| BS5839: Part 1: 2002 TESTING AND MAINTENANCE
Ensure that all indicators show by resetting according to the instructions
provided with the panel and check that the internal sounder operates.
Operate a manual call point to test the system. Check that the sounders
operate. Reset the fire alarm panel. Each week choose a different
manual call point so that are the manual call points in the building
are tested in rotation over a prolonged period. Check all call points
and detectors and ensure that none are obstructed in any way. Enter
results of tests into the log book.
This consists of multiple checks and tests made by a competent
person with the aim of ensuring the fire alarm system remains functional,
is in good working order and is still compliant with the code.
As per above. Additionally test all detectors and call points and
check for correct operation.
EVERY 2 - 3 YEARS
Clean smoke detectors to ensure correct operation and freedom from
false alarms. Special equipment is required for cleaning smoke detectors.
Replace sealed lead acid batteries. If the operating temperature
exceeds 25oC continuously, then the battery may need to be replaced
Most commercial and industrial premises require a fire detection
system to protect life and property. National and local legislation
cover a variety of buildings and their safety requirements, therefore
it is always advisable to consult the local Fire Prevention Officer
about specific premises. The following guide is intended as a reference
only, and BS 5839 Part 1 2002 should be consulted for all fire system
SYSTEM GUIDELINES - BS5839 Part 1 : 1988 (2003 major changes to
be updated soon)
Type P systems are automatically activated fire detection systems
designed to protect property.
These systems are then sub-divided into:
Type P1 Fire system installed throughout building.
Type P2 Fire system only installed in a defined part of the building.
Type L systems are automatically activated fire detection systems
designed to protect life. These systems are then sub-divided into:
Type L1 Fire system installed throughout building.
Type L2 Fire system only installed in a defined part of the building.
Type L3 Fire system only installed for the protection of escape
Type M systems encompass all manually activated fire systems.
To quickly and accurately identify the fire source, the building
should be divided into zones. Each zone should be accessible from
the main circulation routes leading from the location of the control
panel. If the total floor area of the building does not exceed 300m',
it need only have one zone, no matter how many floors it has. Otherwise,
each floor should be treated as an individual zone. The total floor
area for anyone zone should not exceed 2000m'.
A searcher should not have to travel more than 30m into a zone
for visual indication of the fire's position. The use of remote
indicators outside doors may allow a zone area to be increased.
A fire compartment is an area bordered by a fire resisting structure
with a resistance of at least 30 minutes. If a stairwell or a similar
structure extended beyond one floor but was in one fire compartment,
the stairwell should be a separate zone. If the zone covered more
than one fire compartment, the zone boundaries should follow the
If a building were split into several occupancies, no zone should
ever be split between two occupancies.
If a detector were removed from the zone circuit this must not
isolate a break glass call point on the same circuit.
The type of control panel will depend upon the size of the building
and the extent of the automatic protection provided. The panel is
chosen according to the number of zone and sounder circuits, ancillary
control relays, battery standby time and any other individual customer
The central control panel must be positioned in a low fire risk
area that provides the Fire Brigade with easy access in cases of
emergency. The area must be well lit, therefore provision of emergency
lighting may be necessary. A plan of the building and the zone locations
must be kept beside the control panel.
Choose the correct detector type. With more and more flame retardant
treatments used in building materials and furniture, photoelectric
(optical) smoke detectors tend to be the most popular choice.
Optical smoke detectors are best suited to the detection of slow
burning, smouldering fires caused by materials such as plastic,
PVC or foam. Optical detectors react best to the large smoke particles
produced by such fires and help to avoid false alarms from cooking
fumes etc. Ionisation detectors are the preferred choice for the
detection of the small smoke particles produced by flaming or fast
burning fires, e.g. fires involving liquid fuels. They may be quicker
to respond in the room of the fire's origin. Heat detectors (fixed
heat or rate of rise heat) will provide adequate protection in areas
unsuitable for smoke detectors.
Always ensure detectors are evenly spaced and allow for any obstructions,
such as beams and partitions. Always consider the environmental
conditions - there is a higher risk of false alarms if smoke detectors
are placed in areas of high air movement, or where steam, vapour
or exhaust fumes are likely to be present.
