How to Carry out a PAT Test – A Guide to Portable Appliance Testing

Electronic appliances have a dramatic upward trend around the world in the recent past, and it will continue in the near future. All manual or traditional processes or techniques turn into modern technology via Electronic appliances. That is why our surroundings are getting congested with different devices or tools. However, electronic devices are machines of which efficiency level decreases over time. Therefore, portable appliances need to be tested by an expert to ensure safety. So, you should know first what the PAT test is? Now, time is knocking you to get a proper guide to understand how to carry out a PAT test?  Before knowing the process, you need to know the PAT test first.

Portable Appliance Testing (PAT)

Inspection or examination of electrical appliances and equipment to ensure their safety is defined as Portable appliance testing (PAT). Though safety defects in almost all electrical equipment could be found visually, few defects in appliances can be detected by testing.

PAT testing is the process where electrical appliances or equipment are frequently checked for the safety measures in the United Kingdom, the Republic of Ireland, Australia and New Zealand. PAT testing is also termed as “in-service inspection & testing of electrical equipment” formally. PAT Testing includes a visual inspection as well as cable inspection of the equipment. Check and confirmation of earthing continuity along with the test of the soundness insulation between the different parts and any type of uncovered metal parts. Visual check and testing through any skilled person required at appropriate time intervals.

Penalties if you don't meet the legal obligations

Based on the situation, the punishment for not addressing the legal requirements on electrical equipment well-being or safety, it could be two years’ imprisonment along with a limitless financial penalty.

Frequency of Testing

According to the Electricity at Work Regulations 1989, you need to check your electrical Appliance which has possibilities to cause damage or injury must be maintained in a safe condition. There is no specific instruction on what to be done or by whom or the frequency.

According to the UK Health and Safety Executive, frequency of inspection depends on the equipment type, and used environments such as a heavy machine on a construction site should be inspected more frequently than light equipment in a hotel bedroom. Record keeping or labelling can be valuable for managing and monitoring the efficiency of inspected tool and maintenance reviewing.

Simple visual checking is suggested to confirm any new equipment is not damaged. In a low-risk environment, knowledgeable staff can undertake visual inspections. Health and Safety Executive also mentions the followings into consideration as required:

  • Frequency of use
  • History of the appliances
  • Modifications effects of any repairs
  • Manufacturer’s recommendations
  • Misuse of the equipment

For inspection and testing, broad knowledge and skill are required, and the person will need to address as the followings:

  • The right equipment to do appliance tests
  • Skill to use test equipment correctly
  • Capacity to proper knowledge to the test results

Frequency of visual inspection and electrical tests is renowned by risk assessment. There are no firm test plans. This risk assessment will classify the suitability of an environment in which that equipment is being used. Factors that may impact to take the decision include:

  • Earlier records
  • Type and class of the Equipment
  • Regularity in use
  • Competence of user
  • Installation method of the equipment
  • Location of the equipment
  • Special attention needed to inspect and electrical tests to decide whether the frequency of inspection or equipment type needs to be changed

Who is Responsible for Ensuring Equipment Safety?

Current UK legislation shapes the necessary maintenance of electrical equipment in a safe condition or work environment. They also implement a legal responsibility to confirm the safety of employees as well as the public. Following people are responsible for ensuring equipment safety:
  • Equipment owners, owner of the property, company owners, directors, and line managers.
  • Operators of the appliances.
  • Maintenance managers.

According to Electricity at Work Act 1989, duty Holder must know their responsibilities, and they are accountable for ensuring the equipment safety. Duty Holder must have ensured the adequate maintenance and inspection of PAT testing and need to apply the necessary steps to ensure:

  • Analysis of the results.
  • Appropriate inspection frequencies on testing.
  • Repair the faulty equipment.
Act or legislation followed in PAT testing:
  • Health & Safety at Work Act, 1974
  • Electricity at Work Regulations, 1989
  • Provision and Use of Work Equipment Regulations, 1998
  • Management of Health & Safety at Work Regulations, 1999

What Is The Meaning of 'Electrical Classes' in PAT Testing?


 “Electrical classes” are defined as the classification of electrical equipment. Class of any material or Appliance helps to identify which one needs to be PAT tested and to what degree.</p

Electrical equipment is mainly considered for different classes such as Class 1, 2 or 3. Among them, the most dangerous equipment is classified as Class 1, and least harmful are classified as 3. devices from Class 1 need a full PAT test. In contrast, Class 2 appliances need a PAT insulation test, and no PAT test required for Class 3 devices.

Class 1 appliances: Class 1 appliances of electrical appliances have only simple insulation and rely on an earth for protection purposes.

Class 2 appliances: Among three classes, this electrical equipment class has additional insulation, and as a result, they do not rely on an earth for protection.

