Non-Sleeved Plugs

In 1984, BS 1363 was amended to require insulation sleeves on the line and neutral pins. More than 30 years later, equipment fitted with non-sleeved plugs is still found in use. What should be done if a non-sleeved plug is found during a PAT inspection?

Plugs sold in the UK have been covered by statutory legislation since 1987, which requires them to meet the BS 1363 British Standard. However, the legislation is not retrospective, so it does not apply to older plugs already in use. There is no requirement to replace non-sleeved plugs purely because they are non-sleeved.

In Summary

• Older non-sleeved plugs can remain in service if in good condition.
• Inspect carefully and replace if there is any damage or doubt.
• Replace when equipment is supplied as part of a business activity, such as hire, resale, or rental accommodation.

Why do Plug Pins have Insulation Sleeves?

The insulation sleeves on the line and neutral pins reduce the risk of electric shock if a plug is partially inserted or withdrawn from a socket. Without sleeves, it can be possible to touch the metal part of a live pin while the plug is still making contact inside the socket.

This is especially worth considering in areas accessible to children. Smaller fingers can more easily reach the gap around a partially inserted plug, increasing the risk of contact with an exposed live pin.

Sleeving also reduces the chance of a metal object making contact with a live pin if the plug is not fully inserted. This change was introduced to improve safety in normal use, particularly where plugs are frequently plugged in and unplugged.

For more background on BS 1363 and why the sleeved pins were introduced, see this IET guide: The remarkable evolution of BS 1363.

When to Replace a Non-Sleeved Plug

Although older non-sleeved plugs are not automatically a fail in a PAT inspection, many organisations choose to replace them as a sensible safety upgrade where practical. This is particularly recommended in areas accessible to children, or anywhere plugs are handled frequently.

If a non-sleeved plug is left in service, bear in mind it will usually be at least 30 years old. There is a good chance it will have suffered some damage in its lifetime. Inspect it carefully for cracks, heat damage, loose parts, or bent pins. If in any doubt, replace it.

Non-sleeved plugs must be replaced on equipment that is hired out, on second-hand electrical equipment offered for sale, or on appliances supplied in rented accommodation. This equipment is covered by the Plugs & Sockets etc. (Safety) Regulations 1994, which apply to electrical equipment supplied in the course of a business.

If a Plug is Replaced

If a non-sleeved plug is replaced, make sure the new plug is a BS 1363 plug from a reputable source, the correct fuse is fitted, the cord grip is tightened on the outer sheath, and the conductors are terminated correctly. A poor plug replacement can be more dangerous than leaving an older plug in service. If you need a refresher, see our guide to wiring a plug.

Recording Non-Sleeved Plugs on PAT Test Records

If a non-sleeved plug is in good condition and the equipment is not being supplied as part of a business activity (hire, resale or rental accommodation), it is best practice to record an advisory note on the inspection and test records, with replacement recommended where practical, especially in higher-risk environments.

Dangerous Counterfeit Plugs with Sleeved Earth Pins

It is also worth looking out for plugs with sleeving on the earth pin. This should not be confused with the plastic ISOD (Insulated Shutter Opening Device) found on some Class II appliances. In the example shown, a counterfeit plug is connected to a three-core Class I cord set. The sleeve can prevent the earth pin from making contact in the socket, meaning the appliance may not be earthed. These types of plugs are regularly found during PAT inspections and are still widely sold on sites like eBay.

If a plug looks unusually new but has non-sleeved pins, treat it with suspicion, as it may be substandard or counterfeit.

Identifying counterfeit and substandard electrical equipment is an important part of the visual inspection process. We have more examples and guidance here: counterfeit electrical equipment.