The Institution of Engineering and Technology (IET), ‘Code of Practice for In-service Inspection and Testing of Electrical Equipment’ establishes three categories of inspection and testing:
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User checks: Faults are reported and logged and faulty equipment should be removed from service. No record is required if no fault is found.
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Formal visual inspections: Inspections without tests, the results of which, satisfactory or unsatisfactory, are recorded
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Combined inspections and tests: The results of which are recorded.
Inspection and testing are means of determining whether maintenance is required. Frequency of inspection and testing will depend upon the likelihood of maintenance being required and the consequences of lack of maintenance. To comply with legal requirements a robust risk assessment should be carried out in all cases, to evaluate the frequencies between inspections and testing.
User Checks
The most important check that can be carried out on a piece of equipment, particularly hand-held tools and equipment that is exempt from formal inspection and testing is a visual inspection carried out by the user, each and every time the equipment is used. User checks are limited to an external visual inspection without dismantling equipment or removing cover plates etc. User inspection, before use, should as a minimum focus on looking for:
- No signs of overheating
- No damage to the cable and/or plug
- No damage to the body of the equipment
- No signs of exposed conductors.
- Not operated in a location that could cause damage to the equipment.
- Operation of RCD (where fitted) by using the in-built test facility.
Refer to
Appendix 3 for a comprehensive check list.
Formal Inspections & Combined Inspections and Tests
All electrical inspection and testing should be performed by a person who is competent in the safe use of the test equipment and who knows how to interpret the results obtained, see Appendix 6 for training requirements.
The following steps shall be undertaken:
- Equipment being employed to undertake electrical equipment inspection and testing must be suitably maintained and calibrated according to the manufacturer’s guidelines.
- Before the equipment is tested it is subjected to a preliminary visual inspection. This visual inspection is the most important activity carried out on a piece of equipment, see
Appendix 3
- In-service testing must be preceded by a preliminary inspection as described above. Testing will involve the following:
- Earth continuity test (Class I – earthed equipment only)
- Insulation resistance test. (Class I and Class II with unearth metal)
- Protective conductor / touch current measurement (if required)
- Functional check.
- Operation of RCD (where fitted).
Special care must be taken not to damage sensitive equipment during testing. In these cases ‘soft’ earth continuity test and a reduced voltage or ‘soft’ insulation resistance test must be completed. Where possible, use labels as defined in Appendix 4, if not available a test label complying with IET code of practice may be used.
On completion of the equipment inspection and testing a durable, adhesive label of sufficient size will be fixed preferably to the lead near the plug or on the equipment to clearly indicate the date of test. All old labels must be removed from cables and equipment.
All equipment and test results will be held on an electrical appliance register held by the responsible Estate Services or departmental duty holder.
In the event of any item being found to be defective, it must be clearly marked with an adhesive red label, with a white cross and the wording “FAIL” or “FAILED”. The equipment shall be immediately withdrawn from use for repair or disposal, and the user informed of the reason for its withdrawal. See
Appendix 4
Items that are purchased or manufactured in-house must be identified, registered and inspected / tested as appropriate, BEFORE the item is used.
It is the duty of the user to ensure that these inspections or tests have been carried out prior to use.
Some equipment may be difficult to inspect and test for operational reasons. Where this is the case, special arrangements need to be made, with the responsible Estate Services, or department test operative.
The frequency of inspection and testing will be determined through a risk based assessment of each electrical item, but factors influencing the decision will include the following:
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The environment: Equipment installed in a benign environment, such as offices, will suffer less damage than equipment in an arduous environment, such as construction sites;
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The users: If the users of equipment report damage as and when it becomes evident, hazards will be avoided. Conversely, if equipment is likely to receive unreported abuse, more frequent inspection and testing is required;
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Equipment type: An appliance that is hand held is more likely to be damaged than a fixed appliance. If such an appliance is also Class 1 the risk of danger is increased because safety depends upon the continuity of the protective conductor from the plug to the appliance.
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Equipment Construction: The safety of Class I equipment is dependent upon a connection with earth of the fixed installation, where the safety of Class II equipment is not dependent upon the integrity of the electrical installation.
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Frequency of Use: Frequency of use of an appliance is important, particularly where portable, movable and hand-held appliances are concerned, because this may have implications on service life and exposure to possible damage.
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Type of Installation: Installation methods should be taken into account especially when assessing fixed equipment, because the isolator position and cable management can be an important factor of inspection and testing.
More information on inspection and testing is available through the HSE publication, INDG236, ‘Maintaining portable electrical equipment in low risk environments’.
