What is PAT Testing?

Portable Appliance Testing, also known as PAT testing, is the examination or inspection of electrical appliances and equipment that ensures they are safe to use. PAT testing ensures the appliances and equipment are safe and helps to prevent electrical accidents in the workplace. PAT testing should be done on a routine basis and clear and concise records should be documented.

Electrical equipment can become damaged, develop faults, or the parts may deteriorate. This can happen for a number of reasons and, if not identified, can have serious consequences. Using electrical appliances or equipment that is not completely safe can result in serious injuries or even death.

A PAT test checks electrical items to ensure they are safe to use. It should include both a visual examination and a more in-depth examination. The majority of electrical defects can be detected during the visual examination. However, some electrical safety defects can only be found when the appliance is tested using specialist PAT testing equipment. The in-depth testing should include earth continuity, lead polarity, and insulation resistance checks.

Once a PAT test has been completed, the PAT testing professional will be able to make a recommendation regarding the best course of action. This may include repairing the appliance or replacing all or part of the appliance.

A PAT testing specialist will be able to perform safety checks on a large variety of electrical equipment and appliances.

PAT testing is not currently a legal requirement. However, legislation in the UK states that all businesses and workplaces must maintain all electrical equipment in a safe condition. Furthermore, businesses also have a responsibility to ensure the health and safety of their employees, tenants, and the general public.

Current legislation relating to the maintenance of electrical equipment in the workplace includes:

• Health and Safety at Work etc. Act 1974.
• The Electricity at Work Regulations 1989.
• The Provision and Use of Work Equipment Regulations 1998.
• The Management of Health and Safety at Work Regulations 1999.

PAT testing is the most efficient way of ensuring that a business is adhering to legislation. Indeed, it is the most favoured electrical testing system in the UK. If legislation regarding electrical safety is not adhered to, businesses in the UK can face an unlimited fine or even imprisonment.

Testing electrical equipment can be relatively quick. Each piece of equipment will be rated with either a pass or a fail. If the equipment passes the test, it will be labelled with a safety sticker that includes information such as when the testing was completed, as well as a barcode for tracking.

Although PAT testing labels and documented records of PAT testing are not legal requirements, it is highly recommended that businesses implement these measures. It helps to ensure the effectiveness of the electrical equipment safety scheme and ensures maintenance schedules are adhered to. Establishing a clear record of equipment maintenance always demonstrates compliance with electric safety legislation.

What PAT testing prevents and detects 

An in-depth PAT test focuses on three main things:

Earth continuity

This tests the resistance of the protective earth of the electrical appliance or the cable/wire. Any accessible earthed part of the appliance and the earth pin of the plug will be tested. The earth continuity test is designed to test the connection between the earth pin and the case of the appliance.

A good connection is usually one that has a resistance of fewer than 0.1 ohms. An appliance that scores well in the earth continuity test has a vastly reduced likelihood of producing an electrical shock. To do this test, you will need a PAT testing device. Earth continuity tests are usually carried out on Class 1 electrical appliances.

Lead polarity 

Most PAT testing machines also come with a lead testing facility. You will usually first carry out a visual inspection of any leads, cables, cords, or wires. If you are satisfied that they pass the visual inspection, you will then use the PAT testing device.

The polarity test will determine whether the Live and Neutral are connected correctly to the corresponding terminals in the socket.  If they are reversed, this means the electrical appliance is live, even if it is switched off. If a fault then develops with the appliance, the likelihood of a fire developing is much greater.

Insulation resistance 

Insulation resistance tests check that there is adequate insulation between the live parts of the appliance and the parts that can be physically touched by the user. The insulation that surrounds the live parts of the appliance must have a high insulation level.

Insulation resistance tests are usually carried out on Class 1 and Class 2 electrical appliances. It is important that the individual carrying out the PAT test understands the difference in how to test insulation resistance in Class 1 compared to Class 2 appliances.

PAT testing is essential for businesses in the UK. Ensuring that electrical equipment is properly maintained can help prevent accidents in the workplace. Dorset Fire Protection stated that a quarter of all fires in the workplace are caused by faulty or incorrect use of electrics. This amounts to nearly 6,000 fires every year! This could be as a result of electrical faults or because of electrical equipment being misused.

The majority of these fires are completely preventable, and ensuring electrical equipment is maintained and is safe to use is a key way for businesses to prevent electrical fires. Not only can fires cause loss of life or serious injury, but they can also destroy equipment and premises.

According to Fire & Electrical Safety Ltd, More than 1,000 workplace accidents and 30 fatalities caused by electrical shocks and burns are reported to the Health and Safety Executive (HSE) every year in the UK. The main causes of these injuries and fatalities are contact with underground or overhead cables, faulty electrical appliances, and poor electrical installation.

When you factor in accidents caused by faulty equipment in rented properties, this figure grows exponentially. Both businesses and landlords are responsible for ensuring the safety of their employees, tenants, and the public. Ensuring all equipment is adequately PAT tested will help to prevent accidents and injuries. For more information about electrical safety for landlords, consult our knowledge base.

Having an up-to-date PAT test on equipment will also provide you with some legal protection if an accident or injury was to occur. Providing evidence that all equipment has been correctly maintained and has been deemed safe by a qualified PAT inspector could prevent you from being accused of negligence or failure to follow health and safety requirements.

What requires PAT testing?

Portable appliances that may require PAT testing include any equipment that can connect to a fixed installation or generator. This includes appliances that connect using a cable, socket, or plug. Any electrical appliances or equipment that is portable qualifies for PAT testing.