Smoke and heat detectors are placed at the highest points of the
enclosed areas, as this is where smoke and heat from fires is most
The heat sensitive element of a heat detector should be sited between
25mm and 150mm below the ceiling or roof. The smoke detector's sensor
element should be sited between 25mm and 600mm below the ceiling
or roof. If the area has a pitched or north light roof, smoke detectors
should be installed in each apex.
Under flat horizontal ceilings and corridors more than 5m wide,
the maximum horizontal distance between any point in the area and
the nearest detector should be 5.3m for point Heat Detectors, covering
a maximum area of 50m2 and 7.5m for point Smoke Detectors, to cover
a maximum area of 100m2.
The break glass call point allows personnel to raise the alarm
in the event of a fire. Manual call points should be located on
exit routes, including exits to the open air, and on stairwell landings.
They should be mounted 1.4 metres above the floor in easily accessible,
conspicuous positions. Building occupants should not have to travel
more than 30 metres within a building to reach a manual call point.
This maximum distance may need to be reduced if the occupants are
elderly or infirm.
In general, all call points within a building should be of the
same type and operation. Exceptions to this rule would include weatherproof
call points or those designed for use in hazardous areas.
If a call point is to be used on a 240V AC supply the provision
of earth continuity between external circuits is required in order
to comply with paragraph 4.1.7 of BS 5839, Part 2.
Alarm sounders are used to alert and evacuate occupants. They are
normally bells or electronic sounders and all audible warning devices
in the same system must have a similar sound. This distinguishes
them from other audible alarms.
The sound should not permanently damage hearing but it should be
a minimum of 65dBA or 5dBA above any background noise likely to
exceed 30 seconds. Should excessive noise be present, a visual indication
of the alarm condition should also be provided. If the alarm is
to wake sleeping occupants, such as in a hotel, the sound level
should be a minimum of 75dBA at the bedhead. Sound level frequencies
should normally be kept within the range of 500 to 1,000Hz
No matter how small the system, a minimum of two sounders are required
and the correct sound levels must be maintained in all parts of
The sound level is reduced by approximately 20dBA by a door and
by approximately 30dBA by a fire door.
Multiple small sounders produce a better sound distribution than
a few large ones. In some areas, a large number of quieter sounders
may be preferable to a few very loud sounders to prevent noise levels
becoming too loud. Due to individual site characteristics, sound
level checks should be carried out to ensure minimum sound levels
Automatically charged batteries often supply standby power. Automotive
type batteries must not be used. The supply must be able to operate
the alarm for 30 minutes after a certain minimum duration. The minimum
duration varies with type of system and occupancy.
For property protection, if the mains failure is immediately recognised,
a standby duration of 24 hours is required, if not the required
duration is 24 hours longer than the building may remain unoccupied,
For life protection, a standby duration of 24 hours after the fault
is detected is required.
All permissable fire system cables are described in BS5839, Part
1. Fireproof cables are preferred for fire alarm installations.
However, as a minimum they must be utilised for any circuits that
are required to operate after Jetection of a fire e.g. sounder circuits,
power supplies and signalling interconnections. Fireproof cables
require fireproof supporting clips.
Detection circuits may be wired in pvc/pvc e.g. twin and earth
in line with guidelines provided in BS5839, Part 1.
Conductors carrying fire alarm power or signals should be segregated
from conductors used for other systems.
Where possible all cable joints should be made within one of the
system components. If a joint is unavoidable then it should be enclosed
in a suitable reserved junction box labelled "Fire Alarm",
Joints and terminations should only be carried out by competent
Connections to the mains should be via an isolating protective
device e.g. an isolating switch fuse, the cover of the device should
be red and should be labelled "Fire Alarm: Do Not Switch Off",
Cables other than M.I.C.C. should be provided with mechanical protection
when necessary i.e. if physical damage or rodent attack is likely,
or if they are less than 2.25 metres above the floor. Mechanical
protection may be provided by conduit, trunking or by laying in
A commissioning certificate, log book and system diagram are required
to be given to the system user upon the completion of an installation.
After installation, every system should be regularly tested and
serviced. BS5839, Part 1 recommends the following:
Daily (User) - Keep a daily record of faults and report them.
Weekly (User) - Activate a different call point or detector to
check the system, log the details and report any faults.
Quarterly - Check the log book, operate a call point, simulate
faults to check the control panel, visually check for any structural
alterations, and log all details.
Annually - Carry out normal quarterly testing and also test every
detector in situ and ensure all cable fittings are secure.
