Introduction to Health and Safety at Work

17.14.7
Earthing, integrity and other suitable 
precautions – Regulation 8
Precautions shall be taken, either by earthing or by other 
suitable means, for example, double insulation, use of 
safe voltages and earth-free non-conducting environ-
ments, where a conductor, other than a circuit conduc-
tor, could become charged as a result of either the use 
of, or a fault in, a system.
An earth conductor shall be of suffi cient strength 
and capability to discharge electrical energy to earth. The 
conductive part of equipment, which is not normally live 
but energized in a fault condition, could be a conductor.
If a circuit conductor is connected to earth or to any 
other reference point nothing which could break elec 
-
trical continuity or introduce high impedance, for example, 
fuse, thyristor or transistor, is allowed in the conductor 
unless suitable precautions are taken. Permitted devices 
would include a joint or bolted link, but not a removable 
link or manually operated knife switch without bonding of 
all exposed metal work and multiple earthing.
17.14.8 Connections – Regulation 10
Every joint and connection in a system shall be mechan-
ically and electrically suitable for its use. This includes 
terminals, plugs and sockets.
Introduction to Health and Safety at Work
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17.14.9
Excess current protection – 
Regulation 11
Every part of a system shall be protected from excess 
current, for example, short circuit or overload, by a suit-
ably located effi cient means such as a fuse or circuit 
breaker.
17.14.10
Cutting off supply and isolation – 
Regulation 12
There should be suitably located and identifi ed means of 
cutting off (switch) the supply of electricity to any elec-
trical equipment and also isolating any electrical equip-
ment. Although these are separate requirements, they 
could be affected by a single means. The isolator should 
be capable of being locked off to allow maintenance to 
be done safely.
Sources of electrical energy (accumulators, capaci-
tors and generators) are exempt from this requirement, 
but precautions must be taken to prevent danger.