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Electrical Fire

What causes an electrical fire?

Electrical fires have been at the forefront of the news a lot recently due to several high profile events, but how much do we know about what causes an electrical fire, how can we prevent them happening and what can we put in place to help contain them if they do break out?


Electricity is often overlooked as a potential source of fire as there is no visible flame, yet around 28,000 fires in the home are reported each year to have started from an electrical fault, accident or misuse of equipment. On New Year’s Day 2018, an eco-home that took six years to build and previously featured in the TV programme Grand Designs was burned to the ground. The owner reported that it started in a junction box downstairs. Jasmine Dale, the owner, was quoted in The Telegraph saying: “The fire was caused by a freak electrical fault. I was in the house just a few moments before the fire broke out, and there is a junction box downstairs with many electrical wires.”


Such was the devastation of the fire, the house was completed destroyed and we’re never likely to know the root cause of the fire within the junction box. There are however several possible causes that using good engineering practice and installation methods can be minimised. The phrase “many electrical wires” is worrying. Most standard domestic style junction boxes are designed to take a maximum of 4 cables and have 4 cable entry points. Having too many cables bunched together will affect how the heat dissipates from the cables, increasing the ambient temperature.


Most junction boxes have screw terminals and if these are not fixed correctly, the resistance is increased in the circuit. Where resistance is raised, there will again be more heat given out by the circuit. Loose terminal screws are often a source of electrical fire because of this, and all electrical terminations should be in an area suitable for regular inspection so they can be tightened as required. They are not suitable for mounting behind plasterboard and forgetting about. Special maintenance free connectors and installation methods can be used for areas that cannot be accessed in the future. Many electricians or DIY’ers continue to use junction boxes as they are cheaper.


It is also possible, if the termination was poor within the junction box, that a short circuit could have arisen from two bare cables touching, or being too close, causing an electric arc. An arc has a huge amount of energy which could start a fire if the circuit breaker did not operate as it should (if the circuit has been poorly designed). It is important when adding a new circuit, or modifying a circuit, that you ensure that the maximum amount of resistance in the circuit allowed is not exceeded.


Junction boxes are also not a one size fits all. Some smaller units are only rated at 5 amps. Larger ones tend to be 20 amps. When selecting your materials, ensure that they are suitable for the job at hand. All parts of electrical systems should be to the relevant British Standard, and marked accordingly. Only use reputable suppliers and be cautious as due to the rise of online marketplaces, lots of cheap, sub-standard counterfeit accessories are being sold on a daily basis.


The environment that the box is placed in should also be considered especially with regards to insulation and the box should be of a suitable material for its environment. Since the introduction of Amendment 3 of the wiring regs, all consumer units in domestic settings need to be constructed of a non-combustible materials, usually metal. A metal enclosure with suitable sealed knockout holes will contain a fire within it, stemming the spread. Envirograf manufacture an excellent item called the Envirobust Tube – a plastic tube that bursts open at 70℃ that contains a fire suppression liquid.


Electrical fires are not only caused by DIY installers, faulty equipment or poor install methods. Appliances cause a large amount of fires, most notable the fridge that was the reported cause of the tragic events at Grenfell Tower in 2017 where 71 people lost their lives. Use them in the manner they were intended, protect them from water, and make sure you register them with their manufacturer when you purchase them to be notified of any product recalls. Don’t leave electric heaters unattended and keep them away from curtains. Ensure they are kept in good working order, check cables for fraying and any signs of burning or scorching. If a fuse blows, make sure you replace it with one of the same rating. A 13a fuse in a thin cable won’t protect it, and could cause a fire. If the fuse keeps blowing, it’s because there’s a problem – get it fixed or replace the appliance.


Overloaded extension leads are also a large cause of fires both in the home and at work. Avoid plugging in high powered devices (as a general rule, things that produce heat such as kettles, heaters, cookers use the most power) into extension leads, this useful calculator will help, but is also complicated by the fact lots of extension leads on sale now are not rated at 13a. Some 10a and 5a leads are available, and are cheaper as they use thinner cable, but should only ever be used for low powered equipment such as IT or audio/visual equipment & lamps. It is recommended that extension leads are never used as a permanent fixture, however we all know this isn’t practical, so be careful.


