Fixed wiring in-service electrical inspections, why they are necessary and how they can
benefit your business.
Helping you to understand your responsibilities
Electrical Test Midlands – sharing technical expertise
It’s a near certainty that your business uses electrical power in
some way. Therefore, in order to manage risks and comply with
the law, your fixed wiring needs to be inspected regularly. Meeting
this requirement effectively, and ensuring that the benefits
outweigh the costs, requires you to be familiar with the concept of
fixed wiring inspection, and to know what approach to take.
Bear in mind, according to the HSE’s website (www.hse.gov.uk/
electricity), about 1,000 people per year have an electrical
accident and about 25 of those are fatal.
The independent safety inspection industry tends to categorise
electrical equipment and systems as follows:
- PAT – Portable Appliance Testing – for items like kettles.
- Plant – for items such as motors, welding equipment, fans and
air conditioning units
- Fixed wiring – all the equipment required to distribute electrical
power safely from the origin to all the plant, equipment and
appliances at the relevant site. Fixed wiring includes conductors
(e.g. cables and cords), connections (e.g. distribution boards),
switching devices, protective devices (e.g. fuses, circuit breakers
and residual current devices – RCDs), enclosures and, where
applicable, fire barriers.
Fixed wiring’s broad definition means that its inspection can
encompass little or much. At its simplest, the inspection is a
non-intrusive visual check of accessible components such as
distribution boards, sockets, cables, cords and light fittings.
At its most thorough, it could comprise the following:
? An appraisal of the job, featuring:
- Job-specific risk assessment
- Survey and testing of the installation’s earthing,
continuity, insulation, polarity, layout and
- Enquiries to determine the degree to which parts
of the system can be isolated
- Review of available documentation
? Visual check of all accessible components
? Labelling, i.e. unique identification of circuits
? Functional tests to check whether all the relevant
components do what they are supposed to do
? Thermographic testing to quickly detect hidden defects as
‘hot-spots’ in the system
? Clear reporting – publishing circuit diagrams, all test
results and a summary of any defects with actions
recommended to make safe.
Electrical Test Midlands sharing technical expertise
A balance always has to be struck between inspection and
maintenance. Too little inspection/repair, and the risk will be too
great; too much inspection/repair and the cost will be too great.
Of course, the more preventative your maintenance, the lower
the reliance on in-service inspection and repair to control risks
in the first place. You will need to strike a balance between
inspection and maintenance (repair) activities that you are
Another important consideration is whether you use the same
inspectors for maintenance or perform maintenance independently.
You will also need to choose whether to subcontract or go
in-house, the depth and frequency of the inspection (and
maintenance); and the degree of detail in the inspection reports.
You may simply wish to add electrical inspection to whatever
in-service inspection arrangements you have for other items,
such as your lifting equipment.
Deciding on the depth and frequency of inspection, and the
detail of reports, may be more difficult. The decision needs to be
based on a potentially complex interaction between inspection
activities, maintenance activities, production requirements, and
In our view: if you are not already doing so, you should make use
of risk-based inspection (RBI) techniques to determine the approach
that you take for the in-service inspection and maintenance of your
You should not be too daunted by the thought of applying RBI. The
rigour applied to the RBI assessment should be commensurate with
the scale of the electrical risk at your premises and it might not take
too much effort to complete.
Generally, the benefits of RBI outweigh the cost. RBI delivers a
specification for an inspection and maintenance regime that is
suitable and sufficient and optimises the risk-control-per-unit cost.
A suite of test methods and required outcomes are specified in
detail in the British Standard BS 7671: 2008, often referred to as
the IEE Wiring Regulations. In fact, the requirements of this
standard are not regulations in the legal sense.
The frequency and scope of your in-service fixed wiring
inspections should always be determined by an assessment
of the risks.
BS 7671: 2008 does provide guidance on both frequency and scope
of inspection for low voltage installations (less than 1,000V a.c.
or 1,500V d.c.), based on criteria like the type of premises:
e.g. ‘Three-yearly for a factory and five-yearly for offices.’
Note: this British Standard does not cover the public electricity
supply, electricity on vehicles, nor fixed wiring in quarries, mines
and other hazardous areas (where there is an explosion risk).
Electrical test midlands – sharing technical expertise
Repairs and conflict of interest
Regarding repairs, the in-service inspection contractor may be
prohibited from undertaking repairs. For example, Etm is a electrical compliance company.
The risks and benefits
A few mA of electrical current can be fatal and the
mains voltage (230V a.c.) should always be considered
The principal hazard associated with fixed wiring is electric shock.
However, other hazards should be considered, including burns,
arcing (which can damage the eyes) and ignition – setting fires or
creating explosions if flammable/explosive materials are present.
What is at stake, of course, is the health and safety of people and
significant financial and business losses. So the benefits are clear:
control the risk to control the cost.
The law says that all employers must safeguard the health and
safety of all people affected by their undertaking and, in the UK,
it is a criminal offence to fail in this duty of care.
Fundamentally, employers are required to assess the risks associated
with their business and manage those risks at a tolerably low level.
More specifically, employers are required to comply with applicable
regulations; often a large number of them.
For fixed wiring, the specific regulations are the Electricity at Work
Regulations, 1989 (EAW). The HSE has issued a very useful
document, which is freely available to download from their
website, entitled ‘Memorandum of Guidance on the Electricity
at Work Regulations, 1989.’
You will note that this guidance is non-prescriptive,
in keeping with the goal-setting format of the
regulations, which means that maintenance is a
statutory requirement, but the scope and frequency
of maintenance and inspection should be risk-based:
i.e. suitable and sufficient.
In spelling-out the requirements of the EAW regulations, the
HSE guidance makes it clear that fixed wiring shall be maintained
so as to prevent danger (so far as is reasonably practicable) and
that regular in-service inspection is an ‘essential’ part of
For prescription, you can turn to the British Standard mentioned
above (BS 7671: 2008). Remember: This British Standard is
comprised of non-statutory regulations.
For more information
Should you require any further guidance, please contact:
(Etm) Electrical Test Midlands on 01922 710014