BS5839 Part 6
The purpose of this simple guide is to assist specifiers and installers
in complying with the recommendations of BS 5839 Part 6 when installing
smoke alarms in dwellings and while every reasonable endeavor has
been made to ensure the accuracy of the information, it is the responsibility
of the reader to ensure that they satisfy the recommendations of
the British Standard in any particular case. No liability is accepted
for the consequences of any errors or omissions in this guide. The
guide is not intended to be a substitute for the British Standard,
the contents of which should be carefully studied by contractors
installing smoke alarms in dwellings. There are a lot of similarities
between the latter part 6 of BS 5839 1995 and the earlier BS 5839
Part 1 for commercial properties but in essence part 1 demands a
fully monitored centrally controlled system with alert devices throughout
the premises achieving at least 65 Db(A) with the following levels
most commonly implicated but there are others.
BS 5839 part 6 covers all residential dwellings, both new and old.
This part applies to bungalows, multi storey houses, individual
flats and maisonettes, mobile homes, sheltered houses, NHS housing
in the community for mentally handicapped or mentally ill people,
mansions and houses divided into several self contained family dwelling
units. It does not apply to hostels, caravans or boats (other than
permanently moored boats used solely as residential premises), or
to the communal parts of purpose built sheltered housing and blocks
of flats or maisonettes. Compliance with the standard does not of
itself confer immunity from legal obligations.
The British Standard recommends that all smoke alarms should conform
to BS 5446 : Part 1. It also recommends that they should have been
type tested, and preferably have been approved under a recognised
approval scheme. All TTS smoke alarms fully meet the requirements
of BS 5446 : Part 1 and have BSI kitemark and CE approval. This
facilitates incorporation of a domestic heat detector, which can
be used to trigger a nearby smoke alarm to which it is wired. Heat
detectors are very much slower in their response to fire than smoke
detectors. They should only be used as supplementary protection
to smoke alarms, in rooms, such as kitchens, where constant false
alarms would occur if smoke alarms were installed (or, less commonly,
in rooms in which a fire would not cause an early threat to escape
routes). In particular, heat detectors should never be installed
in circulation spaces that form escape routes from the house; smoke
alarms must be used in these areas.
It should first be ensured that standard smoke alarms are a suitable
form of fire detection. Smoke alarms are suitable for most flats,
maisonettes and single or two storey houses (including houses in
multiple occupation) unless they are:
(i) very large (more than 200 m² on any floor);
or (ii) unusually high (with the upper floor more than 4.5m above
Larger properties need a form of fire detection and alarm system
with a central control panel. The system then becomes BS 5839 Part
1 design. However, in a house in multiple occupation, regardless
of size, smoke alarms may be used to give warning to occupants of
a fire in their own accommodation, while communal escape routes
are protected by a full fire detection and alarm system.
For new dwellings, battery operated smoke alarms should not be
used. These should only be used for retrofitting in existing bungalows,
flats and owner occupied two storey houses in which there is adequate
means of escape in the event of fire. Mains operated smoke alarms
should be used for all new dwellings and for retrofitting in rented
maisonettes and two storey houses. (They should also be used for
single storey bungalows and flats if, for example, occupants could
be trapped in a lounge, dining room or bedroom, due to a fire in
another room through which it is necessary to pass in order to escape
from the property; this might occur if, for example, there is a
bedroom off a lounge, and there is no window in the bedroom suitable
for escape.) Mains operated smoke alarms should also be used in
preference to battery operated devices if the occupants are considered
to be at high risk from fire or if they may not be able to replace
batteries soon after a low battery fault warning is given.
Both the ionisation chamber and optical smoke alarms have a wide
application range, and either type will be effective in giving a
sufficiently early warning of fire in many circumstances. However,
the optical smoke alarm responds better to some types of fire than
the ionisation chamber type, whereas other fires are more readily
detected by the ionisation chamber smoke alarm. Avoidance of false
alarms may also dictate the use of one type of smoke alarm in a
particular location, rather than the other. The most common cause
of false alarms is fumes generated by cooking. Optical smoke alarms
are generally less sensitive to, for example, smoldering toast than
ionisation chamber smoke alarms (although the optical smoke alarm
will respond if the toast catches fire). Because of this, BS 5839
: Part 6 recommends that the smoke alarm nearest to a kitchen should
be of the optical type. For effective fire detection, the British
Standard also recommends that optical smoke alarms should be used
in the circulation areas of the house. Accordingly, to comply with
the British Standard, optical smoke alarms should be used in the
hallways and staircases. This should be particularly noted if compliance
with the British Standard is a requirement of a building control
In other locations, smoke alarm choice should depend mainly on
the type of fire that may be expected. In many cases, this will
be something of an unknown, and, often, either type of detector
can be used. Under these circumstances, avoidance of false alarms
should be taken into account. In some dwellings, electricity supplies
may be disconnected because the occupiers are unable to pay for
supplies. Disconnection may be at a coin or card operated meter
or may be due to deliberate disconnection by the supplier. If this
is likely to occur, smoke alarms with battery back-up should be
installed. In practice, in many cases, there will be insufficient
information regarding the occupiers, who may, in any case change.