Fires are not only started in the home or office. In January 2018 a fire broke out on the rooftop of Trump Tower in New York, a 58-story skyscraper built in 1983 by the man who went on to become the 45th President of the USA, Donald Trump. It was reported to be caused by an electrical box in a cooling tower and rooftops of large buildings often contain a large amount of plant, most notably air conditioning systems. In this instance, it was actually spotted by the Secret Service who monitor the building for threats and it was dealt with quickly and easily by the FDNY with 3 minor injuries to crew working at the blaze. We’ve not all got the Secret Service monitoring our buildings, but it goes to show that early detection is important in all cases, and this can be done in residential, commercial and industrial environments by the use of fire detection systems, allowing a small fire to be tackled with appropriate extinguishers or the building to be safely evacuated while you wait for Fire & Rescue. Plant rooms and areas are always a risk as they contain lots of equipment, are mostly left unattended and have high ambient temperatures.


Avoiding electrical fires should be something considered at all points of a building or electrical installations life; at the design phase, while being built/installed, during use and maintenance and also, often overlooked, during a change of use that may mean existing systems are no longer suitable.

Push switch

Part M Switches and Sockets

Since it’s introduction in 2004, Part M of the building regulations aims to make it easier for people with a disability to use and access buildings. You may have noticed that buildings now have ramps, wider doors, railings and more to allow easier access. Electrically, Part M is concerned with switches, sockets and other controls. The implementation of Part M will not only help people with disabilities, it can also aid the elderly, hard of hearing or visually impaired. Primarily, it’s focus is on commercial buildings with some slight differences between dwellings & non-dwellings.

Part M contrasting colours

Part M Socket
Part M socket with green contrast switches for use on a dark wall/background

Part M states that to aid visually impaired people, the colour of electrical accessories should contrast the wall so that they can be easily identified. On top of this, the actual switches on the faceplates should further contrast so they stand out. If you’re using all white switches and sockets on white or magnolia walls then you’re not compliant.

Rocker switch positioning

If you have a look at most standard double sockets, the two switches are often arranged next to each other in the middle of the socket. To people with limited dexterity or the visually impaired, it can be hard to differentiate between the two. Part M double sockets have the switches arranged at each side of the faceplate, aiding ease of use. These are known as ‘outboard rockers’.

Positioning on the wall

Part M outlines recommended outlet positions for items such as light switches, sockets, TV outlets and other controls such as thermostats. The exact end users should be taken into consideration for this, as wheelchair users would require lower light switch positions and possibly higher socket positions than other users.

Wide switches

Part M Light Switch
Wide switch for users with limited dexterity or visually impaired people
Rather than using normal sized light switches, to help visually impaired or users with limited dexterity, special wide switches can be fitted to make the job of turning lights on & off much easier.

Locating plug sockets

Locating plug sockets
Locating plug socket with V groove to allow easy location of the earth pin. Available in Part M dark grey with white switch, all white and in single and double configurations.

Some plug sockets are designed with a special V shape that allows the earth pin of the plug to be easily located & let down to the correct hole. If you’ve ever tried to plug an appliance in behind a piece of furniture you’ll know how difficult this can be – this is what visually impaired people go through on a daily basis. These sockets can also help people who suffer from hand tremors, or just for sockets that are going to be hidden behind wardrobes, racking, shelving or other large pieces of furniture that aren’t easily moveable.


All commercial or industrial buildings, with particular focus on public buildings and the healthcare sector.

Give us a call

For a free, non-obligation quote, get in touch to book an initial site survey.

0330 223 16 55

Lines are open during office hours, Mon-Fri 08:30-17:00. Out of hours, leave us a voicemail and we’ll get back to you, or email us here.

Find out more about Part M and your obligations by downloading the pdf documents from the Planning Portal here.

Hotel Key Card Switches

Hotel Key Card Switches

Improve energy saving in your hotel, B&B or guesthouse

Hotel Key Card switches improve energy saving by working as the main switch in a hotel room. They’re easily operated by the guests, with lights and electric heating only becoming operational when the guest enters the relevant card into the switch. This saves energy by stopping the room being necessarily lit, heated or cooled when it isn’t occupied. When the card is removed, the switch can be set to let the power stay on for a pre-defined amount of time (from 10 seconds to 5 minutes) .

