Fire Alarm Systems for Sheltered and Extra Care Housing
There has been considerable confusion as to the appropriate fire warning strategy for sheltered and extra care housing. This has often resulted in a communal fire alarm system, similar to that installed in a hotel, in which, where a fire is detected by a fire detector within the flat or common parts, an alarm signal is given throughout the premises, including every flat. Such an arrangement contradicts the ‘stay put’ strategy adopted in sheltered housing, in which, when a fire is detected in one flat, there is no need for occupants of other flats to evacuate, nor need they do so in the event of detection of fire in the common parts. Not only does this cause confusion, but it is wholly unreasonable to expect residents to remain within their flat for any length of time while fire alarm sounders are operating within their flat.
Sheltered and extra care housing varies greatly in the design of the building, the nature of the residents, the level of support provided and the extent of communal facilities. Accordingly, it is not possible to specify a unique, generic form of fire detection and fire alarm system for all sheltered and extra care housing blocks. It is necessary for the specifier to consider the objectives of the fire warning and evacuation strategy, and to ensure that designs meet these objectives in specific circumstances. However, system design should be based on the principles outlined below, which follow the recommendations of BS 5839-6: 2013.
As in general needs housing, the ‘stay put’ strategy in sheltered and extra care housing is predicated on the assumption that the fire and rescue service will attend and extinguish any fire. It is also assumed that, if necessary, the fire and rescue service will instruct residents, in flats that might ultimately be affected by the fire, to evacuate.
In the case of sheltered and extra care housing, residents might be slower to evacuate if required to do so. Accordingly, there is a need to compensate for this by earlier attendance of the fire and rescue service.
On the basis of these considerations, the objectives of fire warning arrangements in sheltered and extra care housing are as follows:
a) to alert residents in the flat of fire origin to enable their early evacuation;
b) to result in the summoning of the fire and rescue service to the fire, so facilitating their early attendance (and, where relevant, action by staff), while avoiding, as far as practicable, attendance to false alarms; and
c) early detection of a fire in any communal facilities (such as lounges or laundries) that might grow to affect common escape routes; this permits a warning to be given within escape routes threatened by fire, ensuring that such areas are evacuated and not entered by residents.
The first of these objectives can be achieved, as in any housing, by the provision of interlinked domestic smoke and heat alarms within each flat; the smoke and heat alarms within one flat should not be interlinked with those in other flats. The extent of automatic fire detection in each flat should comply with the recommendations of BS 5839-6: 2013 for a Category LD1 system. Smoke alarms should be provided in all circulation spaces, and in all rooms, within each flat, other than kitchens, toilets, shower rooms and bathrooms. In kitchens, heat alarms should be provided. No fire detection need be provided in toilets, shower rooms and bathrooms or, normally, in cupboards. All smoke detectors within circulation spaces, or areas into which kitchens open, should be of the optical type; alternatively, appropriate multi-sensor detectors may be used.
It is acknowledged that this level of fire detection is not required for compliance with building regulations and may not be found within existing sheltered housing. However, this level of detection is strongly recommended for all new sheltered housing, upgrading of existing sheltered housing and when existing fire detection within flats is replaced. This standard should also be regarded as an ultimate objective for all existing sheltered housing.
Research has shown that low frequency alarm devices, such as those producing a 520 Hz square wave signal, are more effective in alerting persons who are hard of hearing in the event of fire; it is possible to connect devices producing this audible signal to some models of smoke alarm. Where residents are deaf or severely hard of hearing, additional fire warning devices, compliant with the requirements of BS 5446-3, should be provided to alert them in the event of fire. For residents who need to be warned when they are awake, visual alarm devices (flashing beacons) are normally suitable. If it is necessary to rouse deaf or severely hard of hearing people when they are asleep, vibrating pads, linked to the fire alarm system, should be used for this purpose; these are placed under pillows or mattresses.
The first objective (alerting residents to a fire in their own flat) could also be achieved by use of smoke and heat detectors connected to a communal fire detection and alarm system. If this arrangement is adopted, operation of the detector(s) within a flat should result in an audible alarm signal in that flat, but not in the common parts or any other flat.
The second objective, namely the early summoning of the fire and rescue service, is not primarily to effect a rescue of residents in the flat of fire origin; it is assumed that, generally, residents are capable of self-evacuation. If residents are not capable of self-evacuation, their safety in the event of fire cannot be assured by early warning and early summoning of the fire and rescue service alone.
The main reason for early summoning of the fire and rescue service is that, as in the case in any premises with a ‘stay put’ strategy, it may be necessary for the fire and rescue service to initiate evacuation of flats beyond the flat of fire origin, particularly if the fire proves difficult swiftly to bring under control. However, in premises within the scope of this guidance, it is recognised that response and evacuation by residents may take longer than in, for example, a general needs block of flats, and that residents may be more vulnerable to smoke within escape routes than the general population. The early attendance by the fire and rescue service provides some compensation for these factors. In addition, if the fire and rescue service are summoned immediately when a smoke detector operates, the potential for early extinguishment of the fire makes the need for the further evacuation of other flats less likely.
