Introduction
This guidance is for people, including the self-employed, who carry out work on
or near electrical equipment. It includes advice on safe working practices for
managers and supervisors who control or influence the design, specification,
selection, installation, commissioning, maintenance, or operation of electrical
equipment. Organizations that already have industry-specific rules or guidance for
safe working practices should ensure that all aspects addressed in this guidance
are adequately covered. Those that have no such internal rules should use this
guidance to devise safe working practices relating to their own specific
circumstances and activities.
The Electricity at Work Regulations 1989 (EAW Regulations) apply to almost all
places of work. The Memorandum of guidance on the Electricity at Work
Regulations 19891 (the Memorandum) is intended to help duty holders meet the
requirements of the Regulations. This guidance supplements the Memorandum with
further advice on safe working practices. Where regulation numbers are given in
Figures 1–5, refer to the EAW Regulations. There is also an Approved Code
of Practice covering the use of electricity at mines that provides additional guidance
relevant to mining.2 Other legislation can also apply to electrical work and some of
this is listed in the ‘References’ or ‘Further reading’ sections, as are all other
publications referred to in this guidance.
Definitions
Charged:
the item has acquired a charge either because it is live or because it
has become charged by other means such as by static or induction charging,
or has retained or regained a charge due to capacitance effects even though it
may be disconnected from the rest of the system;
Dead:
Not electrically ‘live’ or ‘charged’;
Designated competent person (also known in some industries as
‘authorized person’ and ‘senior authorized person’):
A competent person appointed by the employer, preferably in writing, to undertake certain specific
responsibilities and duties, which may include the issue and/or receipt of safety
documents such as permits to work. The person must be competent by way of
training, qualifications, and/or experience and knowledge of the system to be
worked on;
Disconnected:
Equipment (or a part of an electrical system) that is no connected to any source of electrical energy;
Equipment:
Electrical equipment including anything used, intended to be used
or installed for use, to generate, provide, transmit, transform, rectify, convert,
conduct, distribute, control, store, measure or use electrical energy (as defined
in the EAW Regulations);
High Voltage:
A voltage in excess of 1000 V ac or 1500 V dc. Voltages below
these values are ‘low voltage.
Isolated:
Equipment (or part of an electrical system) that is disconnected and
separated by a safe distance (the isolating gap) from all sources of electrical
energy in such a way that the disconnection is secure, ie it cannot be
re-energised accidentally or inadvertently.
Live:
Equipment that is at a voltage by being connected to a source of
electricity. Live parts that are uninsulated and exposed so that they can be
touched either directly or indirectly by a conducting object are hazardous if the
voltage exceeds 50 V ac or 120 V dc in dry conditions – see BSI publication PD
65193 – and/or if the fault energy level is high.
Live Work:
Work on or near conductors that are accessible and ‘live’ or
‘charged’. Live work includes live testing, such as using a test instrument to
measure voltage on a live power distribution or control system.
What Are The Hazards?
Electricity can kill or severely injure people and cause damage to property from
the effects of fires and explosions. Every year accidents at work involving electric
shock or burns are reported to the Health and Safety Executive (HSE). Electric
shocks do not always cause lasting injury but in certain circumstances can result in
death, known as electrocution. The sudden muscular contraction during the shock
can result in injuries from, for example, falling. Electric current flowing through the
body can cause deep burns.
Electrical arcing (sometimes called a ‘flashover’ or ‘arc flash’), perhaps as a
result of a short circuit caused by unsafe working practices, can generate intense
heat leading to deep-seated and slow-healing burns, even if it persists for a short
time. The intense ultraviolet radiation from an electric arc can also cause damage to
the eyes. Often those working with or near electricity do not appreciate the risk of
serious injury and consequential damage to equipment that can arise from arcing.
Arcing, overheating and, in some cases, electrical leakage currents can cause
fire or explosion by igniting flammable materials. This can cause death, injury and
considerable financial loss.
Most electrical accidents occur because people are working on or near
equipment that is:
■ Thought to be dead but which is live;
■ Known to be live but those involved do not have adequate training or
appropriate equipment to prevent injury, or they have not taken adequate
precautions.
Correct Selection & Use Of Equipment
Equipment must be properly designed, constructed, installed and maintained
so that it does not present a risk of electric shock, burns, fire or explosion when
properly used. There are many equipment-specific standards that include safetyrelated
requirements which, if followed, will ensure that the electrical risks are
adequately controlled.
The main standard for low-voltage electrical installations is BS 7671
Requirements for electrical installations.4 It describes how systems and equipment
can be designed, constructed and installed so that they can be used safely. The
standard covers installations that operate at low voltage (up to 1000 V ac). Meeting the
requirements of this standard is likely to achieve compliance with the relevant parts
of the EAW Regulations.
