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 Portable electrical equipment

Portable and transportable electrical equipment (Figure 14.6) is defined by

the regulations as not part of a fixed installation but may be connected to a fixed
installation by means of a flexible cable and either a socket and plug or a spur box or
similar means. It may be hand held or hand operated while connected to the supply or
is intended or likely to be moved while connected to the supply.
The auxiliary equipment, such as extension leads, plugs and sockets, used with
portable tools is also classified as portable equipment. The term "portable" means
both portable and transportable. Almost 25% of all reportable electrical accidents
involve portable electrical equipment (known as portable appliances). While most of
these accidents were caused by electric shock, over 2000 fires each year are started
by faulty cables used by portable appliances, caused by a lack of effective
maintenance. Portable electrical tools often present a high risk of injury, which is
frequently caused by the conditions under which they are used. These conditions
include the use of defective or unsuitable equipment and, indeed, the misuse of
equipment. There must be a system to record the inspection, maintenance and repair
of these tools.

Figure 14.6 - Portable hand-held electric power tools.

Where plugs and sockets are used for portable tools, sufficient sockets must be
provided for all the equipment and adaptors should not be used. Many accidents are
caused by faulty fl exible cables, extension leads, plugs and sockets, particularly
when these items become damp or worn. Accidents often occur when contact is made
with some part of the tool which has become live (probably at mains voltage), while
the user is standing on, or in contact with, an earthed conducting surface. If the
electric supply is at more than 50 V ac, then the electric shock that a person may
receive from such defective equipment is potentially lethal. In adverse environmental
conditions, such as humid or damp atmospheres, even lower voltages can be
dangerous. Portable electrical equipment should not be used in flammable
atmospheres if it can be avoided and it must also comply with any standard relevant
to the particular environment. Air operated equipment should also be used as an
alternative whenever it is practical.

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