Electrical Testing Intervals for all types of Premises.
We are often asked how often particular properties need to be tested, it can be unclear for customers and clients alike.
Below is a concise breakdown of what you need to know for your particular type of property
The frequency of periodic inspection and testing must be determined taking into account:
- the type of installation
- its use and operation
- the frequency and quality of maintenance
- the external influences to which it is subjected
The table below provides guidance on the frequency of formal inspections of electrical installations as well as routine checks.
|Type of Installation||Routine check||Maximum period between
inspections and testing
(see notes below)
|Domestic accommodation –
Domestic accmomdation –
rented houses and flats
|change of occupancy/10 years
change of occupancy/5 years
1, 2, 10
|Commercial||1 year||change of occupancy/5 years||1, 2, 3, 4|
|Educational establishments||6 months||5 years||1, 2, 6|
|Hospitals and medical clinics –
Hospitals and medical clinics –
|Industrial||1 year||3 years||1, 2|
|Residential accommodation (Houses of
Multiple Occupation) – halls of residence,
nurses accommodation, etc.
|1 year||Change of occupancy/5 years||1, 2, 10, 11|
|Offices||1 year||5 years||1, 2|
|Shops||1 year||5 years||1, 2|
|Laboratories||1 year||5 years||1, 2|
|Buildings open to the public|
|Cinemas||1 year||1-3 years||2, 6|
|Church installations||1 year||5 years||2|
(excluding swimming pools)
|1 year||3 years||1, 2, 6|
|Places of public entertainment||1 year||3 years||1, 2, 6|
|Restaurants and hotels||1 year||5 years||1, 2, 6|
|Theatres||1 year||3 years||2, 6, 7|
|Public houses||1 year||5 years||1, 2, 6|
|Village halls/Community centres||1 year||5 years||1, 2|
|Special and specific installations
(for medical locations see above)
|Agricultural and horticultural||1 year||3 years||1, 2|
|Swimming pools||4 months||1 year||1, 2, 6|
1, 2, 6
|Highway power supplies||as convenient||6-8 years|
|Marinas||4 months||1 year||1, 2|
|Fish farms||4 months||1 year||1, 2|
|Emergency lighting||daily/monthly||3 years||2, 3, 4|
|Fire alarms||daily/weekly||1 year||2, 4, 5|
|Launderettes||monthly||1 year||1, 2, 6|
|Petrol filling stations||1 year||1 year||1, 2, 6|
|Construction site installations||3 months||3 months||1, 2|
- Particular attention must be taken to comply with S1 2002 No 2665 – Electricity Safety, Quality and Continuity Regulations 2002 (as amended).
- Electricity at Work Regulations 1989, Regulation 4 and Memorandum of guidance (HSR25) published by the HSE.
- BS 5266-1:2011 Emergency lighting. Code of practice for the emergency escape lighting of premises
- Other intervals are recommended for testing operation of batteries and generators.
- BS 5839-1:2013 Fire detection and fire alarm systems for buildings. Code of practice for design, installation, commissioning and maintenance of systems non-domestic premises
- Local Authority Conditions of Licence.
- It is recommended that a caravan is inspected and tested every three years, reduced to every year if it is used frequently (see Regulation 721.514.1 and Fig 721 – Instructions for electricity supply).
- The person carrying out subsequent inspections may recommend that the interval between future inspections be increased or decreased as a result of the findings of their inspection.
- Medical locations shall have their isolating transformer equipment inspected and tested for functionality as well as alarms etc.; every third year the output leakage current of the IT isolating equipment shall be measured.
- The Landlord & Tenant Act 1985 requires that properties under the Act have their services maintained. Periodic inspection and testing is the IET recognised method of demonstrating this.
- The Management of Houses in Multiple Occupation (England) Regulations and the Management of Houses in Multiple Occupation (Wales) Regulations