Some old equipment that is still in use, including open-type switchboards and
fuseboards used by electricity distributors and in industrial premises such as
steelworks, is not designed or constructed to prevent people touching live
conductors and suffering injuries from shock or burns. In these cases, the user
must have sufficient knowledge and experience to recognise the danger and avoid
it. This type of equipment should be located in a secure room or area, with access
available only to those who have specific authority and are competent to prevent
danger. Even then, you will need to further protect this type of open, uninsulated
equipment to prevent accidental contact with live parts when competent persons
are working near it.
Some equipment operates at voltages that are so low that they cannot cause a
harmful electric shock but even at these extra-low voltages an arc can occur, burns
can result from overheated conductors, or an explosive atmosphere can be ignited.
A short-circuited car battery, for example, may cause the conductors to overheat
and even cause the battery to explode. The following advice also applies to selfcontained
sources of electrical energy, whether the risk is from electric shock, burn,
arcing, or explosion.
You must select equipment that is suitable for the environment in which it is
used, for example, cables and equipment in heavy industries such as sheet metal
works need to be protected against mechanical damage. You should consider
adverse environmental factors when working on equipment. For example,
excessively damp or humid conditions will increase the risk of injury because of
the reduced effectiveness of insulation, which may undermine the effectiveness of
devices used for isolation, or increase the severity should an electric shock occur.
Equipment that has corroded may not function as intended.
You must assess the situation before work is carried out on or near the equipment.
Working on equipment may result in the removal of components and parts that provide
protection for people against electric shock when the equipment is in normal use.
You should ensure safety by the careful design and selection of electrical
equipment. For example:
- Switch disconnectors should have a locking-off facility or other means of
- Securing them in the OFF position;
- Circuits and equipment should be installed so that all sections of the system can be isolated as necessary;
- Switch disconnectors should be suitably located and arranged so that circuits and equipment can be isolated without disconnecting other circuits that are required to continue in service;
- Devices used for isolating circuits must be clearly marked to show their relationship to the equipment they control unless there could be no doubt that this would be obvious to anyone who may need to operate them.
Where possible, you must avoid live working during commissioning and faultfinding;
eg by using suitably designed equipment with in-built test facilities and
diagnostic aids. There must be adequate space, access, and lighting to work safely.
Temporary systems and equipment should be designed, constructed, installed, and
maintained to avoid danger.
Actions for Managers & Supervisors
Managers should establish a system of rules and procedures wherever
electrical work is to be carried out, or ensure that contractors brought in to do
electrical work have appropriate rules and procedures. These should be written
down and everybody involved must be made aware of them as they will form the
basis of task-specific risk assessments. The amount of detail depends on the
circumstances; the simplest form may be a brief policy statement (perhaps
reflecting a policy of always switching off, securing the isolation, working dead, and
never working on live equipment) backed up by a set of simple instructions to
reflect that policy. Where there are extensive or complex electrical systems,
especially high-voltage systems, this will be reflected in the safety rules, which
should embody a methodical approach so that the safety principles involved can be
clearly understood by everyone.
Safety rules should set out the principles and general practices clearly and in a
compact format. Those carrying out the work should be instructed to carry the
safety rules with them. Workers should know the limitations of their work allowed
under the safety rules. Detailed procedures for safe working on particular
equipment, or under particular circumstances, should be the subject of separate
documents, including task-specific risk assessments or method statements, which
should be readily available when required (even in out-of-hours emergencies).
These safety rules should be devised to reflect, among other things, the relevant
organization, personnel, the electrical system to be worked on, and the working
environment. Further guidance can be obtained from three British Standards.
BS – 6423,9 BS 662610 and BS 6867.
If you have managerial or supervisory responsibilities, it is important that you
ensure that everyone knows how to work safely and without risk to their health, and
that all workers follow the safety rules and control measures identified in risk
assessments:
You should be involved in planning the work and in the risk assessment
process, coordinating the work where more than one group is involved, and
discussing the necessary precautions and emergency procedures with the
workers.
You must clearly define the roles and responsibilities of the supervisors and
workers, including those of any contractors who may be employed.
You must ensure that supervisors are competent to supervise the work, with
the level of supervision is appropriate to the danger and the competence of
those carrying out the work.
Deciding Whether To Work Dead or Live
Can the normal policy of dead working be carried out?
