Chapter 41: Protection against electric shock

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This chapter is still based on BS EN 61140 which is the basic safety standard that applies to the protection of persons and livestock, but now introduces particular reference to protective equipotential bonding in relation to metallic and plastic pipes and telecommunication cables.

Regulation 411.3.1.2 introduces the word dangerous to emphasis the risk associated with protective equipotential bonding.

411.3.1.2 Protective equipotential bonding

In each consumer’s installation within a building, extraneous-conductive-parts liable to introduce a dangerous potential difference shall be connected to the main earthing terminal by protective bonding conductors complying with Chapter 54. Examples of extraneous-conductive-parts may include:

  1. metallic water installation pipes
  2. metallic gas installation pipes
  3. other metallic installation pipework and ducting
  4. central heating and air conditioning systems
  5. exposed metallic structural parts of the building.

NOTE: Where non-metallic pipes (e.g. plastic) enter a building and are then connected to metallic pipes within the building, the metallic pipes within the building do not normally require protective bonding as they are unlikely to be extraneous-conductive-parts.

Connection of a lightning protection system to the protective equipotential bonding shall be made in accordance with BS EN 62305.

Where an installation serves more than one building the above requirement shall be applied to each building.

Where an incoming telecommunication cable has a metallic sheath, equipotential bonding shall be applied. However, the consent of the owner or operator of the cable shall be obtained. Where consent is not granted, and as a consequence this requirement is not met, details shall be recorded in the description section of the appropriate electrical certification specified in Part 6.

411.3.3 Additional requirements for socket-outlets and for the supply of mobile equipment for use outdoors

411.3.3 (i) socket-outlets with a rated current not exceeding 32 A in locations where they are liable to be used by persons of capability BA1, BA3 or children (BA2, BA3)

For confirmation the external influences relating to capabilies of persons are:

BA1 – Ordinary,
BA2 – Children,
BA3 – Handicapped