Glow in the dark

The switches come with a small LED indicator, allowing guests to easily find the switch in the dark, so no additional lighting is needed to be fitted. The switches are designed to fit standard key card sizes of 85.60 mm × 53.98 mm, which is the same as a credit or debit card.

Switching ability

The switches are designed to switch up to a 6 amp inductive load or a 10 amp resistive load, meaning that they can be retro-fitted to nearly all rooms with ease. Larger loads such as air-con systems can also be controlled via the use of a contactor.

Looking the part

The switches come in a range of finishes, meaning that it won’t look out of place with your existing faceplates. Styles include white, chrome, stainless steel, brushed steel, polished brass, matt black, black nickel and more. With access to the full range of light switches, power and media sockets from the Click range, if you wanted to add these as part of a full refurbishment we can make sure everything matches perfectly.

How much will I save using hotel key card switches?

This really depends on your occupancy rate. The average hotel room has a 65% occupancy rate & of that, the guest is in the room for around 40% of the time. If you are currently heating, cooling, or lighting the room for the large periods of time nobody is in it, then you should see savings of more than the cost of installation.


Hotels, guesthouses, serviced apartments, bed & breakfasts, offices

Give us a call

For a free, non-obligation quote, get in touch to book an initial site survey.

0330 223 16 55

Lines are open during office hours, Mon-Fri 08:30-17:00. Out of hours, leave us a voicemail and we’ll get back to you, or email us here.

Emergency Lighting Testing

Emergency lighting systems are your guardian angel when trying to exit a building in a safe manner during a power cut or urgent situation. Failure of your system is not an option either for the occupants or duty holders. For this reason they should be thoroughly inspected on a regular basis. The following are minimum inspections & tests that should be carried out.

Daily Tests

These will only apply if you have a central back-up system. A central back-up emergency lighting system uses a central power supply (battery) to power a range of emergency lights (luminaires) – it is very important that this power supply is operating correctly as it’s the only thing that will keep your luminaires working in the event of a power failure. A daily inspection of the indicators on the power supply should be carried out. No test of operation is usually required on a daily basis.

Monthly tests

All emergency lighting systems should be tested on a monthly basis. A failure of the lighting circuits should be simulated, during this time all luminaires and signs must be checked to ensure they are;
• Present
• In good condition
• Functioning correctly

Annual tests

Once a year, a test must be carried out for the full rated duration of the lights (for example, 3 hours). The rated duration of the lights can be found via a code on the side of the casing. Emergency lights must still be working at the end of this period of simulated failure.
Careful consideration should be taken towards the timing of this test – the normal lighting may fail during the testing or battery recharge period leaving the building without sufficient emergency lighting. A time of low-risk must always be chosen. Where buildings are always occupied, only test alternate luminaires at any one time & provide backup using temporary means.

Other considerations

All tests must be recorded. Any failures detected must be remedied ASAP. Batteries in luminaires must be replaced on a regular basis – manufacturers will issue guidelines based on your particular accessories. Systems must always be designed to BS 5266-1:2011 & you should have been issued with a certificate of compliance when the system was commissioned.

If you require help with your Emergency Lighting Testing, Peeko can provide a range of solutions, from a fully managed solution for your piece of mind, annual inspection & testing or an on-site training course to allow you to perform tests in-house. Get in touch for a free non-obligation quotation.

PAT Testing

PAT Testing Risk Assessment Approach

As many of you know, the old adage that PAT testing must be carried out annually is a myth that has been spread by bad PAT testing companies looking to make more money out of you. Some businesses will test many of their items annually, some may be bound by a tenancy or lease agreement that specifies when to test the items. Many business will not have the luxury of such fixed rules, and the latest recommendation from the IET is to take a ‘risk assessment’ based approach to PAT test frequencies. How is a business owner or safety manager, with limited knowledge in this area supposed to make an informed judgement?

The IET publish their recommendations as to how often to re-test with each revision of their code of practice, and we’ve included that on our website for you here. These recommendations are to be used as a starting point for your risk assessment. From there, take each group of items you have, PCs, kettles, extension leads etc, and take the following items into consideration, and increase or decrease the frequency as required.