The factors to consider are illustrated in Figure 2. Work on or near live exposed
conductors should rarely be permitted. Many accidents to electricians, fitters,
technicians and engineers occur when they are working on equipment that could
have been isolated. You should plan and program the work to allow all jobs to
be carried out where possible with the equipment dead. Three conditions must be
met for live working to be permitted where danger may arise. If just one of these
conditions cannot be met, live working must not be permitted and dead
working is essential. The assessment procedure illustrates this. The conditions
are:
■ It is unreasonable in all the circumstances for the conductor to be dead; and
■ It is reasonable in all the circumstances for the person to be at work on or near
that conductor while it is live; and
■ Suitable precautions (including, where necessary, the provision of personal
protective equipment) have been taken to prevent injury.
Is it unreasonable for the work to be done dead?
There are some circumstances where it is unreasonable to make equipment
dead because of the difficulties it would cause. For example:
■ it may be difficult, if not impossible, to commission a complex control cabinet
without having it energized at some time with parts live (but not exposed so
that they may be easily touched);
■ it may not be technically feasible to monitor the operation and performance of a
control system or to trace a malfunction of such equipment with it dead, ie
fault-finding.
Identify, Assess & Evaluate The Risks & Methods For Controlling Them
If you have decided that it is unreasonable for the work to be done dead, a risk
assessment is necessary. The risk assessment must cover the work on or near
the specific equipment and it must be carried out by someone with comprehensive
knowledge and experience of the type of work and the means of controlling the
risks.
A risk assessment is about identifying and taking sensible and proportionate
measures to control the risks in your workplace, not about creating huge amounts
of paperwork. Ask your employees what they think the hazards are, as they may
notice things that are not obvious to you and may have some good ideas on how
to control the risks.
As part of this process, you will need to consider the competence of the people
who will be carrying out the work and their ability to avoid danger, taking into
account the available precautions.
Having identified the hazards arising from the live work, you then have to decide
how likely it is that harm will occur and the severity of injury that might occur. Risk
is a part of everyday life and you are not expected to eliminate all risks but you
need to take account of the fact that electricity can cause very serious injuries and
death. What you must do is make sure you know about the main risks and the
things you need to do to manage them responsibly. Generally, you need to do
everything reasonably practicable to protect people from harm.
Decide Whether It Is Reasonable To Work Live
The risk assessment should inform managers and supervisors whether it is
reasonable in all the circumstances to work live. The decision should not be taken
lightly. At this stage the economic and operational factors should be evaluated
against the risks involved before making a decision, bearing in mind that the risks
associated with working live can be very serious. Minor inconveniences arising from
working with the equipment dead, sometimes arising from commercial and time
pressures, will very rarely outweigh the risks associated with live work.
Decide Whether Suitable Precautions Can Be Taken To Prevent Injury
Providing the requirements above have been met, live working can still only be
justified if suitable precautions are taken to prevent injury arising from the hazards
identified in the risk assessment. The precautions should have been identified in the
risk assessment and might include.
■ Installing temporary insulation, protective enclosures, or screens to prevent
parts at different potentials being touched at the same time;
■ Using temporary barriers with warning notices affixed to keep unauthorised
people away from the work area;
■ Ensuring that adequate clearances are established and maintained when
working near to live equipment (see Appendix 3 of the Memorandum and
Section 729 of BS 7671:2008 (+A1:2011) for information on clearances). For
work near live overhead power lines, see GS6 Avoiding danger from overhead
power lines.
Plan The Work
Many electrical accidents are due to a failure to plan ahead. Planning should
consider the management, supervision, implementation, and completion of the
work, and should lead to a formal system of work based on information in the
safety rules and a task-specific risk assessment. In some instances, the planning
requirements of the Construction (Design and Management) Regulations19 will
apply. You should consider the following:
■ The work to be done;
■ The hazards of the system or equipment to be worked on and the risks
associated with the work;
■ The people doing the work, their competence, and the level of supervision
necessary;
■ The precautions to be taken and the system of work to be employed;
■ The possibility that the nature of the work may change, eg a testing job may
turn into fault finding.
There must be adequate information available about the electrical system and
the work to be done. In the case of a newly constructed electrical system (or newly
installed equipment), there should be drawings and schedules relating to the design
and these should have been updated, if necessary, by the people carrying out the
installation.
Select & Instruct Competent Workers
Training as part of making a person competent is very important. Even the
most highly qualified and capable people may not be competent to carry out
specific types of work without suitable training. Competent workers will be selfdisciplined
and aware that reckless behaviour with electricity can lead to injury and
death.
Those in control of the work should:
■ Assess the degree of competence of individual workers against the specific type
of work to be done;
■ Provide clear instructions, information, and adequate training for employees on:
the risks they may face;
The measures in place to control the risks, emphasizing the safe system of
work to be used;
How to follow emergency procedures;
■ Arrange for those being trained or those newly trained to be accompanied and
supervised.
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