Do you run a business and have any number of electrical appliances in your working environment? Do you conclusively know if they are safe to use? If your answer is no, then you should arrange PAT testing for them.

If you aren’t quite sure what this means or entails, our guide will cover everything you need to know about what PAT testing is and when it is required.

PAT: The Electrical Safety Test

What is it?

Portable appliance testing, more commonly known as PAT testing, involves the inspection and testing of electrical equipment to determine whether or not it is safe to use.

It is not a legal requirement to undertake PAT testing, however, in accordance with the Electricity at Work Regulations 1989, all businesses are legally required to maintain any and all of their electrical equipment (that has the potential to cause harm) in a safe condition. PAT testing is the most reliable and common way of ensuring this.

PAT testing is typically aimed at business owners, landlords and public sectors (i.e. schools, hospitals etc.), since they are providing the electrical appliances for use by other individuals.

Can I Conduct My Own PAT Testing?

When it comes to visual inspections, a knowledgeable and trustworthy member of your staff may be able to test your electrical appliances for visual defects. When it comes to manual testing, however, then you will need a competent individual with more knowledge and expertise to carry out the appropriate tests.

This is why employing a trained electrician is advised. Not only will they know what tests need to be carried out, they will also have the appropriate equipment to perform said tests along with the knowledge on how to use this equipment properly and understand the results.

What is Tested?

Visual inspections are the first part of any PAT test. This involves checking the plug socket and cable of the appliance, looking for any cracks, bent pins, exposed and fraying wire, as well as observing the appliance itself for any obvious damage, such as corrosion, burns marks and broken pieces.

Manual tests are then conducted using specialist equipment that looks at hidden factors, such as lead polarity, earth continuity and insulation resistance. More in depth tests may also be carried out on top of this.


There are different types of equipment that could be used to carry out a PAT test as well as a standard PAT tester. These include:

– A multimeter: These test for multiple electrical properties, including current, resistance of electrical insulation and voltage. Because of their ability to test for multiple electrical properties, these are an essential piece of equipment for PAT testing and can ensure that an appliance is safe for use.

– A polarity tester: These test the polarity of the electrical circuit. They work by connecting a probe to the neutral wire and another probe to the live wire, then measuring the voltage between the two; ideally, the reading will be 0, meaning no current is flowing between the probes and the appliance is correctly wired.

– An earth leakage tester: These measure the amount of current flowing through the earth wire, checking that it is not too high – if it is, this could present a shock hazard.

– An insulation resistance (IR) tester: These measure the resistance of electrical insulation materials by attaching two probes to the insulation material and measuring the voltage that passes through it. The results will allow the electrician carrying out the test to determine if the insulation material is suitable or if it needs to be replaced.

– A voltage tester: These test the insulation of an appliance and see if they are properly grounded. Lack of proper grounding means electrical charge builds up in the circuit of an appliance, causing gradual damage that could shorten its lifespan, or even pose a shock and fire hazard.

– A continuity tester: These measure the electrical continuity, such as testing for loose connections or breaks in the circuit. If the circuit is continuous, then the continuity tester will emit a sound and light up, if there is a break or issue in the circuit then it will remain unlit and silent.

How Long Does it Take?

PAT tests are generally very quick procedures when you look at it per item. It takes approximately 2-5 minutes to perform the test on a single appliance; that makes it possible for as many as 30 appliances to be tested within the space of an hour.

Of course, this time will vary depending on how many appliances you have and how accessible they are. If you are a large I.T. business, for example, then a full PAT test of all your appliances could take up to the full length of a working day, whereas for a small, independent coffee shop this could be done in a few hours at most.

Accessibility to appliances also affects the rate at which PAT testing can be carried out. If your appliances are not readily available to be unplugged from the mains and not be in use, or are disorganised and not easily accessible, then the process of PAT testing will ultimately take longer as a result.

Why PAT Testing Is Important

You may think that PAT testing is a waste of time and money for your business since it is not a legally required practice, however there are a number of benefits that outweigh this mere inconvenience. These are as listed below.


There’s no doubt that PAT testing is important first and foremost for the safety of your staff.

By regularly testing your electrical equipment, you can rest assured that it is reliable and unlikely to cause injury to any of your staff. This also means that your staff will be able to use any electrical appliances without any anxiety, hesitation or concern for their wellbeing.

Preventative Maintenance

Regular PAT testing is a great preventative measure to take when it comes to the reliability and usability of your electrical appliances.

By identifying any faults your portable appliances may have through PAT testing, you will be able to fix any issues before they get worse. This could be the case of repairing or replacing a specific component of the appliance rather than needing to replace the whole thing all together.

This saves you money in the long run and allows you to keep on top of what appliances you have and their quality.

Legal Compliance

Despite regular PAT testing not being a legal requirement in and of itself, as a business owner it is your legal responsibility to ensure that all your electrical equipment is safe to use.

PAT testing is the easiest, most reliable method of guaranteeing this. Not only that, but it will also likely ensure that your business is in keeping with any insurance requirements relating to the safety of your employees in the workplace.

Passing or Failing a PAT Test


If you pass a PAT test, then a green and white sticker saying ‘passed’ will be stuck onto the appliance.

This sticker will have the date (typically month and year) that the appliance passed the checks, what number the appliance is from your inventory and the initials of who it was carried out by. It will also show the date when the next test is due (for most standard equipment this will be a year or two after the pass date, however equipment that is used more vigorously may require more frequent testing).


If you fail a PAT test, then the electrician carrying out the test will often see if the problem can be fixed and, if they can, repair it for you straight away; this could include replacing fuses or damaged parts of a plug, rewiring plugs, or repairing damaged cables amongst other things. If this is the case, then they will retest the appliance once it has been fixed and change the mark on their report from fail to pass.

If, however, your appliance cannot be repaired immediately or needs to be replaced, then it will be issued a red and white sticker saying ‘failed’. This sticker will also instruct that the appliance do not be used, since it will be dangerous to do so.

When your appliance fails a PAT test, it is recommended that you remove it immediately or as soon as possible to avoid anyone accidentally using it. Not only could they injure the user, but faulty appliances pose an electrical fire risk, threatening the safety of everyone in the surrounding environment.

Local Electricians

Do you need PAT testing for your business, you need Sheaworks Ltd.

Our skilled electrical contractors can carry out thorough PAT tests, providing you with certificate confirmation that your commercial electrical appliances are safe to use. In the case that they are not, we will inform you of any faults that have been found and how these need to be repaired, offering our own reparation and rewiring services to you.

If you require commercial PAT testing for your company, or are looking for other electrical services, then contact us today. We offer electrical installation in London, as well as electrical testing and repairs.