Class 3 appliances: These appliances are low voltage consuming items, and among these three classes, Class 3 is the safest class of electrical Appliance. Charging leads of class 3 appliances must be PAT tested.

Different categories of equipment or Appliance considered for PAT testing or visual inspections.There are some types of Appliance found for PAT testing are listed below —

  • Portable equipment
  • Handy equipment
  • Stationary equipment
  • Stable or fixed equipment
  • Information and Technology related equipment
  • Movable equipment
  • Cables and chargers of different equipment

To conduct PAT testing, a person should be skilled in followings:

  • Qualified to decide the equipment condition through visual inspection
  • Sufficient knowledge of electricity
  • Previous experience of electrical work
  • Knowledgeable on how to carry out a visual inspection
  • Skilled in PAT testing
  • Know potential hazards & precautions

Difference Between PAT Testers

  • Scratch-proof display.
  • Leakage testing for safety
  • Indication through tick or cross, pass or fail and parameter measurement.
  • 250 V insulation and surge-protected devices.
  • Test of portable electrical tools.
  • Rubber with the fitted cover.
PAT150 and PAT150R
  • Rechargeable Battery options available and surge-protected devices.
  • Substitute and mains powered leakage testing.
  • For safety testing of IT equipment, 500 V insulation testing available with 250 V insulation as well as leakage testing
  • Testing of portable electrical appliances.
  • Test of portable electrical tools.
  • Modifiable PASS test limits.
PAT410, PAT420 & PAT450
  • Extensive memory coverage.
  • Have an expert mode to boost up testing speed & secure user log-in option.
  • Dual USB ports for fast downloading.
  • Easy plugging and barcode printing.
  • Optional accessories are available.
  • The nonstop operation, no need to delay for the tester to cool down.
  • Soft keys to speed up the test.
  • Automatic asset number generation process.
  • Instant re-start.
  • A sizeable easy-to-read colour screen makes faster identifying passes and fails.
  • 25 A 10 A and 200 mA "soft" bond test, the PAT410 does 200 mA only.
  • Improved accuracy.
  • Insulation testing
  • Functional VA load test for 230 V and 110 V appliances in some models.
  • Extension and IEC lead testing including polarity, earth continuity, L-N continuity & L-N-E insulation are available.
  • Standard differential leakage test with Protective conductor or touch current leakage test
  • Substitute earth leakage test at 40 V AC.
  • Integral fuse checker.
  • Quick test process.

How to Carry out a PAT Testing

Electrical equipment in any professional or industrial location is subjected to a testing process named as Portable Appliance Testing (PAT) to check whether they are suitable to use or not. PAT testing is an efficient way to ensure electrical equipment safety.

PAT testers must have knowledge of basic electrical modes, mechanical loss to the Appliance and the kind of issues might occur in a work environment. To carry out pat testing, the first step is preparation.


PAT testers must have knowledge of basic electrical modes, mechanical loss to the Appliance and the kind of issues might occur in a work environment. To carry out pat testing, the first step is preparation.

At the very beginning, two main things are to be done before the actual testing.

Firstly, a visual inspection needs to be done to find out any major faults and the equipment, cable, and its plug etc. must be tested for any damage.

Secondly, asking about defects from the user experience.

Determining factors that will depend on the electrical type of equipment, the equipment itself and its risk measurement. Following steps are considered to carry out PAT Testing:

Safety switches test

Firstly, RCD tester is used to test the safety switches, and the tester joined the earth terminal. The half delta range protects against inconvenience. Secondly, a current applied test that is the same as the projected tripping current.

Later, after completion of testing and inspection, the tester must record a detailed report to the owner of the equipment and give some advice on further action. That full report is showing the type of equipment or appliance, name of it, location, updated situation, thorough explanation. Every machine’s PAT result and items that failed the test and causes/reasons behind it. Lastly, labelling needed to show whether the equipment or Appliance passed or failed in the PAT test along with the inspector’s signature.

Earthing continuity testing: Earthing continuity testing is a process where the equipment’s shielding is resistant to the earth circuit that does not exceed 1Ω. The tester has options to use different tests depending on his circumstance.

Resistance to insulation test: A test is performed to check the current leakage. The PAT testing is generally used to implement simple voltage to the live equipment conductors as used 230V AC is the nominal voltage. An ohmmeter can similarly be used to get the insulation resistance. After completion of the PAT test, every equipment marked as passed or failed and a record of the results should be kept for further action.

To make sure the safety of electronic equipment, you need to check your home appliances frequently through PAT Test. From the above discussion, you gathered knowledge about how frequently you should check your appliances, which skills and tools required, Act and legislation on PAT testing and so on. I believe that now you got enough information about the basic knowledge for PAT testing.

If you want to get in-depth knowledge or better understanding on PAT testing or want to be a professional PAT tester check this course.

September 4, 2020

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