Safety Advice: Plugs and Fuses

How to check your plugs are safe

It’s a good idea to check plugs and plug wires regularly. Plugs and their cables can be damaged with use. Here’s how to check the common, square-pin 13-amp plug used in all modern appliances such as hairdryers, vacuum cleaners and microwaves.

With the plug removed from the socket, check the cable:

  • Is the cable securely attached to the appliance and the plug?
  • Is the cable cut, nicked or damaged in any way?
  • There should be no joints and no repairs with insulating tape.

Then, check the plug:

  • Look for cracks or damage on the casing.
  • Look for signs of overheating, such as discoloured casing or cable.
  • Check the plug meets British Standard BS 1363 – it will be marked on the back.
  • Check that the plug cable is firmly clamped into the plug and no coloured plug wires are showing.

For plugs that did not come fitted to the appliance, check that the cable is connected correctly. 

Remove the plug from the socket, and remove the cover.


  • The brown (previously red) plug wire goes to live (L).
  • The blue (previously black) plug wire goes to neutral (N).
  • The green and yellow (previously green) wire goes to earth (E).
  • The cord clamp holds the cable securely and that both of the screws are tight.
  • The screws holding the three plug wires are tight.
  • The fuse is the correct size and meets British Standard BS 1362 – see the manufacturer's instructions if you are not sure what fuse to use.
  • The fuse clips securely into its holder. It should not be loose and there should be no signs of overheating.

Replace the cover securely.

How does a fuse work?

The fuse in a plug is a safety device designed to protect the lead rather than the appliance. It is a deliberate weak link in a circuit which will 'blow' if an electrical appliance or extension lead draws too much current due to either an overload or a fault. The blown fuse cuts off the electricity to stop the lead and appliance from overheating and causing a fire.

Different types of fuses

As a rule of thumb, fuses are rated according to the power rating of the appliance. If you have to replace a fuse, it's essential, having checked and corrected the reason for the fuse blowing, to replace it only with another of the same rating. A common UK plug is generally fitted with a 3A or 13A fuse.

Plugs for appliances rated up to about 700 watts should have a 3-amp fuse (coloured red). 

For example:

  • 3A Fuse – Table lamp, standard lamp, television, video, computer, mixer, blender, fridge, freezer, power drill, jig saw, soldering iron.

Plugs for appliances rated between about 700 watts and 3000 watts (the maximum rating of a wall socket) should be fitted with a 13-amp fuse (coloured brown).

For example:

  • 13A Fuse – Washing machine, dishwasher, microwave, kettle, toaster, iron.

Manufacturers have now standardised plug fuse ratings to be either 3A or 13A. However, 5 Amp fuses are still used in some older equipment and are available to buy.

UK plug pin gauge

We have developed a plug pin gauge which allows you to perform some quick checks to help identify a sub-standard or counterfeit plug.