PAT Testing Risk Assessment – 10 Point Plan

1. Type of equipment – (Stationary, Information Technology, Portable, Moveable, Handheld).

2. Style of use – (infrequent, constant, rough).

3. Age of equipment.

4. Is the equipment moved or transported anywhere and by what means?

5. Type and competence of personnel using the equipment.

6. Environment of usage (outdoors, construction sites, hazardous atmospheres etc).

7. Results of previous test – if a particularly large number of appliances failed or required repair it might be worth increasing frequency until issues are solved.

8. Any recommendations by the manufacturer.

9. Effect of any modifications/repairs to the item.

10. Likelihood of user-checks taking place – many business we test put these in place with the best intentions, but the reality is they do get overlooked in many cases.

School PAT Testing

School PAT Testing

Finally, the summer is upon is. And I don’t just mean the weather. Children and teachers from all over the country are welcoming the start of the summer holidays. But it’s not fun for everyone involved; caretakers and estates managers are about to embark on one of the busiest periods of the year. The traditional 6-week break is the perfect time to get all the necessary maintenance work done, both from a practical aspect and a safety point of view.

All manner of trades will be busy over the next month and a half, desperately trying to get finished on time for the return of the academic year in September. Electrical work will be completed by electricians, commercial decorators will paint miles of walls and get through tens of thousands of litres of paint; but who will do the school PAT testing? The past decade has seen a rise in the amount of companies and organisations ‘in-sourcing’ – that is, no longer using a contractor and starting to perform certain tasks internally. But is this still a cost-effective method?

School PAT Testing

It boils down to the age-old theory of supply & demand. Organisations in-source = reduced demand. However this increased the demand for PAT training companies, which has left us with more people than ever who are deemed competent to provide PAT testing services. This increased supply coupled to the reduced demand lowered prices dramatically across the nation. Many companies are now paying less than half of what they were paying 5 or 6 years ago. Many companies we talk to who haven’t renegotiated their rates with their current provider for some time, are shocked at how much lower the rates are.

In-House PAT Testing Costs

Let’s run through an example and at the end hopefully you’ve got enough information to use your own figures and see if it’s a cost-effective solution for your school.

1. Fixed costs (one-off)

Training for 1 person – £300*

PAT Tester, tools & accessories – £400

*Please bare in mind that if the trained member of staff was to leave for another job, you may have to re-train another person.

2. Fixed costs (annual)

PAT Tester annual calibration – £40

3. Variable costs (per item)

Test label – £0.02

Fuses – £0.01**

**Based on a wholesale price of 10p per fuse. Approximately 1 in 10 replaced. Expect this to be higher for new IT equipment.

4. Labour costs

Per item, this will be your biggest variant. It depends on a number of factors:

  • Staff member salary – Average caretaker salary is believed to be £17-20,000 per annum, although some earn much more.
  • Overtime rate – If the staff member cannot perform PAT testing within their regular working week, you may be contracted to pay overtime rate.
  • Speed of staff member – An infrequent PAT tester would be expected to average around 12 items per hour, which could drop as low as 10 or rise as high as 15 with regular practice.

£18,500 ÷ 52 (weeks) ÷ 40 (hours per week) = £8.894 per hour (assuming no overtime or enhancements are payable)

£8.894 ÷ 12 (items per hour) = £0.74 per item (Labour only)

5. Total cost per item

Without overtime: Labour + Variable = £0.74 + £0.03 = £0.77 per item
With overtime (at time & 1/3rd): (Labour x 1 1/3) + Variable = £0.99 + £0.03 = £1.02 per item

Please bare in mind these are just examples, based on a salary of £18,500 per annum and an overtime rate of time & 1/3rd. Substitute these for your own figures and work out your own estimate. We’ve provided a handy calculator within an excel document you can download at the end of this article.

So, lets put these prices into context as they are a little meaningless at the minute. Are they cheaper or not?
Well, they are both much cheaper than what you would have paid in the previous decade, which explains the sudden increase of in-house PAT testing, but aren’t necessarily cheaper than you would pay now. For anything over 200 items (which is what most schools would be, some into the thousands of items) we would comfortably be able to beat the £1.02 estimate nationwide. As for the cheaper quote, with a large number of items, we could certainly get very close, maybe even beat it on a multi-year contract, but let’s consider if it is cheaper first. Let’s compare it with a quote of £0.84. It’s 7p cheaper on face-value, but we need to now consider the fixed costs, firstly the annual PAT tester calibration.