Accordingly, TTS recommend the use of smoke alarms with battery
back-up in most circumstances, as is now quite common practice.
Connection to Mains Supply
Warning: Installation of mains powered smoke alarms should be undertaken
only by a qualified electrician. Installation should be undertaken
in accordance with BS 5839 : Part 6 and BS 7671 (IEE Wiring Regulations).
Mains-only smoke alarms with no battery back-up should be connected
on a single independent, dedicated circuit at the dwelling’s
distribution board. No other electrical equipment should be connected
to this circuit. The circuit should preferably not be protected
by any r.c.d., whether dedicated to the circuit or common to all
circuits derived from the distribution board. If, however, r.c.d.
protection is essential for electrical safety, the British Standard
recommends two options:
(i) The r.c.d. should be dedicated to the smoke alarm circuit (which
should then not be served by any other r.c.d.);
(ii) The r.c.d. protection should be arranged so that the r.c.d.
serving the smoke alarm circuit operates independently of any r.c.d.
protection for circuits supplying socket outlets or portable equipment.
(For example, this could be satisfied by a distribution board with
a time delayed 100mA r.c.d. serving the entire board, and 30mA r.c.d.
protection on socket outlets, etc. It would be expected that, in
the event of earth leakage on a socket outlet circuit, the 30mA
r.c.d. would operate without the 100mA r.c.d. necessarily operating.)
BS 5839 : Part 6 recommends that there be a method of silencing
or disabling smoke alarms in the event of a prolonged false alarm,
perhaps due to a fault or a build p of pollution in the detector
chamber. However, to comply with BS 5839 Part 6, there must be a
means of silencing or disablement. This recommendation can be satisfied
if the dedicated circuit serving the smoke alarms is protected by
a miniature circuit breaker (as opposed to a fuse); the British
Standard recognizes a miniature circuit breaker as a suitable and
readily accessible means of silencing.
Because of the back-up batteries, these smoke alarms can be connected
(i) a single dedicated circuit at the distribution board.
(ii) a separately electrically protected, regularly used local
lighting circuit. However, if the smoke alarms are connected to
a lighting circuit, isolation of the detector for maintenance may
be less convenient due to the need to isolate the lighting circuit.
For models with battery back-up, the British Standard does not
specifically recommend against r.c.d. protection of the relevant
circuit. However, TTS would still advise that it be ensured that
the circuit used is not subject to nuisance tripping due to r.c.d.
Interconnection of Smoke Alarms
If two or more smoke alarms are installed, they should normally
be interconnected to maximise the extent of the audible warning
when one detects a fire. In new dwellings, smoke alarms should always
be interconnected. It is essential that interconnected smoke alarms
are all supplied from a single common circuit.
All wiring should be installed in accordance with BS 7671 (IEE
Wiring Regulations). The wiring of smoke alarms need not be fire
resisting. The mains supplies, and any interconnections between
smoke alarms, may be wired in any suitably rated cable designed
for a.c. mains installations. However, care should be taken to ensure
that the mains supply cable, and the cable used for interconnection
of smoke alarms, is not exposed to damage. BS 5839 : Part 6 recommends
that the cables are protected, by for example capping under plaster,
conduit, or trunking, in any areas where they may be subject to
impact, abrasion or rodent attack.
Where cables pass through walls, a smooth clearance hole should
be provided. If additional mechanical protection is necessary, a
smooth-bore sleeve should be sealed into the wall. Care should be
taken to ensure that the ends of the sleeve are free from sharp
edges. Cable penetrations should be filled and should maintain the
fire resistance of any fire resisting walls or floors. Joints in
cables should be avoided but, where unavoidable, should be enclosed
in a suitable and accessible junction box. Reliable termination
methods should be adopted.
