PSI July 2019

FIRE SAFETY
Andy Speake is National
Technical Manager at Aico, a Fire
Industry Association member
company. Andy works closely
with a number of leading
industry organisations and helps
with research and development
of new products.
ii
Improved protection
and clarification
Andy Speake looks at the revised
British Standard for domestic fire
alarms
For those of you who are involved – or BS 5839-
6 is the code of practice for the design,
installation, commissioning and maintenance
of fire detection and fire alarm systems in domestic
premises. When it was first introduced in 1995, BS
5839-6 it changed everything. Whether you were a
landlord, a specifier or an installer, here at last was
a clear and detailed set of standards to be
observed. The contents of BS 5839-6 were quickly
adopted and have been standard practice since
then in both existing dwellings and new builds.
Building Regulations and other guidance
documents reference this standard, so its
importance cannot be over emphasised.
BS 5839-6 was revised in 2004 and then again
in 2013, both times taking into consideration
technological developments and revising best
practice accordingly. It’s been around a decade
between each set of revisions so why, just six years
since the last set of revisions, was a new version
released this year on the 30th April?
The answer isn’t to be found in new technology
but in the will of professionals in housing, fire and
safety to improve the level of fire protection in
domestic dwellings, which ultimately provides
residents with a greater chance of escape
unharmed from a fire in their home.
Whilst there have been a number of minor
revisions within BS 5839-6:2019, plus multiple
definitions that have been updated throughout, the
biggest changes by far apply to the grades of
alarms and the type/level of protection for each
identified dwelling. The Grade determines the type
of alarm to be used and the Category the level of
protection required.
Changes to Grades
Under BS 5839-6, Fire Alarms are classified into
Grades, from A to F. Grades B and E have been
removed in 2019, but with Grade D being the
current most common for domestic properties that
will form the focus of this piece.
Under the previous standard, Grade D required
one or more interlinked mains powered Smoke
Alarms (and Heat Alarms if required), each with an
integral back-up supply; the back-up supply to be in
the form of a rechargeable lithium or alkaline battery.
Under the revised BS 5839-6, Grade D has been
replaced with Grades D1 and D2 which differ in
terms of the back-up power supply:
• D1 calls for a tamper-proof standby supply
consisting of a battery or batteries, with lithium
being the standard battery type. These are long
life battery cells lasting the recommended lifespan
of the alarm and are designed so they cannot
easily be removed by the user. Grade D1 alarms are
the preferred option for social housing as they
remove the risk factor.
• D2, on the other hand, requires an integral
standby supply consisting of a battery or batteries
(usually 9 volt PP3) which need to be replaced at
regular intervals throughout the life of the alarm by
the user.
Changes to these Grades provides greater
clarity for alarm specifiers and installers, which is
welcomed.
Whilst Grade D alarms feature most heavily in
BS 5839-6:2019 Grade F systems also warrant
mention here due to changes in Scottish legislation
earlier this year which permits their use. Grade F
systems use battery only powered alarms. As with
Grade D, Grade F has now been divided into F1 and
F2 in the same fashion as that noted above.
Property Types Get New
Minimum Levels of protection
Under BS 5839-6 different classes of premises are
identified and the minimum Grade of fire alarm
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