Marine | Boatyard

ollowing on from the article regarding fire on board we discuss what the main causes of fire on a boat are:

It may surprise members to know that, in one three-year period, over half of the marine fire claims dealt with by Club Marine in Australia were caused by electrical problems.

Electrical wiring does not, unfortunately, last forever in a marine environment, especially if household wiring has been used in the build of the boat. Think cheaply made boats. Marine rated cable is more expensive, as it may be tinned wire, will have a higher fire rated insulation, and is only used by quality boat builders. Household wiring in a boat, subject to sea air, corrodes and you will see this as the copper cables turn black and the terminals corrode.

1 Corrosion can occur when connections are not protected with heat shrink or sealant. 2 Wire nuts or tape joints can fail, causing arcing and shock hazards. 3 All connectors should be crimp-on type, preferably with attached heat-shrink tubing to prevent moisture entry and corrosion. 4 Unsupported wires and cables can result in broken connectors and intermittent problems. 5 Solid copper wire can break, resulting in arcing and possibly fire. 6 Corroded cable, bad or corroded connections, corroded battery terminals or damaged cables can all heat up or cause a short circuit and possibly catch fire. 7 DIY installations are also prone to problems so if you are not an electrically competent person please do not attempt to do your own wiring. To mitigate the risk of electrical fires it is good practice to shut off all battery switches when leaving the boat. Bilge pumps should be wired direct to the battery, or supply side of the battery switch, and must be fitted with a correctly rated fuse ! Older installations should be checked out by a marine electrician to ensure that they are in good condition, especially if wiring is not secured and particularly if corrosion or water ingress is evident. shore power connection ensure that it is watertight, especially if the shore power is left switched on. Most cables and connections are rated at 50 amps however the shore power from the marina is rated at 63 amps.

Batteries, even sealed batteries which have a relief valve to release gas when they overcharge, give off an explosive gas, hydrogen, when charging. Accidentally shorting the battery can result in fires, or even explosion, so keep the batteries covered and the terminals clean. When checking batteries always wear glasses and gloves.

Fuel is also a source of fires on boats, especially when refuelling. Fuel lines to engines and generators should be checked regularly. Even diesel from a broken line spraying on to a hot engine or exhaust will catch fire. While diesel fumes will not catch fire easily petrol will, so all petrol should be kept in metal or specifically manufactured plastic cans. These should be stored on deck or a locker vented to the outside of the boat, never inside the boat. Petrol vapour is heavier than air, tends to accumulate in the lower sections of a boat and can be difficult to detect. Your nose is the best detector.

Likewise cooking gas is a particular hazard, especially because it is heavier than air and will gather in the bilge. A remote shut off valve should always be fitted on the gas line. Notices should be fitted above gas appliances to remind users to turn off the gas supply when they are not in use. Flexible gas hose should be changed every five years maximum. In the end, it’s all about taking due care and paying attention to the basics. There is no such thing as shortcuts when it comes to fire prevention. You need to make sure that your boat is in good condition, that all the wiring and fuel systems are up to scratch and that, most importantly, your fire-fighting equipment is ready to go. You also need to think about what you need to do in the event of a fire and we will discuss this next month.

Safe Boating.

Burned shore power connection Corroded terminals