In 2019 a full revision of BS 5839-6 was published by the British Standards Institution (BSI). As with all British Standards, other than BS 7671 (IET Wiring Regulations), there is no lead time period for the implementation between the old and new standard and, therefore, BS 5839-6: 2013 was superseded and withdrawn with immediate effect in April 2019. All new work relating to fire detection and fire alarm systems in domestic premises had to comply with the relevant recommendations of BS 5839-6: 2019.
BS 5839-6 is a standard whose scope is to give recommendations for the design, installation, commissioning, and maintenance of premises designed to accommodate a single family, for houses in multiple occupation (HMOs), sheltered housing and supported housing. It does not provide guidance and recommendations for the communal areas or ancillary accommodation, such as plant rooms and the like.
Post-Grenfell there have been instances where temporary fire detection and fire alarm systems have been installed in blocks of flats where the exterior cladding does not satisfy the requirements of building regulations in relation to the rate of fire spread over external walls. Such fire detection and fire alarm systems are intended to be of a temporary nature and are expected to be removed from service once the cladding has been either removed or made safe; such systems are outside the scope of BS 5839-6.
Grades and Categories of fire alarm system
The Category of a system defines the type of fire detection and fire alarm system necessary for a particular purpose, such as protection of life or protection of property. The Categories detailed in clause 8.1.1 of BS 5839-6 are LD1, LD2, LD3, PD1 and PD2.
The Category of a system defines the type of fire detection and fire alarm system necessary for a particular purpose, such as protection of life or protection of property. The Categories detailed in clause 8.1.1 of BS 5839-6 are LD1, LD2, LD3, PD1 and PD2.
However, it has been clear for quite some time that very few Grade B and E fire detection and fire alarm systems are designed, installed and commissioned within the UK. BS 5839-6: 2019 reflects the reality that Grade B and E systems are not utilised and, therefore, the Grades of system have been simplified and are now graded as A, C, D1, D2, F1 and F2. While the definition of Grade A and Grade C systems has not changed, there have been some changes to the definitions of Grade D and F systems.
D1 A system of one or more mains-powered detectors, each with a tamper-proof standby supply consisting of a battery or batteries.
D2 A system of one or more mains-powered detectors, each with a tamper-proof standby supply consisting of a user-replaceable battery or batteries.
F1 A system of one or more battery-powered detectors, powered by a tamper-proof primary battery or batteries.
F2 A system of one or more battery-powered detectors, powered by a user-replaceable primary battery or batteries.
Both the D1 and F1 Grades of system avoid the risk of an occupier permanently silencing a smoke/ heat/multi-sensor alarm, with a long-life battery being permanently installed in the alarm. It is likely that such a battery/batteries will be of the long-life (lithium-ion)1 type. With the reduction in Grades of system a designer will have to decide, based on the risk assessment carried out, whether to design and install a Grade A/C system instead of a Grade B, and whether a Grade E system should be Grade D1/2 or F1/2.
BS 5839-6 Table 1
Table 1 of BS 5839-6 shows the recommended minimum grade and category of fire detection and fire alarm system for the protection of life in a wide range of typical premises. This table has been significantly amended and expanded and makes clear the differentiation between privately owned and rented sector premises.
It should be noted that there is an uprating in the recommended Category of system from LD2 to LD1 for new or materially altered sheltered housing flats2 and new recommendations for fire detection in supported housing.
The minimum recommended Grade of system for single-storey and two or more storeyed supported housing premises3 having no more than four bedrooms is D1, LD1. For two or more storeyed supported housing premises having more than four bedrooms, the minimum recommended Grade and Category of system is A, LD1.
Grade C Fire alarm systems
A Grade C system has a common power supply containing both a normal and a standby supply. A Grade C system may also be integrated with another system, such as an intruder alarm or social alarm system.
The updated Standard has revised and expanded the recommendations for Grade C systems and made the design and installation of such a system an option where it is desired to be able to automatically transmit a fire alarm signal to the fire and rescue service.
Where a Grade C system is integrated with another system and both systems share a single communication link to an alarm receiving centre (ARC), the transmission system should be designed such that the fire alarm signals can be separately identified at the ARC.
Fire alarm signals transmitted to an alarm receiving centre (ARC)
Where there is a high risk to life or a desire to protect property in the case of Category PD systems, it is necessary for the fire and rescue service to be called at the earliest possible opportunity while limiting the risk of false alarms.
Clause 20.2 of BS 5839-6 details the recommendations for the remote transmission of alarm signals and has been updated as follows:
c) to include changes where a scheme manager is on-site or is off-site
d) provide greater clarity regarding the facility for automatic transmission of fire alarm signals to the fire and rescue service, including the avoidance of false alarms, measures to prevent false alarms, and the possible need for the fire and rescue service to force entry to an unoccupied premises in the event of a false alarm
g) to prevent the use of automatic fire alarm signal transmission unless a contract is in place for maintenance of the system at periods not exceeding six months
h)1) where alarm signals are transmitted to an ARC, to reduce the delay when determining a false signal from two minutes to 60 seconds
k) to change the reference from BS 5979 to BS 8591, Remote centres receiving signals from alarm systems – Code of practice
m) NOTE 7 added to enable two enclosures not more than 50 mm apart to still align with m).
BS 5839-6 Table 3
Table 3 of BS 5839-6 is a new table detailing the testing and servicing recommended by Grade of System. Reference to this table is a new recommendation found in Clause 26.2b) of BS 5839-6.
Table 3 recognises that a distinction can be made between those checks that can be sensibly made by a user and those that should be made by a competent person.
Grade A systems should be tested and serviced in accordance with the recommendations detailed in BS 839-1: 2017.
Grade C systems should typically be tested and serviced in accordance with manufacturer’s instructions, otherwise in accordance with Annex I of BS 5839-6 where applicable.
Smoke alarms, heat alarms and multi-sensors in Grade D and Grade F systems should have their test buttons pressed monthly by the user and, where serviced by a competent person, in accordance with the recommendations of Annex I of BS 5839-6 where applicable.
There may exist specific regulatory requirements within various parts of the United Kingdom, and these must also be met.
BS 5839-6 Clause 27
Clause 27 is a new clause recommending that a logbook is issued for Grade A systems and for sheltered and supported housing installations irrespective of their Grade and Category of system; enforcing authorities may wish to have sight of such documentation under fire safety legislation. Clause 27 details the minimum information that should be recorded in such a document as follows:
the name of the person in the premises who is responsible for the fire detection and fire alarm system.
brief details of the maintenance arrangements.
dates and times of all fire alarm signals.
causes, circumstances surrounding and category of false alarm.
dates, times and types of all tests.
dates, times and types of all faults and defects; and
dates and times of all maintenance.
Summary
A number of significant changes have been made to BS 5839-6 and it is essential that all those designing, installing, maintaining and servicing fire detection and fire alarm systems in domestic premises are fully conversant with the new standard and, where necessary, have undertaken the necessary technical training.
All designers and installers need to make use of the updated certificates and logbooks and, although installations designed and installed to the previous Standard can still be certified to that standard, all installations should now be designed, installed, maintained and serviced in line with the 2019 Standard.
The Practical Guide to Grade-D Fire Alarm Systems was written to give the reader a clear understanding of their roles and responsibilities, whether that be as a contractor, designer, landlord or housing manager, and provides a suitable context in which all such work should be carried out. The book is written in a clear and concise style and covers all aspects relating to competence, fire risk assessment, design, installation, commissioning, and maintenance.
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