Photograph of me checking over a plug.

What is PAT Testing?

The inspection and testing of electrical equipment, or 'PAT Testing', as it is usually called, is the procedure whereby electrical equipment is formally visually-inspected and instrument-tested for electrical safety. PAT testing is mostly carried out either in the workplace, rented accommodation or in residential care homes, etc. Also, some venues such as concert halls and market stalls are now insisting on seeing evidence of PAT Testing of the electrical equipment used by the performers or those that are renting the stall.

PAT testing is short for 'Portable Appliance Testing', which is unfortunate really because this suggests that the inspection and testing procedures only apply to truly portable equipment: this is not the case. With PAT Testing, virtually all items of electrical equipment (230 and 110 volt) are formally inspected and tested: portable, movable, hand-held, stationary, fixed and built-in. Furthermore, the word 'testing' implies that the equipment is only checked over with test instruments. However, this too isn't the case, for the procedure also involves the important use of formal visual inspection. In fact, many of the items that I personally work on fail as the result of close, visual inspection: plugs with gaping holes, bare copper wires, free-standing electric fires with one foot either missing or hanging off, plugs with cigarette paper acting as a fuse (yes, really!), burnt-out and melted extension lead sockets, etc.

PAT Testing in the workplace, rented accommodation or in residential care homes etc., whilst not a legal requirement in itself (see 'Do we have to have PAT Testing done?'), is usually carried out on an annual basis (see 'How often should Testing be done?') to determine whether the electrical equipment in use there is, in simple terms, 'safe, well-maintained and suitable for the purpose for which it is being used', which certainly is a legal requirement. NB. In the case of electrical equipment in rented accommodation or residential care homes, the scope of the legislation only covers equipment that has been supplied by the landlord or care-home company (the 'supplier'); it is not concerned with personal equipment owned by tenants or residents. For much more detailed information about the legislation concerning electrical equipment in the workplace, rented accommodation or residential care homes, etc., see (see 'Do we have to have Testing done?').

Practical Limitations

In a standard workplace, I potentially test all 230 volt mains-powered items that have a standard three-pin plug attached. In an industrial setting, I can additionally test 16A and 32A, 110 volt (yellow connectors) and 230 volt (blue connectors) equipment such as site tools, extension cables, extension reels and 230v-110v step-down transformers. In rented property, I normally only test the items (with plugs) that are supplied by the landlord. Similarly, in residential care homes, etc., unless directed otherwise, I normally only test the items (with plugs) that are supplied by the care-home owner either for use by the residents or by the staff. This is because personal equipment owned by tenants or residents is not covered by legislation, and is therefore not tested.

Systems such as file servers, mail servers and network switches/hubs etc. will not be inspected/tested by me without the express permission of the client, as this would normally require the shutting down of this equipment.*

I do not unplug and test telephony equipment such as PABX or ISDN boxes, etc. that are supplied by the telephone company (much of this equipment, once installed, should really never be unplugged or switched off).*

Equipment such as video recorders, clocks, central heating system timers, burglar alarms, etc. that loose their programmed memory when disconnected from mains voltage, will (for this reason) only be unplugged and inspected/tested by me with the express permission of the client, and it is the responsibility of the client to arrange for reprogramming of this equipment, if necessary.*

Please make sure that the equipment that you want inspected/tested is on site when I arrive! This is particularly pertinent in the case of laptop computer chargers, projectors, power tools, mobile phone chargers, etc. NB. In the case of equipment that is either powered or charged by a power supply adapter/charger, such as laptop computers, battery hand-held power tools, mobile phones, tablets, digital cameras, etc., you only need to supply me with the power supply adapter/charger; I don't need access to the actual equipment itself.

The equipment can only be tested if I have easy access to its plug. If the plug is inaccessible, for example, hidden behind heavy, awkward objects, then unfortunately the equipment will not be instrument-tested.*

I can only test items that have a standard 230 volt three-pin plug attached (or 16A/32A yellow or blue industrial site connectors); electric cookers, water heaters, large built-in radiators, electric heaters, etc. that are directly wired into a fused outlet will not be tested as this would require switching the electricity off at the main consumer unit (something which would inconvenience everyone) and also the dismantling of the fused outlet, something which, like most PAT Testers, I am not qualified, insured or legally allowed to do.*


* Having said this however, I may be able to carry out the important 'earth continuity' test on some of this equipment even when it is switched on and running, providing that there is a spare electric three-pin wall or extension lead socket very close by.


“As may be necessary to prevent danger, all systems shall be maintained so as to prevent, so far as is reasonably practicable, such danger.” The Electricity at Work Regulations 1989

“It shall be the duty of every employer to ensure, so far as is reasonably practicable, the health, safety and welfare at work of all his employees.” The Health and Safety at Work etc. Act 1974

“Dear Bob, Many thanks for all your dedicated work for us and invaluable help! We will follow the guidance you have given us and appreciate your advice. Look forward to catching up next year! All our very best wishes, Lynda and Robyn.”

I am City and Guilds qualified in PAT Testing, and fully insured.


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