£40 ÷ £0.07 = 571

This means you would need to perform a minimum of 571 tests per annum to cover the cost of calibration. Every 571 tests after this you would save £40. Is this worth burdening your staff with the extra responsibility & workload? To hit your £40 saving it would require you testing 1,142 items, which many schools will have, but that’s approximately an extra 95 man-hours of work! Let us not forget the other one-off fixed costs – you need to make sure that you are making enough of a saving each year to cover your initial capital expenditure.

£700 ÷ £0.07 = 10,000!

This means, that you would need to perform a total of 10,571 tests before you hit your break even point with an extra 571 items added for every year it takes you to get there! For many schools this isn’t realistic as it would take years to reach that figure.

In-Source or Out-source PAT?

Each school will be different as each has different costs to consider. If you are looking at bringing PAT testing in-house now, in 2013, my advice would be don’t bother. As you can see from the example above and your own calculations that you’ve hopefully done, it will take years to break even and if you are constantly paying to retrain new staff you may never hit your break even point. If you are a very large school and able to hit 10,000 items in a couple of years, re-negotiate your rates with your current provider or get a quote from others.

If you currently in-source then it’s worth re-evaluating based on 2013 quotes and salaries. You may find that as your labour costs have gone up, the newer PAT quotes are significantly less that when you first decided to in-source and it is no longer viable to continue. Then it would be beneficial to enlist the services of a contractor.

It maybe that your one-off fixed costs have been covered over the previous years, so you don’t have to take that into account and it runs at a similar cost to a contractor, in which case you have a couple of options; it maybe that you can better utilise the expertise of the staff member elsewhere, so a PAT contractor would free up the time to do this, without having to pay staff overtime or, you could happily leave the arrangement as it is currently, to again re-evaluate the costs should your trained staff member leave the organisation, in which case re-training may not be worth it.

To perform your own calculations, you can use our handy excel based calculator here.

Misrated Fuse

Common PAT Testing Failures

Here are some examples of common PAT testing failures we find to give you an idea of what is deemed safe or not. It is important that the duty holder and end user have a basic knowledge of these items, so that any appliance that becomes unsafe between test periods gets removed from service and/or suitable repairs are carried out by a competent person.

Misrated Fuse

1. Incorrect Fuse Fitted

While there is an agreed standard for new electrical appliances, incorrect fuse ratings are still the most common issue found when PAT testing. With modern appliances anything that uses less than 700W of power should be fitted with a 3A fuse, anything above 700W a 13A fuse. While this works, and was designed to simplify the process, it’s not always adhered to and can be improved upon.

13A wall sockets are good for anything up to 3000W of power, therefore a general rule of thumb often applied is each 1000W draws approximately 4A of current, therefore needs a fuse rating slightly higher than that to protect the wire. In the event of an appliance entering a fault condition, a surge of current will blow the fuse, break the circuit and stop a too high current flowing down the wire. If the fuse rating is too high, it may not blow, potentially allowing a current too high to pass through the cable, which left over time will cause a fire.

How is it corrected? Your PAT test engineer will replace the fuse with the correct rating and your appliance will be safe to use.

2. Cracked or Damaged Plug

Damaged Plug

Any cracks or damage to the plug, or excessive damage to the appliance itself that may expose it’s electrics will fail. A cracked or damaged plug, could potentially be an electric shock risk when the end user is removing or plugging in the item. A cracked case that exposes the electrics inside, would also be a fail for the same reason.

How is it corrected? A cracked or damaged plug would be replaced by your PAT test engineer. An item with a damaged case will most likely need replacing, insulation tape is not an acceptable repair. If spotted before your PAT testing is due, they should be repaired or removed from service.

3. Non-Insulated Live and Neutral Pins

Non-insulated Live and Neutral Pins Despite not being manufactured in this style for many years, these plugs still crop up from time to time. Newer, modern plugs have the Live and Neutral pins insulated to stop the users fingers making connection with the metal when the plug is partially inserted, during plugging & unplugging of the appliance. Whereas if the plug and socket is the correct size and shape, the user shouldn’t be able to make contact with the pins until they have been disconnected from the source, there have been instances where people have used metal implements to remove a stuck plug and made contact. A common trick amongst school children was to wedge a 1p piece between the pins to create an explosion when plugging in – this is a very unsafe practice, potentially injuring the user, causing a fire and damaging the whole electric circuit. These plugs are very dangerous if used incorrectly and should not be used.

