Last updated: 04.11.21

How Often Should you PAT Test?

PAT testing is a very important part of the maintenance of electrical items. Even appliances like kettles can pose massive health and safety risks if they malfunction, and failing to carry out the proper assessments could put you and the people around you at risk.

Although there is no official legislation outlining how often you should PAT test appliances, there is a lot of trusted guidance that can be very helpful if you are a qualified PAT tester or responsible for maintaining electrical equipment. This article includes all the information you need on what needs to be PAT tested and suggested PAT testing frequency, as well as outlining what these safety checks involve.

What is a PAT Test?

‘PAT’ stands for portable electronic appliance. A PAT test evaluates whether one of these appliances is safe to use and ensures that any faulty devices are quickly identified and fixed or disposed of before they can cause any harm.

PAT testing is a very important part of electrical health and safety because it reduces the likelihood of accidents caused by faulting electrical appliances, such as burns or electric shocks. It also protects wider electrical systems by reducing the likelihood that an appliance will trip or fuse a series of electrical circuits and potentially damage other items as well.

A regular PAT test is required of any piece of electrical equipment that is not part of a fixed installation. If a device or appliance needs to be connected to a fixed installation or generator to work, it probably qualifies for a PAT test.

How Often is PAT Testing Required?

There is currently no legal guidance on how often PAT testing needs to be carried out. In fact, the only piece of legislation that affects PAT testing is The Electricity at Work Regulations (1989), which just say that electrical equipment needs to be maintained and kept safe for use, which PAT testing can be a part of.

However, you should not neglect PAT testing electrical appliances, especially if they are known for being dangerous or could cause serious harm to someone if they malfunctioned. There is unofficial guidance for how frequently different kinds of electrical items should be tested, which we will outline below.

First of all, it is important to understand the different kinds of electrical appliances and their classifications, as this can affect how often they should be tested. There are three different equipment classifications within PAT testing requirements, which are:

    • Class I: Earthed Appliance. An appliance where the user is protected by a level of insulation and an earth connection. Usually made of metal with a plug that has a metal Earth pin and a three-core cable. Class I appliances are most commonly found in people’s homes, including things like microwaves, toasters and fridges.
  • Class II: Double Insulated Appliance. An appliance that has two layers of insulation to protect the user and does not have an earth connection. Most Class II appliances can be identified by a double insulated symbol somewhere on their plastic casing. Examples of this classification of appliances include plastic power tools and devices like computers.
  • Class III: Separated Extra Low Voltage. An appliance that has power supplied by a low voltage provider, usually working at under 50 V. They can be identified by their Separated Extra-Low Voltage transformer and two symbols on their casing which shows their class and transformer.

As well as the class of an appliance, several other factors should be considered when deciding how often you should PAT test appliances. Think about:

  • How often the appliance is used. If it is used multiple times a day by different people, it is probably going to require a PAT test much sooner than an item that is only occasionally turned on
  • How often the appliance is moved. This is particularly important with larger or more complex appliances, as transporting them could cause damage that may lead to electrical faults. If an appliance is frequently in transit or is likely to get knocked about, it may need more frequent checks
  • The tasks the appliance is used for. If it is an electrical item like a microwave that isn’t moved and just switches on and off then the likelihood of faults caused by use is low, whereas handheld tools used for manual tasks will probably wear out or get damaged a lot sooner
  • How the user interacts with the appliance. Handheld appliances have a greater potential to cause harm, as the user is in direct contact with them and more likely to receive a direct injury if something goes wrong, whereas stationary ones pose less of a risk. If an appliance is handled a lot and moved around by the user, it should be tested more frequently
  • Whether the appliance has a history of faults. If you know that a particular item commonly starts to break or malfunction after a certain amount of use, or just generally has a certain shelflife, this may impact how frequently you PAT test it
  • The environment the appliance is used in. Household appliances are very unlikely to get damaged by their environment, whilst those used in industrial or construction workplaces may get damaged and therefore will require a greater frequency of PAT testing

The suggested guidelines for how often you should PAT test different portable appliances are as follows.

Office Technology

Office appliances like desktop computers and fax machines are some of the most low-risk portable devices, meaning that they don’t need to be PAT tested very often. The recommendation is to complete a ​​formal visual inspection every 2–4 years, and an official PAT test every 5 years if the appliance is not double insulated.

Class I Appliances

Class I appliances are earthed, which refers to the way the conductor is connected. Kettles are one of the most common examples of a Class I appliance, which are advised to be tested every 1-2 years and have formal visual inspections every year.

Cables and Plugs for Class I Appliances

The cables and/or plugs connected to Class I appliances also need to be PAT tested, although not at a very frequent rate. The frequency will depend on the kind of appliance they are attached to, but generally, PAT testing is recommended every 1-4 years.

