing the sounders sometimes to verify the direction of the circuit if using the multimeter proves difficult.

On completion of tracing out the circuits a detailed calculation will be required to ascertain if all the equipment proposed on the circuit does not exceed the fire alarm manufactures current load per loop.

Fire detection when designing fire alarms

When designing fire alarms and considering fire detection, fire detectors are designed to detect one or more of the four characteristics of fire, namely:
— heat;
— smoke;
— combustion gas (such as carbon monoxide);
— infra-red or ultraviolet radiation.
In some fire detection systems, a fire alarm signal is initiated when the characteristic reaches a pre-determined
threshold. A fire alarm signal may, instead or in addition, be initiated when the rate-of-change of the characteristic is representative of a fire.

In the case of fire systems with smoke or heat detectors, the characteristic is detected at a defined point(s) within the protected area. In contrast “line” detectors are capable of detecting the characteristic along a defined line within the protected space. In a fire alarm “integrating line detector”, the effect of the characteristic on the detector is integrated along the
line. In a “non-integrating line detector”, this is not the case, and the detector behaves, effectively, as though
it comprised an infinite number of point detectors arranged along a line.
In multi-sensor fire detectors, each detector contains more than one sensor and thus monitors more than one
of the characteristic fire phenomena (e.g. heat and smoke). By analysis of the signals received from the
smoke alarm sensors, potential response to phenomena other than fire can be reduced while still providing an adequate
response to fire.

Fire alarm design

When designing fire alarm systems whether be wireless fire alarms, addressable fire alarms or conventional systems, in accordance with fire code BS5839-1, fire detection in the form of fire detectors should be mounted at least 500mm away from walls or ceiling obstructions greater than 250mm deep and at least twice the depth of obstructions less than 250mm deep.

The detectors should also be mounted at least 1m away from any forced air inlet. Where the obstruction is greater than 10% of the height of an area it should be considered as a wall. Similarly a floor mounted obstruction (such as racking) should be considered a wall if it
comes to within 300mm of the height of the detector.

When designing fire alarm system where fire detection is required in vertical shafts, such as stairwells, a smoke detector should be mounted at the top of the shaft and within 1.5m at each level.

However, when designing wireless fire alarm systems, the fire code now used is EN54.

The need for a fire alarm

The need for a fire alarm system in a particular building will normally be determined by the fire authorities responsible for enforcing fire safety legislation in that building and/or by a fire risk assessment carried out by the owner, landlord, occupier(s) or employer(s), as appropriate. In general, it is appropriate to install some form of fire alarm system in virtually all buildings, other than very small premises that are relatively open-planned so that any fire will be quickly detected by occupants, who will be able to warn others by word of mouth or simple mechanical devices such as hand-operated bells.

Manual fire alarm systems are often sufficient to satisfy legislation in workplaces in which no one sleeps.
Automatic fire detection is usually required by legislation to supplement a manual fire alarm system in premises in
which people sleep. An Automatic fire alarm with fire detection might also be necessary to satisfy legislation under the following
circumstances:

a) where the automatic fire detection forms part of a fire engineering solution;
b) where fire protection systems, such as door closing facilities or smoke control systems, are to be operated
automatically in the event of fire;
c) where the low level of occupancy of a building, or part of a building, is such as to create the potential
for fire to prejudice means of escape by occupants before they are aware of the fire.

Wireless Fire alarm manual call point

The following recommendations are applicable when designing fire alarm systems in accordance with BS5839-1.

If a fire alarm manual call points are located on the landings of an enclosed stairway the fire alarm manual call point on each level, other than a final exit level from the stairway, should be incorporated within the zone that serves the adjacent accommodation on that level.

A fire alarm manual call point located within the stairwell at a final exit to open air may be incorporated within the fire detection zone serving the stairwell.

When designing a fire alarm system, If the total floor area of the building is greater than 300 m2, each fire detection zone should be restricted to a single storey.
If the total floor area of the building is less than 300 m2 a fire detection zone may cover more than a single storey.

