• Plug and sockets on the generator or mains supply should comply with BS4343 to protect the connections from the weather and natural hazards.
  • Provide enough socket outlets – overloading socket outlets by using adaptors can cause fires.

Provide safe and suitable equipment

  • The use of double insulated (class II) portable appliances is encouraged because they do not include metallic parts which can become live in the event of certain faults. These are often marked with a ‘double-square’ symbol.
  • Choose equipment that is suitable for its working environment.
  • Use proper connectors or cable couplers to join lengths of cable-taped joints are not acceptable.
  • The supply cables to equipment should be of a flexible type, not rigid core, to avoid damage to the conductors.
  • The ends of flexible cables should have the outer insulation sheath of the cable firmly clamped to stop the wires (particularly the earth) being pulled out.

Reduce the voltage

One of the best ways of reducing the risk of electric shock accidents is to limit the supply voltage eg using 110V or lower equipment. Some fridges for example will operate on a 12V supply.

Provide a safety device

Mobile catering units connected to the mains supply should be protected with an RCD (residual current device) having an operating current of 30mA and a disconnecting time of 40mS at an operating current of 150mA. Earth continuity throughout the supply installation is essential.

RCDs include a test button that should be operated each day prior to trading. If the RCD 'trips' it is a sign of a fault and you should consult a competent person immediately and have the electrical installation checked before using it again.

8.2 Carry out preventative maintenance

All electrical systems, including portable appliances (eg a kettle), transportable appliances (eg a cooker) and fixed installations (fuse boxes, cabling, spur outlets, etc.) must be properly maintained by a competent person. Although it is for you to decide how to maintain electrical systems, it is strongly recommended that a planned maintenance programme is formulated and implemented. A suitable programme would include the following elements:

Fixed installation

  • The fixed installation should be examined and tested periodically by a competent person. The competent person will advise on the frequency of further examinations and tests.

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