How is it corrected? These will be replaced by your PAT test engineer. If spotted before your PAT testing is due, they should be repaired or removed from service.

4. Earth Pin Insulation

Insulated Earth PinAs a complete opposite to the above problem, the plug attached to the cable to the left has the earth pin partly insulated that it shouldn’t have. We’ve covered this before on our Counterfeit Plugs blog post so have a read of that if you want details, but when this is plugged in, it won’t make the earth connection as required.

How is it corrected? These items are generally counterfeit cables, stamped as meeting the BS1363 when they don’t. The plug cannot be swapped as there is no way in telling if the rest of the cable has been manufactured with sub-standard materials. You should remove them from service, contact the supplier who you purchased them from for a full refund, and inform trading standards.

5. Damaged Flex

Damaged FlexExcessive wear and tear to the cable is also considered dangerous and the item should be removed from service if spotted. If any more damage was to occur to the flex in the image, bare wires would potentially be visible, creating a shock risk if the wire, or a conductive item that made a connection to the wire, was touched.

How is it corrected? In nearly all cases, damaged flex can be disconnected from the appliance and refitted with a direct replacement, or one with a heavier-duty sheath.

PAT Testing for Home Workers

PAT Testing for Home Workers

I’d like to thank everyone at Google for their excellent Google Analytics tool. Not only does it allow you to track visitors to your site in great detail, you can even find out how visitors find your site in the first place, what search engine they came from and what search term they used. Yesterday a visitor found my site by using the search term ‘PAT Testing for home workers’, which made me realise that;

  1. I had nothing on the site that explains whether home workers need to have their equipment PAT tested or not and,
  2. I wasn’t 100% sure whether home workers need to have their appliances tested or not!

I started doing a little bit of digging around to help find the answer and as usual the answer is, it depends!

PAT Testing for Home WorkersFirstly, it depends on who is providing the equipment. If you are ’employed’ as opposed to ‘self-employed’ then it’s likely that your appliances have been provided for you by your employer, therefore it’s their responsibility to ensure that any electrical items they provide are safe to use. The way most employers comply with this is through regular PAT testing so make sure that your items are done for you – speak to the responsible person within your organisation to see when the engineer is due or you may have an internal PAT tester that you can take your equipment to. It’s in your interest to get this done if you’re taking these appliances into your home – any potential of electric shock or fire now not only puts you at risk but anyone who shares your home. Your appliances may also be classed as a higher risk than normal if they’re regularly transported from home to office and back again, as opposed to static appliances sat on a desk, so depending on your company’s risk assessment, you might even have to have your items tested more frequently.

Secondly, it will depend on what sort of appliances you’ve been provided with. Laptops, mobile phones and tablet PC’s are exempt – you may sometimes see these defined as Class III or SELV appliances – basically they run off such low voltage you don’t need to worry about it. However, you will have mains chargers for them all, and they will require testing. How often really depends on your company’s policy, if they don’t yet have one you can check our list of recommended PAT testing frequencies. Brand new equipment won’t need testing, so if you’re anything like me and get through laptop chargers for fun, you might have new equipment more regularly than the test frequency, in which case you won’t have to bother. Remember to date your new equipment with a marker when you receive it or you’ll forget how old it is!

If you’re a mobile worker, regularly visiting different workplaces you’ll be bound by the policy of the company that you’re visiting, so make sure you check beforehand. IT equipment generally isn’t a problem, but I have heard of instances of people being refused entry, generally in more industrial environments and on building sites.

For the self-employed home worker it’s a little bit different. I can understand why someone’s initial reaction would be to not carry out PAT testing, especially if you are just using the same items that you would have in a home office/study if you weren’t a home worker. If you employ anyone else that works from your home office then it’s a definite ‘yes’ to have it done, you need to make sure your staff are using equipment that’s safe in the same way any employer would. If it’s just yourself I would still advise to have it done – insurance companies will look for any 1/2 excuse they can find to not pay out in the event of an accident – so I’d say take a common-sense approach and don’t take the risk. A test every 2 years would be sufficient, and would probably average out at £20 a year for most home offices.

