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Dangers and Correct Usage of Extension Leads

We get asked a lot by new clients “Do extension leads cause fire”?

This article addresses the right and wrong way to use them in your office


Electrical Installations – wall sockets, floor boxes and extension leads are part of a standard office setup. However, when is it a good idea to use an extension lead and when is it not.

Do extension leads cause fire? What are the correct safety procedures? What are the dangers?

Some problems that can be experienced with extension leads can be as follows

  1. When an extension lead is not contained within desks. In addition if they are laying across access routes they can cause a dangerous trip hazard
  2. If being continually walked on and pulled by catching chairs and feet. This causes the cable to become damaged. Furthermore the cable sheath becomes damaged and exposed to electrical shock
  3. Plugging one extension lead into another to create more sockets. This can cause the current to be exceeded and cause a possibly fire hazard
  4. Using an extension lead in the coiled position can cause a fire hazard

Best practice when installing extension leads

  1. Only use manufacturer assembled extension leads and plug one lead into a dedicated socket or floor box.
  2. Use surge protected extension leads
  3. Use the correct rated extension lead for your application and equipment used
  4. Install the extension lead so none of the lead is on the floor or exposed to tripping, catching or damaged. (i.e. via containment in desks, cable spines from floor boxes)
  5. Install additional wall / floor electrical sockets if you are overloading your existing sockets with large extension leads or joining them together

If you have any concerns with your electrical installation please call for free advice or a survey on 01923 888588 or [email protected]

NM Cabling is a technology and structured cabling integrator working throughout the United Kingdom.

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