FIA Technical Manager Phil Martin looks at some of the more significant changes introduced in the new standards and some of the reasons behind them.
Part One
BS 5839-1:2002 was updated with amendment A1 in 2004 and then amendment A2 in 2008. The industry was anticipating that there would be a further amendment in 2013, therefore many were surprised when it was released as BS 5839-1:2013 with a revised title rather than A3. This is because BSI house rules do not generally permit more than two amendments. Despite appearances this is not a full revision of the document; the bulk of the text remains unchanged but there are a number of technical changes which, whilst small in number, are significant.
The main drivers for change were the findings of the Rose Park care home enquiry; the results of experiments done on the mounting heights of optical beam smoke detectors and aspirating smoke detectors; and the publication of EN 54-23.
Before we look at the technical changes it is worth noting that the title has been extended to make it clear that it only covers ‘non-domestic’ premises. This clearly distinguishes it from -6 which does cover domestic premises.
Two of the findings of the Rose Park inquiry have influenced changes to BS 5839-1; delays in staff locating the fire and delays in summoning the Fire and Rescue Service (FRS). The reviewers looked at these areas for care homes and other premises.
The standard now recommends addressable systems in all but the smallest premises where occupants of a building are going to need assistance from staff to evacuate such as care homes and hospitals. Addressable systems are capable of providing much more specific information about the location of the detection device that has been activated and hence enables staff to go straight to the source of the problem rather than searching for it as would be the case with a non-addressable (conventional) system.
Part of the difficulty in locating the fire at Rose Park was that the zone plan wasn’t clear which, in part, stemmed from disagreements between various parties as to who was responsible for amending it following some alterations. The standard deals with zone plans in a number of ways. It now says that responsibility for supplying the zone plan should be ‘defined at an early stage of the planning of an installation’. It recommends that the installer consults with the designer, the user or purchaser, the supplier of the system and consultants. During these consultations responsibility for providing the zone plan should be settled.
Though not related to care homes but on the topic of zone plans there is a new note which recommends that additional information should be included on the zone plan and talks particularly about shopping centres where occupier details might be helpful. It also makes the important point that this information should be kept up to date. It also now says that before accepting a system, the purchaser (or appropriate representative of the purchaser) should ensure that a suitable a zone plan is provided close to all CIE. It further recommends that when a maintenance organization takes over a maintenance contract that the absence of a zone plan should be reported to the user along with any other non-conformities.
Another one of the problems at Rose Park was the delay in summoning the FRS. The standard now says that automatic transmission of fire alarm signals is necessary in the case of residential care premises it also notes that automatic transmission is a requirement under Scottish building regulation.
Previously the standard recommended that Alarm Receiving Centres (ARC) should be third-party certificated. In addition, it now says that the scope of the certification should include monitoring of fire signals not just security.
The standard now recommends that in residential care premises the FRS is summoned immediately when the fire detection and fire alarm system operates and re-emphasises this saying a staff alarm should not incorporate any delay in summoning of the FRS when the fire alarm system operates. It does say however that there may be a delay in the general alarm signal, provided all staff are made aware of the fire alarm signal.
The minimum sound pressure level (SPL) near the bedhead recommended in BS 5839-1 remains at 75dB(A). This is clearly unreasonable where the occupant of the bed is in no state to help themselves. Previously the standard implied that a lower SPL would have to be agreed among all interested parties. In the new standard these recommendations have been removed. It now simply recommends audible alarms in residential care premises should provide 75dB(A) near the bedhead except where the alarm signal is not intended to rouse occupants from sleep.
Going back a couple of years some tests, partly funded by the FIA, were carried out using Optical Beam Smoke Detectors (OBSD) and Aspiration Smoke Detectors (ASD) in tall spaces. This lead to the section on ceiling heights being changed. Normal sensitivity OBSD and ASD can be used up to a general ceiling height of 25m and 15m respectively; more sensitive variants can be used up to 40m. The standard says that in both cases it should be assumed that stratification will occur in spaces more than 25m high unless there is reason to believe otherwise and additional low level detection would be required: angled beams or low-level (supplementary) detection in the case of OBSD and drop pipes in the case of ASD. The advice on supplementary detection from the previous version remains but no new advice on angled beams or drop pipes is provided. The FIA has a guidance document on ASD which is referenced in the standard and the FIA is working on guidance for angled beams.
