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What is a PAT Test

Portable Appliance Testing is usually recognized as “PAT”. So what is a PAT Test? PAT Testing is the term used to explain the testing of electrical equipment used to demonstrate that they are safe to use.

The official term for this process is “in-service inspection & testing of electrical equipment”. Mainly electrical safety defects can be detected by visual inspection, but some types of defects can only be detected by the test. However, it is important to understand that visual examination is an integral part of this process because defects in certain types of electrical safety cannot be detected by simply examining them. At the end of the PAT test, each item must be marked as ‘Pass’ or ‘Fail’. In addition the results should be recorded.

It is rumored that all portable electronic devices need to be tested every year in a low-risk environment. However the law generally requires employers to ensure that electrical equipment is maintained to avoid hazards. Therefore the time spans for testing different appliances differ. Furthermore it differs depending on the facility it is in

The PAT test instrument uses specific PAT testers to provide in-depth testing of the electrical condition of the equipment. It involves testing quantities which include: Earth’s continuity; Lead Polarity Insulation resistance, etc.

The PAT test is for portable appliances. It usually includes the following

Seven types of electrical appliances.

  • Fixed appliances
  • Stationary appliances
  • IT appliances
  • Moveable appliances
  • Portable appliances
  • Cables and chargers
  • Hand-Held appliances

The law for PAT testing varies from country to country. In the UK, for example, there is no legal obligation, but there is a legal obligation to keep electrical equipment safe. The same is true in some other countries.

Which Portable Appliances should be tested?

In present legislation, there is no exact definition of what “portable devices” are. However, the general interpretation is any device with a plug that can be inserted into a common wall socket. High-risk machinery that requires inspection by an authorized electrician is not tested during the PAT test. Portable does not necessarily mean “moving”. PAT testing applies to fixed devices, stationary appliances, IT appliances, portable appliances, cables, chargers, and handheld devices. Here are two key factors that determine whether an item should be tested. These are the electrical ‘class’ and the ‘category’ of the item.

Electrical classes in PAT testing

Electrical appliances are mainly classified as Class 1, 2, or 3, Class 1 is the most dangerous, and Class 3 is the least dangerous than the other classes. The class of an instrument helps determine if it needs a PAT test and to what degree. Class 1 devices require a full PAT test, Class 2 devices require a PAT insulation test, and Class 3 devices do not require a PAT test.

Class 1

With Class 1 appliances, the user is protected by providing a combination of basic insulation and earth connectivity. Thus providing two levels of protection. When PAT testing Class 1 instruments, ground continuity, and insulation resistance tests are performed. Therefore the bottom line is that

  • If it is made of metal, it must be a Class 1 appliance
  • Additionally If it has three basic cables, it be a have a Class 1 appliance
  • Furthermore If the plug has a metal fit, it must be a Class 1 appliance

Class 2

In Class 2 devices, the user is protected by at least two layers of insulation. For this reason, Class 2 devices are also called double insulated. They do not need an earth connection when PAT testing Class 2 devices. Thus only an insulation resistance test is taken. In summary:

  • If it’s plastic, it must be a Class 2 appliance
  • Furthermore If the rating plate has a double box symbol, it must be a Class 2 appliance

Class 3

Appliances running on SELV (separately extra-low voltage) are considered class 3. This means that the device cannot produce enough voltage to put the user at risk of electric shock. Usually, the power output of these objects is 50vac or 120vdc. Class 3 products do not require PAT testing but their charging leads might be Class 2 so PAT testing is required.

How often should PAT tests be conducted?

We use office equipment as our default terminology because it’s easy and everyone understands what that means. Office equipment consists of computers, printers, copiers, and other devices in the office. Items such as lamps and radios.

Therefore as a general rule, we recommend having this test every 2 years. Furthermore test it initially, inspect it after 2 years, then test it again after 2 years. If you treat it as a low-risk device, then the additional low-risk would be appliances that are even less mobile. However these could cause damage to fixed devices. Devices such as integrated kitchen appliances, and server systems.

However even though this is less likely, as long as you know they were installed correctly, and have not been restored, then they will be fine for a year or two.

A different scenario is with office equipment in education facilities. Thus there may be a slightly higher risk of office equipment used by students in a  school because they potentially less likely to take care of the equipment.

Also consider items that are mostly portable kitchen appliances. Items such as hand-held items in the cafe. An example would be accessories such as living aids, etc. that may need to be examined annually. High-risk equipment may include electrical tools in the factory that needs to be tested more often. But before we propose their frequency, we will consider the risks to the site, which can be 12 months or less.

The HSE Website clarify the regulations with regards to PAT Testing further here

Advantages of PAT

There are many benefits to testing your equipment, the biggest of which is ‘saving lives’. However, the biggest advantage of PAT testing for most workplaces is that you keep your electrical equipment safe. Therefore while working you have your responsibilities for workplace health and safety.

About 15% of home fires in the UK and Wales are caused by electrical faults. Primarily with electrical equipment malfunctions and broken cables being the main causes. On average, the UK alone sees around 8,000 electric fires a year. Furthermore 4,000 injured and more than 30 deaths.

  1. You can significantly reduce the risk of electrical accidents, including electrical accidents and fires, by performing regular PAT testing. You can never guarantee that there will be no accidents at work. However PAT testing will dramatically reduce these problems and save your employee from potentially fatal harm.
  2. A regular PAT test will help you comply with many safety regulations in the UK, including the Electricity Work Regulation (EAW) and the Health and Safety of Work Act.
  3. While maintaining the safety of your employees should be your top priority, you would also like to make sure that your business is complying with rules and regulations. Furthermore those that could lead to legal action if you do not comply.
  4. Another benefit is the practice of detecting electrical equipment malfunctions in the workplace. This improves performance as well as safety in the workplace



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