Grades of System
BS 5839 : Part 6 defines various ‘Grades’ of system.
These will be used by enforcing authorities and specifiers to specify
the type of fire detection equipment that is to be installed. Smoke
alarms can be used in Grade C*, D, E and F systems, which are suitable
for protection of most normal flats, maisonettes and houses.
Grade F systems comprise one or more battery-powered smoke alarms.
Grade E systems comprise one or more mains-powered smoke alarms.
Grade D systems comprise one or more mains-powered smoke alarms,
each with an integral standby supply, such as a battery.
The grades are intentionally defined in such a way that higher
grades are always of a better standard than lower grades. So, if
a specification calls for a Grade F system, this can always be satisfied
by installing mains powered smoke alarms. Similarly, if a specification
calls for a Grade E system, the requirement can be satisfied by
installing mains-powered smoke alarms either with or without battery
Grade C systems comprise one or more smoke detectors / alarms with
a central control panel, however, Grade C systems may also comprise
12V smoke detectors integrated with an intruder alarm system, subject
to the integrated system complying with BS 5839: Part 6. Grade A
and B systems are not considered in this Guide. Smoke alarms cannot
be used to satisfy the recommendations of the British Standard for
Grade A or B systems; these systems use complete fire detection
and alarm systems with separate detectors, sounders and control
equipment. TTS Fire & Security Ltd. has a comprehensive range
of radio fire detection products for Grade A and B systems. TTS
should be consulted for guidance on the design of these systems,
which require to be more ‘tailor made’ for the particular
Although BS 5839 : Part 6 recommends type LD3 protection as the
minimum standard of protection for those single-family dwellings
in which smoke alarms are suitable, it should be stressed that the
Standard recommends the installation of additional smoke alarms
(so providing LD2, or in some cases even LD1, protection) if: The
risk to occupants is higher than in a ‘typical’ dwelling.
Possible examples could be the need for smoke alarms to be installed
in living rooms and dining rooms if the occupiers smoke, or in bedrooms
if they smoke in bed. It might also be appropriate to install smoke
alarms in rooms, particularly bedrooms, in which portable heaters
or solid-fuel fires are used during the night, or in which electric
blankets are used, particularly by high-risk groups such as the
elderly. Houses in which the principal occupant is elderly or in
which there are several elderly occupants or young children may
warrant additional smoke alarms. If occupants’ mobility is
impaired, additional smoke alarms may also provide greater time
for them to escape in the event of fire. The means of escape from
the dwelling suffers from some shortcoming. A particular example
would be a lounge, dining room or bedroom with no suitable window
for escape, located off another room e.g. a bedroom off a lounge.
A fire in the lounge could trap people in the bedroom, and a smoke
alarm should be provided in the lounge to give early warning of
Where any doubt exists as to the need for, or appropriate locations
of, additional smoke alarms, the advice of the fire brigade or other
fire safety specialists should be sought. Advice can also be provided
by the TTS Fire & Security Ltd.
Locating and Siting Smoke Alarms
Smoke alarms should be sited in accordance with the following guidance
to ensure both adequate detection and alarm sounder audibility:
¯ At least one smoke alarm should be located between the sleeping
areas and the most likely sources of fire (living room and kitchen).
¯ In a single storey dwelling, one smoke alarm may be sufficient,
in which case it should be sited as close as possible to the living
accommodation. If there are rooms (other than toilets, bathrooms
or shower rooms) on either side of a bedroom, a smoke alarm should
be sited in the hallway, mid-way between these rooms.
¯ In a two storey house, at least one smoke alarm should be
located on each storey. In a conventional two storey house, one
smoke alarm should be sited on the ground floor between the staircase
and any room in which fire might start. A further smoke alarm should
be sited on the upstairs landing.
¯ Additional smoke alarms should be provided in long hallways
of all dwellings. Within such circulation areas, no door to any
room should be further than 7.5 m from the nearest smoke detector.
In open-plan accommodation, where a stair may be open to a living/dining
area, the living/dining area should be treated as a circulation
¯ Under flat ceilings, the distance from any point in the
room or area that is to be protected to the nearest smoke alarm
should never be more than 7.5 m. (or 5.3 m in the case of a heat
detector). Smoke alarms should preferably be mounted on ceilings,
unless the ceiling temperature is likely to be significantly greater
than the general air temperature. If ceiling mounting is not possible,
wall mounting may be considered in small rooms or short hallways.