For voids above or below the floor area of a room, these may be included within the same fire zone of the room, provided that the voids and the room constitute a single fire compartment.

Categories of fire alarms – Part 6 Residential

Fire detection and fire alarm systems are usually installed in dwellings to protect life. However, the level of fire protection afforded to occupants needs to be related to the fire risk involved. The appropriate level of protection required can therefore vary considerably. For the purposes of this standard BS5839-6, fire systems are classified as follows, according to the level of fire protection that they afford.

Category LD: a fire detection and fire alarm system intended for the protection of life.
NOTE 1: The designation “LD” is used to distinguish these fire alarm systems, which are intended only for dwellings, from Category L systems  as defined in BS 5839-1, which are intended for the protection of life in any type of building.

Category LD systems are subdivided into:

Category LD1: a fire system installed throughout the dwelling, incorporating smoke detectors in all circulation spaces that form part of the escape routes from the dwelling, and in all rooms and areas in which fire might start, other than toilets, bathrooms and
shower rooms;

Category LD2: a system incorporating smoke or heat detectors in all circulation spaces that form part of the escape routes from the dwelling, and in all rooms or areas that present a high fire
risk to occupants .

Category LD3: a system incorporating smoke detectors in all circulation spaces that form part of the escape routes from the dwelling.

Legislation is being proposed making it a legal requirement for smoke detection to be fitted...

 

Proposed legislation making it a legal requirement for smoke detection in the form of smoke alarms are to be fitted in rented properties has been introduced in Parliament by Torbay MP Adrian Sanders.

The Bill given the name “The Fire Safety (Protection of Tenants)” was given its formal first reading in the Commons yesterday, following the weekly Prime Minister's Questions.

Five people a week die from a domestic house fire with no fire detection, whether it be a fire alarm system or a smoke alarm, and the Lib Dem MP has branded it unacceptable.

 

 

It follows the deaths of two youngsters from Torquay Stephanie Wojak and Ben McAuliffe in the Ellacombe blaze in October.

There was no fire alarm in the house in Ellacombe Church Road where the children lived with Gill and Mike Wojak and their son Ricky.

25 per cent of the trust’s homes do not have a fire alarm, which equates to some 690 properties.

It had planned to install fire detection in the remaining properties as part of a major home improvement programme, which it brought forward immediately.

Mr Sanders wants to ensure that there are working fire alarm safety devices in all rented properties at the start of a tenancy.

Fire alarm or smoke alarm essential

Family escape a fire that broke out in the kitchen.

Thick black smoke filled the kitchen in their house in Perth Road, Plains farm after a fire broke out from an electrical fault.

The advice to be given hear is to ensure your fire detection i.e smoke alarms have mains and battery back up. Fire Alarms, have a fire alarm control panel that will be fed by 240v mains supply, but will also have a battery back up. This is important because as in the instance stated above, the short circuit cause the fire and shorted out the mains supply. if you fire detection is fed by mains only, the smoke detector will not operate to alert you of fire.

Wireless fire alarms fire detection, has only battery for its supply, so will not have any a problem with the situation as stated above.

Fire systems Ltd, can assist you with all you fire alarm needs. visit our website on www.firesystems.co.uk.

Lucky fire escape – Smoke Alarms is important

Thanks to an early dog walker, a family living in Blackrod, had a lucky escape from a fire at their home.

The fire is believed to have started in a metal outhouse attached to the house. The smoke and flames had already spread to cause damage to the rear door of the house and had caused the upstairs bedroom window to crack, where the couples young four year old daughter was asleep.

The house was not fitted with any fire alarm or fire detection equipment such as working smoke alarms and had it not been for the passerby alerting the family to the danger, the outcome could have been disastrous .

Do not leave your fire safety to the chance of a passing dog walker, install a fire alarm system, or smoke alarms according to the risk involved. You can contact Fire Systems Ltd for advice. Fire Systems Ltd, specialise in wireless fire alarms, and are an independent fire alarm company.