What makes boats different from buildings?

Understanding how boats are different will help you know how to control the risks that electricity on boats can create.

What are the risks?
Just as in our homes, the use of 230 V electrical power on boats brings the risks that:

  • contact with live parts can cause electric shock and burns so serious they can be fatal, and
  • electrical overloading or faulty connections can cause fires.

Some of the key points that make keeping safe on a boat different from when you are in a building include:

  • Contact with water,
  • the exposure to severe weather,
  • vibration and rough usage, and
  • boats often have two or more sources of 230 V power.

Taking these points into account, more care needs to be taken with 230 V electricity on boats, including:

  • avoiding water coming into contact with electric equipment or wiring,
  • ensuring  the boat's different sources of electric power − shore power cables, engine‑driven alternators, inverters and installed or portable generators − are and never connected to each other or to the same wiring at any time (usually only possible due to careless or incompetent electrical work),
  • using shore power cables responsibly, and always ensuring that an effective earthing connection is made, via the cable, from the shore power socket to power inlet on the boat (and hence to the main earthing terminal of the boat's electrical system) when the cable is connected.

Making the right choice could save your life

In the era of modern, highly complex boat electrical systems, installing and maintaining safe systems is well beyond most boat users. So making the right choices is a boat owner's main way of keeping safe. The choices you make can make a safety difference, here's two to help keep you safe:

… choose to use a competent person to work on your boat's electrics

Use a competent person to design, install and maintain your boat's electrical systems and appliances, and to make any changes to them.

A competent person is someone having the necessary knowledge, skill and experience needed to avoid electrical dangers to themselves and others.

Seeking a BMET qualified fitter from a local boatyard will help with that choice.

… choose to have your boat's electrical system checked routinely

A boat's 230 V system can easily deteriorate in condition over time and use.

Have the fixed wiring, consumer unit (fuse/circuit-breaker box), switches, sockets and appliances checked by a competent person at least once every three years.

A competent person will help you be sure that:

  • the earthing and bonding is effective and your boat's electrical protective devices will work,
  • electrical circuits or equipment are not being overloaded,
  • any potential hidden electric shock risks or fire hazards are found and dealt with properly
  • only suitable appliances and equipment are used aboard
  • electrical appliances that have the British or European safety mark.
  • replacement appliances that are within the rated current load of the circuit.
  • replacement fuses or circuit-breakers of the correct type and rating.
  • you check your boat's electrical system as part of your boarding routine
  • Check consumer units, cables and connections, where they can be seen, for signs of mechanical and heat damage.