December 18, 2014

Check your sockets!

Are you making sure that all of your office electrical points are fit for purpose? Because you should – in reality, infrequent PAT tests simply won’t cut it.

’13 amp plug tops’ are in every day use and should be safe to use they also form part of the portable appliance testing (PAT) procedure. The 13 amp plug top must be inspected and fuse rating correct for the appliance load.

British power sockets are fully regulated by the UK government.

The BS 1363A standard for 13 Amp plugs, sockets and adaptors is required by “The Plugs and Sockets etc.  (Safety) Regulations 1994”.

Socket outlets (13amp)  must  be safe  and  include  internal  shutters  to prevent  children  from  poking  objects into them. (BS 1363 was introduced in 1947!)

BS 1363 starts by specifying the dimensions of the 13 Amp plug top, and then specifies the requirements for sockets to be both safe and work properly with all 13 Amp plug tops.

It is essential that only 13amp plug tops of the correct dimensions are ever inserted into sockets.

It is dangerous to;

  • try and insert or force a plug top into a socket outlet or use a plug top without an earth pin in place;
  • push the earth shutter down to insert wires in the socket out let;
  • try to insert wires with the plug top in to a socket outlet ;
  • use other items as the protective fuse;
  • use a larger fuse then the appliance recommendation;
  • use a plug top where the wiring is falling out of the grip holder;
  • the plug top is broken damaged in any way.
  • It  is  impossible  to  predict  how sockets  will  perform  when  incorrectly used or not to BS 1363  standard

Non Standard

Unfortunately there has been an increase in counterfeit substandard plugs imported in too the UK and available to purchase on the internet.  A common indicator of a counterfeit plug is an earth pin which is partially insulated.

NOTE: Plugs with partially sleeved earth pins are ALWAYS counterfeit, and are not allowed to be sold, even for non-earthed applications.

Many of the imports have pins of incorrect size and shape, BS 1363 requires that all power pins (the shorter pins) are partially insulated.

For safety reasons:

  • The earth pin must be solid metal (although moulded plugs intended only for two wire applications may have a completely insulated pin). “Sleeves shall not be fitted to any earthling plug pin.”
  • Having a sleeve on an earth pin is dangerous because it can prevent there being any contact to the earth of the socket.  To ensure that the earth connection is made as soon as the plug touches the socket many sockets place the contact right at the faceplate, this means that continuity is lost as soon as a plug with a sleeved earth is fully inserted.
  • The partially insulated earth pin does not make contact with the earth part of the socket.
  • Lack of an effective earth leads to a seriously dangerous situation which could result in a fatal electric shock.

Chargers for mobile phones, games and other devices are often built into BS 1363 type plugs.  Such chargers need to conform to the pin dimensions of BS 1363 in the interests of safety, and also to ensure that BS 1363 sockets are not damaged by their use.  There are many instances of chargers which do not meet these expectations, especially when they are counterfeits.

Multy plug Adaptors

They enable more than one plug to be put into a single socket, or allow a plug or plugs which are of a foreign type to be used in a UK socket.  Adaptors sold for use in the UK is required to meet BS 1363-3; 1995, the specification for adaptors.

  • These adaptors MUST be shuttered, if they are for use with non-UK plugs then the adaptor MUST be fitted with a fuse, and they MUST conform to the pin dimensions of a BS 1363 plug.
  • The plug part of a typical travel adaptor can be misaligned and shorter than the real plug top as a result you can never be sure if such a device will be securely held in a socket, or if the device will damage the socket.
  • A non-standard device which works in one BS 1363 socket may be unsatisfactory  in  another socket of  slightly  different,  but  still  fully  compliant  design, and there are hundreds of slightly different sockets in use in Britain!
  • A typical 13 Amp socket the pin of a real plug fits into the socket, a pin which is thinner may not make proper contact and can overheat or arc.
  • A pin which is too fat can cause permanent damage to the contact so that subsequent use of a standard plug will overheat or arc.
  • Standards are created for a reason; BS 1363 ensures that plugs and sockets work together.

Multy plug Extension leads

There is a problem in BS 1363 which allows extension sockets to be manufactured with the earth hole placed too close to the edge.  Most multi-way portable socket outlets exploit this loophole and permit the insertion of an inverted plug into the earth pin only, thus opening the shutters of the current carrying contacts.  This is a clear danger for the user.

It is to be hoped that this oversight will be corrected at the next revision of BS 1363.  Until then it is important to ensure that children are not allowed access to this type of extension .and where they are identified removed from service where this is not possible ensure that they are used correctly

Plug-in Socket Covers Are Dangerous!

The so-called “safety socket cover” usually takes  the form of a dummy 13A plug, but real plugs must be made to a very precise size, and sockets are made to fit them.  No socket cover is the right size!  Putting the wrong size and shape object into a socket causes a number of problems, including permanent socket damage:

“Socket-outlets to BS 1363 are the safest in the world Socket protectors are not regulated for safety; therefore, using a non-standard system to protect a long established safe system is not sensible.”

Unlike real plugs, the various design faults of socket covers allow a curious child to insert them (upside down) into the earth pin only.  Children like to play with socket covers – plugging in upside down opens the shutter and expose live contact and allows children access to the live contacts!

  • Normally it is quite difficult to find an object which will do that, and stay in place.
  • Socket contact damage -results in overheating and possible fire.
  • Socket shutter damage – the shutters will not be able to protect children .
  • Some socket covers make it possible to poke pins and paper clips into the live parts!
  • Broken plastic pins suck in the earth hole – prevents shutters from closing
  • Wrong size pins can make covers easy to remove, some even pop out by themselves!

If you need professional safety advice, contact us anytime.

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About the author

Eamon Griffin