However, smoke alarms should not be mounted on poorly insulated
If smoke alarms are mounted on walls in small rooms or short hallways,
they should be mounted so that:
the smoke entry grille is between 150 mm and 300 mm below the ceiling;
and the smoke entry grille is above the top of any doorway. Smoke
alarms should not be mounted adjacent to, or directly above, heaters
or air-conditioning vents. Smoke alarms should be sited in positions
that are reasonably accessible, particularly in the case of models
containing batteries, so that the False Alarm Control (‘hush
button’) can be operated and that the smoke alarm may be de-mounted
to change batteries. Smoke alarms should not be located closer than
300 mm to walls or light fittings. In order that the smoke alarms
will wake people from sleep, there is a need to ensure that there
is a smoke alarm within 3 m of each bedroom door.
The above guidance will ensure only protection of circulation spaces
(a type LD3 system). Such protection cannot be depended upon to
save the life of anyone in the room in which fire starts. In many
circumstances, the risk of fire may justify a type LD2 or LD1 system.
This will necessitate detectors (whether heat or smoke) in some
rooms of the dwelling. In houses of multiple occupancy a manual
call point should be installed by exit doors and on each floor level.
Occasional false alarms from smoke alarms are inevitable, but installers
should site smoke alarms in such a way as to avoid unnecessary false
alarms. However, avoidance of false alarms should never take precedence
over effective fire detection. Guidance on selection of the most
suitable type of smoke alarm in order to provide optimum fire detection
while avoiding unnecessary false alarms. Note that the smoke alarm
nearest to any kitchen should be of the optical type. This will
normally be the case, because all smoke alarms in circulation spaces
should normally be of the optical type. However, optical smoke alarms
should not be sited close to bathrooms, showers or rooms from which
steam may escape. Nevertheless, because these rooms normally open
off circulation spaces, false alarms should normally be avoided
by careful siting of the smoke alarms, rather than using ionisation
Alarm Sound Levels
It is essential that, whenever any of the smoke alarms in the dwelling
detects a fire, the sound level of the alarm (from either that smoke
alarm or other smoke alarms interconnected with it) is sufficient
to wake up at least the adult members of the household. The sound
level in any bedroom is likely to be satisfactory if there is a
smoke alarm in the bedroom, interconnected to all other smoke alarms
in the dwelling. However, if this is not the case, the nearest interconnected
smoke alarm to the bedroom, capable of sounding an alarm whenever
fire is detected anywhere in the dwelling, should not be further
than 3 m from the bedroom door.
In some dwellings, such as flats, maisonettes and houses in multiple
occupation, doors to rooms may be fire doors, which tend to attenuate
the sound from smoke alarms more than normal, domestic doors. In
these cases, great care should be taken to ensure that the sound
level in bedrooms is sufficient. In some houses in multiple occupation,
the local authority may demand that the sound level at the bedheads
in some or all bedrooms is 75dB(A) when the bedroom doors are closed.
This should be determined before finalising the number of smoke
alarms required, because 75dB(A) is unlikely to be produced at the
bedhead unless there is a smoke alarm within the bedroom.
If occupants suffer from severe hearing impairment, BS 5839 : Part
6 recommends that special alarm devices, such as high intensity
beacons and vibrating pillow or mattress pads, be provided. User
Instructions Occupiers should be provided with suitable instructions
on the smoke alarms installed. BS 5839 : Part 6 sets out the information
that should be contained in these instructions.
Once the installation has been completed and instructions have
been handed over to the occupier (or the owner in the case of a
house in multiple occupation), a certificate of compliance with
BS 5839 : Part 6 should be issued. It should be noted that, because
BS 5839 : Part 6 is only a code of practice, as opposed to a rigid
set of regulations, it may have been appropriate to deviate from
its recommendations, subject to the agreement of the purchaser and
any relevant enforcing authority (normally building control in the
case of new dwellings or the environmental health officer in the
case of houses in multiple occupation). The certificate should specify
the type and grade of system, and should indicate any deviations
from the recommendations of the British Standard in respect of this
type and grade of system. A model installation certification is
contained in BS 5839 : Part 6. The IEE Wiring Regulations further
require the issue of a certificate for the entire electrical installation
in the case of a new house.