Furthermore, if your business uses any appliances that you would not consider portable but are plugged into a power source, these also will need PAT testing. This may include a dishwasher, industrial machinery, or a built-in refrigerator.

There are currently no regulations that stipulate which items should be PAT tested. Portable appliances are not necessarily moveable, and this is a common mistake many businesses make when performing PAT tests. Any object or appliance that plugs into a socket should be PAT tested, regardless of its size.

There are two main factors you should consider when deciding whether an appliance or object needs to be PAT tested:

• The category of the electrical item.
• The class of the electrical item.

What are the different categories?

There are several categories of electrical equipment that should undergo PAT testing:

• Fixed appliances – These are electrical items that are fixed in a permanent location or fastened to a support.
• Stationary appliances – Appliances that are stationary and are not moved, such as white goods in a kitchen.
• IT equipment – This is an item that is used for any IT purpose. Examples include computers, laptops, printers, and photocopiers.
• Moveable or portable appliances – Equipment that usually stays in one place but can be moved with relative ease. This type of electrical item usually weighs less than 18kg.
• Cables, wires, and chargers – Any cable, wire, lead, or charger that connects to an electronic item or plugs into a wall.
• Other handheld devices – Electric items that are held in the hand, such as electric tools and hairdryers.

What are the different electrical classes?

There are three different electrical classes.

Class 1:

This is the most high-risk and potentially dangerous class. Class 1 items usually have only basic insulation and instead rely on the earth for additional protection. Class 1 items will require a complete PAT test.

Examples of Class 1 appliances include:

• Industrial machinery.
• Vending machines.
• Washing machines/Tumble dryers.
• Dishwashers.
• Refrigerators/Freezers.
• Microwaves.
• Toasters.
• Kettles.
• Phone, laptop, and tablet chargers.
• Desktop computers.

Class 2:

This type of appliance will have additional insulation and does not rely on the earth. There is usually less risk associated with them. Class 2 items will require a minimum of a PAT insulation test but will often not require a complete PAT test.

Examples of Class 2 appliances include:

• Blenders and food mixers.
• Hairdryers and hair straighteners.
• Lamps.
• Televisions.
• CD players, DVD players, and radios.
• Lawnmowers.

Class 3:

This type of appliance is low voltage. Items categorised as Class 3 are usually low risk and the least dangerous. The appliance itself may not require an in-depth PAT test, although any chargers, wires, or cables will likely need to be tested.

Examples of Class 3 appliances include:

• Cameras.
• Torches.
• Laptops.
• Mobile phones.

Electrical items purchased in the UK should have symbols to identify what electrical class they are. It is recommended to consult this symbol to help you determine the level of PAT test it requires. For more information about understanding electrical symbols, consult our knowledge base.

What workplaces require PAT testing?

Although PAT testing is not a legal requirement, all workplaces are required to maintain electrical equipment in a safe condition. All workplaces must legally ensure the health and safety of employees and the wider public.

Because of this, any workplace that has any electrical equipment could benefit from PAT testing. Even if you are a small business that only uses basic electrical equipment such as lamps, laptops, and a kettle, you should still ensure the safety and maintenance of these items.

Work environments that may benefit from conducting PAT tests include:

• Industrial workplaces.
• Construction.
• Commercial environments.
• Educational establishments.
• Hospitality.
• Medical facilities or institutions.
• Rental properties, both domestic and workplace rentals.
• Any environment that is accessible to the public.

The more high risk your workplace is, the more likely it is that you will need to conduct PAT testing. When determining how high risk your workplace is, there are several factors to consider.

• How high risk is the environment? – Examples of high-risk environments are construction sites, gyms, arcades, and industrial buildings.
• What type of appliances are being used? – If the workplace contains Class 1 electrical items, this will result in a much higher risk level. Additionally, some electrical equipment, such as power tools, is much more dangerous and is often operated by multiple employees. This can result in a higher risk level.
• Who will be interacting with the appliances? – If the appliances are being handled by the general public, for example in a gym, this significantly raises the risk level as it is much more difficult to monitor whether the electrical equipment is being used correctly. Additionally, any workplaces where a lot of people will handle the equipment in a fast-paced environment will have a higher risk level.

Workplaces with a higher risk level will need to conduct more frequent PAT tests and ensure they record the results of their inspections concisely.

How often should items be PAT tested?

As PAT tests are not required by law, there is no specific rule regarding how often testing should take place.

The frequency of your PAT tests will depend on several factors, including:

• The risk level that is associated with the working environment or the environment the electrical appliance is used in.
• The category of the appliance.
• The electrical class of the appliance.
• The age of the appliance.
• How frequently it is used and the way in which it is used.
• Any recommendations provided by the manufacturer.
• Any repairs, modifications, or part replacements that have been made.

Who can perform a PAT test?

UK law stipulates that PAT tests can only be completed by a competent person.

The Institute of Electrical Engineers (IEE) defines that as someone who:

• Has adequate knowledge of electricity.
• Has prior experience working with electricity.
• Has a good understanding of any potential electric hazards.
• Understands electricity at work regulations.
• Takes all necessary precautions.
• Has an understanding of the electrical appliance.
• Can determine whether an electrical appliance is safe or whether it is safe for any work to continue.

The most qualified individual for performing a PAT test would be an electrician. However, in some businesses, especially smaller ones that need to consider the financial implications, this may not always be possible. In this situation, a business can elect an employee to take a PAT testing course run by a qualified instructor.

Once this individual completes the course, they will then be qualified to conduct any PAT testing, including visual inspections, and use PAT testing equipment. In this situation, the business will need to purchase a PAT testing machine in order to carry out in-depth PAT tests.