Notwithstanding the above, the changing demographics of the sheltered housing population are such that the need to rescue occupants in the flat of fire origin can be greater than in general needs housing. The likelihood of successful rescue is increased if fire and rescue service attendance times are short and there are measures to limit the development of fire prior to fire and rescue service attendance (e.g. a sprinkler or watermist system).
The early summoning of the fire and rescue service should be achieved by monitoring of the domestic smoke and heat alarms (or communal smoke and heat detectors) within each flat, so enabling fire alarm signals to be transmitted to any on-site scheme manager (or care staff in extra care housing) or, when no staff are available to respond to alarm signals, to an alarm receiving centre (ARC). In this case, alarm signals should be filtered by staff or the ARC (i.e. verifying the occurrence of a fire) to avoid summoning of the fire and rescue service to false alarms. While, in case of doubt, the fire and rescue service should always be summoned, effective filtering is necessary to avoid burdening the fire and rescue service with unwanted fire alarm signals. An effective way of achieving filtering is to use a social (“Telecare”) alarm system (which may already be necessary to monitor other devices, such as pull cord or pendant alarm devices), as this allows two-way speech communication with residents.
Certain engineering safeguards are necessary to ensure reliable alarm transmission by a social (“Telecare”) alarm system. In particular, it is necessary to ensure that a signal is transmitted, regardless of which smoke or heat detector operates. Fire signals need to be readily distinguishable from social alarm signals by staff and the ARC.
In addition, measures are necessary to ensure that receipt of alarm signals by staff, and by any ARC, is not significantly delayed if, prior to the fire alarm signal, a device on the social alarm signal is operated in the flat of fire origin or in any (or all) other flats. At the very least, under these circumstances, the display at the ARC ought immediately to indicate unambiguously a waiting fire alarm signal, without the need to interrupt speech communication initiated in response to a signal from a social alarm device.
Smoke (or heat) detection (as appropriate) should be installed in any communal facility, such as a communal lounge, laundry, etc., from where fire could spread to affect common escape routes; smoke detection should then also be installed within adjacent common escape routes. When a fire detector in any one of these areas operates, a signal should be transmitted to staff and/or an ARC, and sounders should operate throughout adjacent common parts to ensure that these areas are evacuated, while residents can still remain in their own flats.
Even if there are no communal facilities, where there might be combustible materials, such as chairs and tables, within common parts, smoke detection should also be installed within the common parts. Again, operation of these detectors should result in transmission of alarm signals to the scheme manager (or care staff) and/or ARC and trigger an audible alarm only in the common parts.
Where a communal system is installed because there are communal facilities and/or internal corridors containing combustible material, the system should be installed in accordance with the recommendations of BS 5839-6; manual call points should also be provided within the common parts. However, where there is a ‘stay put’ strategy, it is undesirable for the fire alarm signal in common parts to be audible within the flats; ideally, the sound pressure level within the flats should not exceed 45dB(A).
No communal system is necessary in simple sheltered housing that, architecturally, is similar to a general needs block of flats with no communal facilities; fire detection can be limited to the remotely monitored smoke and heat alarms in each flat. However, smoke detection (but not manual call points) might be necessary to operate automatically opening vents (see paragraphs 79.6-79.9). In this case, the smoke detection should generally be installed in accordance with the recommendations of BS 5839-1, except that no sounders should be provided.
No fire detection need be installed within roof voids, provided the compartmentation within roof voids satisfies the recommendations of this guide (see paragraphs 76.4-76.6) and there are no significant fire hazards (e.g. boilers, photovoltaic systems, etc.) within the voids. Where, as a result of such hazards, fire detection within the voids is considered to be necessary, the type of detection and its fire warning strategy will depend on the location of the fire hazards. If the hazards exist in the void above a flat, the detection may comprise smoke alarms linked only to the smoke alarms in the flat. If the fire hazards exist within a void over common parts, the fire detection should give a warning in the common parts.
If a communal system is installed, as a further enhancement, heat detectors, connected to this system, could be installed within the hallway of each flat (in addition to the smoke alarm(s) within the flat). The heat detectors could be used as confirmation of a fire within a flat. However, the provision of the heat detectors does not obviate the need for remote monitoring of the domestic smoke alarms (or communal system smoke detectors) in each flat, as heat detectors would not result in early enough summoning of the fire and rescue service. Under these circumstances, if a heat detector operates, it might be appropriate, according to the fire risk assessment for the premises, to evacuate adjacent (or all) common parts and, if appropriate, where staff are present on a 24-hour basis, certain flats in close proximity to the flat of fire origin.
Any ARC to which fire alarm signals from a communal fire detection and fire alarm system in sheltered housing are transmitted may be, but need not necessarily be, the same ARC to which fire alarm signals from flats are relayed, as filtering by two-way speech communication is not normally possible for fire alarm signals within common parts or communal facilities.
To satisfy the recommendations of BS 5839-6, the standby batteries for a Grade A system should be able to operate the system for 72 hours in the event of mains failure, after which there should be sufficient capacity to sound an evacuation signal for 15 minutes. However, in premises with at least one member of staff present (whether awake or asleep) on a 24-hour basis, or where a mains fault on the fire alarm system is automatically transmitted to an ARC that will arrange for appropriate action to be taken, the period of 72 hours may be reduced to 24 hours.