Class II Appliances (rarely moved)

Class II appliances that are rarely moved, such as fans or table lamps, are recommended to be PAT tested every ​​2–4 years. These kinds of double-insulated appliances do not usually need an official combined inspection and test, just a formal visual inspection.

Class II Appliances (handheld)

Class II appliances that are handheld and moved around a lot, such as kitchen equipment like a blender or electric whisk, are recommended to have a formal visual inspection every 6 months to a year, depending on the frequency that it is used.

110V Construction Appliances

110V construction equipment is recommended to have user checks carried out every week as part of general safety assessments, a formal visual inspection every month and an official PAT test and inspection every 3 months. 

230V Construction Appliances

230V construction appliances are recommended to have user checks carried out every day or every shift as part of general safety assessments, a formal visual inspection every week and an official PAT test and inspection every month. 

Heavy Industrial Appliances

Heavy industrial appliances that are not used in construction have slightly different guidelines. They are recommended to have user checks carried out every day, a formal visual inspection every week and an official PAT test and inspection every 6-12 months depending on how often they are used. 

Light Industrial Appliances

Light industrial appliances need less frequent checking, although basic user checks before use are still advised. A formal visual inspection is recommended every 6 months and an official PAT test and inspection is recommended every 6-12 months.

How Long Does a PAT Test Last?

There is no official measure of time that a PAT test is valid for. Instead, a PAT test lasts until the appliance becomes unsafe to use, in which case another PAT test is required to see if the problem can be resolved or if the appliance needs to be replaced. Sometimes a risk assessment may include guidance on how often devices should be tested, particularly in schools or workplaces where general health and safety is the responsibility of an employer. 

You should follow the guidelines on how often to conduct a PAT test for all appliances, as this will ensure that you are re-testing the safety of items before they are likely to have developed faults or become unsafe.

What Does a PAT Test Involve?

There are three different stages of a PAT test; a user check, a formal visual inspection, and a combined inspection and test. Whilst almost anyone can carry out a sufficient user check on a portable appliance, the other two stages need a greater understanding of electrical systems and faults, which is why it is important to get a proper PAT tester to complete these safety assessments.

User Check

A user check involves inspecting the wire, plug and external casing of an electrical appliance before you use it. This makes sure that there are no obvious faults in the device, such as tears or splits in the wiring, cracks in the casing or signs of burning.

Whilst you mostly need to rely on common sense when it comes to doing a user check, it can be beneficial to have an understanding of what common faults to look out for, such as obvious damage to the plug or the wiring, overheating, or a delay in function when the appliance is switched on.

Visual Inspection

An official visual inspection is the next requirement of a PAT test, which does need some formal training in order to be properly completed. It involves a thorough check of the external parts of an appliance as well as taking the device apart and checking its internal workings for any signs of faults or damage.

PAT testers are required to read appliance manuals during this stage of the test to compare the official internal diagrams with what the internal wiring actually looks like, to spot any obvious faults. This could include terminals connected to the wrong wires, loose screws, or fuses in the wrong place.

Combined Inspection and Test

The final stage of PAT testing requires PAT test equipment to assess the parts of an appliance that cannot be visually checked, such as its insulation and internal integrity. This is done using specialist equipment and can only be carried out by someone who has an official PAT test qualification.

The number of tests and the equipment required will depend on the types and size of the appliance that is being checked, as they have the potential to be more dangerous than others and therefore need more thorough safety checks. These may include earth bond tests, earth leakage tests and insulation tests.


How often should you PAT test a microwave?

A microwave is an appliance that almost everyone has in their homes, and so is one of the most common examples of an electrical item that needs to be PAT tested. It falls into the Class 1 category of appliances which means that it should be PAT tested every 4 years, unless it is used in a school in which case the official guidance is to complete a test every year.

Does new equipment need PAT testing?

New electrical appliances should be in perfect working condition when they are purchased, so in theory no new equipment should require PAT testing before it is used. However, sometimes items can get damaged in transit or may have been assembled incorrectly, which is why you should always carry out a basic user check before plugging anything in so you can spot any obvious faults.

How many items can you PAT test in a day?

There is no limit on how many items can be PAT tested in the day, so the number of appliances that get checked really depends on the speed of the tester and how confident they are in their role. It is important never to rush a safety check like a PAT test however, as this could lead to missing a fault that could cause problems later down the line.


PAT testing is an important part of health and safety both at home and in the workplace. Whether you’re wondering how often you need to get your kitchen appliances looked at, or you are responsible for the health and safety of staff working with portable appliances, understanding the considerations and recommendations involved with the frequency of PAT testing will ensure that the devices and equipment you use stays safe.

If you’d like to find out more about the legislation and guidance connected with PAT testing, we offer a ‘How to Carry Out Portable Appliance Testing’ online course which is suitable for anyone who wants to become a PAT tester or is responsible for the electrical appliances in their home or workplace.