Some other changes relating to detection ASD are:
- Sample points may now be flush with the underside of a ceiling
- ASD should be used in racked storage over 8m
- Where ASD is used in dusty or dirty environments they must be fitted with a filter and provided with appropriate maintenance for those filters to prevent false alarms
Where previously selecting Visual Alarm Devices (VADs) was a bit of a guessing game, it is now more of a science. The standard still says ‘the intensity of output of visual alarm devices should be sufficient to attract attention, but not so high as to cause difficulty with vision due to glare’. Previously the system designer would have made a judgement as to the number and type of visual alarms required. However, a new note been added along with a whole new annex. This change was triggered by the publication of BS EN 54-23:2010 ‘Fire detection and fire alarm systems. Fire alarm devices. Visual alarm devices’, which specifies the requirements, test methods and performance criteria for VADs used in fire alarm system. The new edition of the standard calls for VADs to comply with this new standard which requires the manufacturer to provide data on the product which the designer can use to determine the type and location of the VADs. The new standard also calls the designer to use the methodology in the joint LPCB/FIA document CoP 0001, ‘Code of Practice for visual alarm devices used for fire warning’. At first view CoP 0001 looks rather daunting but the process for the selecting VADs is fairly simple.
The mounting height of call points was 1.4m above finished floor level (AFFL) +/- 200mm, giving you a range of 1.2 to 1.6m AFFL. However, accepted practice in buildings used by wheelchair users was that the mounting height of switches and the like was no greater than 1.2m AFFL. With millimetre accuracy you could just satisfy both requirements. However the standard has been amended to give a range of +/-300mm so the mounting height can be between 1.1m and 1.7m AFFL.
The term ‘Responsible Person’ is no longer used. It was considered that the reader may be confused with the term used in English and Welsh fire legislation and which has a radically different meaning.
A broader term ‘Premises Management’ is now used but some still needs to be made responsible for the FD&FA system so the duties remain largely unchanged.
A tiny change in the definition of a Competent Person (designers, installers, maintenance technicians and commissioning technicians) has been introduced. Changing ‘necessary training’ to ‘relevant current training’ serves to underlines the need for update and refresher training.
Part Six
The review of BS 5839-6 was prompted by a general need to update the standard to incorporate changes to other standards and the like to comply with BSI house rules and the findings of the Rose Park Care Home fire inquest. Despite being a new edition rather than an amendment, the bulk of the text of the 2013 version remains unchanged from the 2004 version. The bulk of the changes refer to sheltered housing and there is no mention of care premises.
The new title refers to domestic premises rather than the old title which referred to dwellings. This reflects the scope of the standard which covers the common parts of some forms of multiple tenanted premises. This change is carried through the rest of the document where the preferred term is premises.
When the concept of ‘sheltered housing’ was first conceived such premises would comprise a number of separate dwellings (flats or bungalows for example) occupied by people who, on occasion, would require some practical assistants and where there would always be someone on site to provide that assistance. Increasingly, some premises have taken on some of the appearance of care premises and/or in many instances there is no permanent onsite support. Clearly this has an impact on the risk from fire the tenants are exposed to. The bulk of the changes reflect this.
There is a new sub-section within the commentary of the ‘choice of system’ section which deals with systems for sheltered housing. It points out that many sheltered housing schemes are essentially general needs blocks and that generally there will no evacuation strategy (stay put). People are likely to be slower to evacuate from the flat of fire origin or other flats as directed by the FRS.
With this in mind the standard advises that an occupant of the flat of fire origin should be given the earliest warning of fire by fitting smoke/heat alarms and that, where there is a social alarm system, the smoke/heat alarms are connected to it. The standard gives some general advice on how the social alarm system should function and makes the point that two way voice communication can be used to verify the alarm. The standard also recommends that where there are common areas, such a lounge, that detectors should be fitted to provide adequate time to use the common means of escape and that these detectors should also be connected to an ARC.
There are some changes in the selection and location of detectors in the new CoP. It now recognises that CO and multi-sensor detectors may be beneficial in certain instances. It now adopts a similar approach to detectors in pitched roofs as BS 58390-1. It also now gives recommendations about protecting loft spaces with automatic fire detectors where electrical systems, such as pv solar panel systems and heating systems are fitted.
For further information, go to www.fia.uk.com
About the Author
Phil Martin is Technical Manager at the FIA.