A larger risk to working from home is overloaded sockets, especially when using extension leads when there aren’t enough available. Try our socket overload calculator to see if yours are safe.*

Bring Your Own Device PAT Testing

If you work for a company that has a Bring Your Own Device policy, then we hit yet another grey-area. If you are using your device on company premises, then it should be covered by the company as they have a duty of care towards other employees in the area. Using your own devices saves the company money by not having to invest in new technology, so it would be quite an unreasonable employer that makes you PAT test your own! It will vary and most companies won’t have even considered it, so your best option is to speak to your boss and find out.

*Socket Overload Calculator kindly provided by the Electrical Safety Council.

Counterfeit Plugs

Counterfeit Plugs

It seems that a suspect batch of counterfeit plugs has entered the UK market. Many of us will have been stung online before with counterfeit goods, either from internet auction sites or other outlets but it’s not the branding that is in question with these items – it seems they have been molded as BS1363 (the British Standard for a normal 3-pin plug) but don’t meet the requirements. If you have recently had your items PAT tested then you should be fine – an experienced PAT tester would pick up the problem at the visual inspection stage, failing that the lead and plug would fail the earth bond test. It is easy to spot when you’ve seen one – the earth pin (the longer pin at the top of the plug) is half insulated (see image below).

Counterfeit Plugs
Earth pin (on the right) is part insulated.

To meet the British Standard, this can be fully plastic for Class 2, non-earthed appliances – you may have mobile phone chargers and other low-voltage power supply units like this – but for all other appliances it should be solid brass with no insulation. The live and neutral pins are supposed to be insulated, this is to protect the fingers as the plug is removed – the pins will be disconnected from the mains (connection is made at the back of the wall socket) before the user can touch any metal part. However the earth pin connects at the front of the socket. This is so that when the appliance is being plugged in, it is earthed safely before the live and neutral pins are connected and current begins passing through the item. It remains safely earthed until after the live and neutral pins are disconnected when unplugging the item. If the above lead was to be plugged into a wall socket, the metal earth connectors inside the socket would be touching the plastic insulation, not making an earth connection as required.

BS1363 IEC Lead
The earth pin on this IEC lead conforms to the British Standard and would make a safe earth connection

Why is this important?

In the event of a problem with the appliance, such as a connection between a live wire and a metal part of the appliance, the earth pin is designed to make sure the current flows safely to ground, and that the user isn’t at risk of getting an electric shock. The insulation on the earth pin will break this ‘safety circuit’ and the metal parts of the appliance will potentially be carrying a live electric current.

What should I do about it?

The easiest thing to do is get staff to double-check all your equipment. A quick visual inspection will find the problem. In the event you find any items with semi-insulated earth pins, remove them from service immediately. If you know where that particular lead has been purchased from, contact the retailer for a full refund. Trading Standards should also be made aware if you think the retailer/manufacturer is knowingly selling these counterfeit items. IEC (kettle leads) cables that supply power to many appliances, such as PCs, monitors and printers are the most common kind found. Do not attempt to repair with a replacement plug as other sub-standard materials may have been used in the production of these items.

What is a Portable Appliance?

So your PAT testing is due, you’re in the process of getting quotes and you’ve been asked how many items you’ve got that require testing. How do you define what is a portable appliance, what isn’t and what needs testing?

A common myth is that the appliance has to be below 18kg in weight – this is incorrect and this only defines whether an appliance is classed as portable/movable (below 18kg) or stationary (equal or above 18kg). An example may be a fridge or washing machine – these would almost certainly be over 18kg, however are still appliances, still pose a risk to the user and are still ‘movable’ in the dictionary definition of the word. Due to the weight, and fact they are moved more infrequently compared to small appliances, they would be classed as stationary objects for PAT testing frequency reasons.

The easiest way to grasp what needs PAT testing and what doesn’t is to completely ignore the term PAT testing, especially the ‘Portable’ section of it. The IET are making moves to change the name to ‘in-service inspection & testing of electrical equipment’ which is a bit of a mouthful but more accurately describes the process. ‘Electrical equipment’, that is ‘in-service’ gets ‘inspected & tested’. The IET are using this phrase inconstantly in their documents and I personally don’t see it catching on – Electrical Appliance Testing or simply Appliance Testing might be a more suitable way of thinking about it.

Short answer – if it has a plug on it, test it!

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