Fixed Wiring Testing

The 5 year electrical testing rule applies to commercial, office, retail and educational properties. But other types of environments are recommended to have more regular testing, so it’s important to check which maximum interval applies to the particular type of building.

Fixed wire testing involves testing and inspecting the electrical systems and installations within a building.

Following testing, you will be issued an EICR, certifying the condition of the entire electrical system within your premises, including electrical wiring, circuits, accessories and connections.

Regular testing of a building’s wiring structure and maintenance is mandatory by law under The Electricity at Work Regulations 1989 and IET Wiring Regulations BS 7671:2008.

The frequency of testing required for compliance varies between environments, determined by a number of factors such as the use, operation and other external influences affecting the installation.

The IET Wiring Regs provide guidance on the maximum interval between fixed wire tests, based on the type of premises.

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Guidance on frequency of periodic, fixed wire testing and routine checks of electrical systems and installations (IET Wiring Regs, BS7671, 2018):


Type of installation Routine check Maximum interval between
General Installation
Domestic accommodation –
Domestic accmomdation –
rented houses and flats

1 year

Change of occupancy/10 years
Change of occupancy/5 years
Residential accommodation (Houses of
Multiple Occupation) – halls of residence,
nurses accommodation, etc.
1 year Change of occupancy/5 years
Educational establishments 6 months 5 years
Industrial 1 year 3 years
Commercial 1 year Change of occupancy/5 years
Offices 1 year 5 years
Shops 1 year 5 years
Laboratories 1 year 5 years
Hospitals and Clinics
Hospitals and medical clinics –
general areas
Hospitals and medical clinics –
medical locations
1 year

6 months

5 years

1 year

Buildings open to the public
Cinemas 1 year 1-3 years
Church installations 1 year 5 years
Leisure complexes
(excluding swimming pools)
1 year 3 years
Places of public entertainment 1 year 3 years
Restaurants and hotels 1 year 5 years
Theatres 1 year 3 years
Public houses 1 year 5 years
Village halls/Community centres 1 year 5 years
Special and specific installations
(for medical locations see above)
Agricultural and horticultural 1 year 3 years
Swimming pools 4 months 1 year
Caravan parks
1 year
6 months
3 years
1 year
Highway power supplies As convenient 6-8 years
Marinas 4 months 1 year
Fish farms 4 months 1 year
Emergency lighting Daily/monthly 3 years
Fire alarms Daily/weekly 1 year
Launderettes Monthly 1 year
Petrol filling stations 1 year 1 year
Construction site installations 3 months 3 months

Fixed wire testing frequency: Practical considerations

In practical terms, the guidance acts as the starting point to devise a testing programme that ensure compliance within operational and commercial demands of the premises.

For example, larger buildings may be broken down into sections with testing for each run to a different schedule to ensure safety, minimise operational disruption and manage costs. And since testing requires parts of the system to be temporarily isolated, it usually takes place out of hours, which may only be achievable across the full system over an extended period of time.

Specialist use environments will also require specialist testing strategies, for example, spas, factories and clinical environments.

This means using the IET guidelines as a framework against which to create a testing schedule which makes commercial and financial sense while satisfying health and safety compliance and the specialist needs of the environment in question.


What is a ‘routine check’?

Routine checks are used between formal fixed wire tests to ensure continued safe performance of electrical installations. This usually involves a visual inspection and checking the operation of the equipment and switchgear to identify potential issues such as wear & tear, general deterioration and loose or missing parts.

Why are fixed wire tests needed?

Fixed wire testing checks the condition of the electrics against the UK standard for the safety of electrical installations, BS 7671. Each circuit’s cable and accessories is inspected for visual damage and wear and tear, followed by a series of tests to verify the wiring is safe and the circuit is wired correctly.

Fixed wire testing is a legal requirement for any organisation to ensure compliance with legal requirements to ensure the building’s electrical system is safe, maintained and tested by competent, qualified individuals. In doing so you are ensuring the provision of a safe and hazard-free environment for employees, visitors and the public at large.

Electrical installations deteriorate with age and use. Regular testing and inspections will identify potential or existing electrical faults or hazards to be remedied.

Fixed wire testing is also usually mandatory for insurance purposes.

Fixed wire testing should be performed by competent persons – generally this would mean a qualified electrical engineer.

Following the electrical testing and inspection, you will be issued an Electrical Condition Report (EICR) for the fixed wire test.

A satisfactory EICR issued by a competent and qualified individual confirms compliance with the Health and Safety at Work Act 1974 and the Electricity at Work Regulations 1989.


Do you need help with 5 Year Electrical Testing Fixed Wire Test?

Tennals are highly experienced in conducting fixed wire tests and inspections in environments as varied as large-scale industrial, hotel chains, schools, retail outlets and leisure and entertainment centres and residential properties.

We can help with your electrical and fixed wire testing needs, carrying out the full testing and inspection requirement and advising on your maintenance programme to ensure compliance with the law. We can also provide a quote to carry out any remedial work identified during testing to bring the installation to standard.

For help and advice with your Fixed Wiring Testing Tennals’ team of specialist electrical engineers.