Boat fire safety

Whether it’s at marinas, canals, lakes, coastal inlets, harbours and quaysides, motorised boats present a potential risk of fire, explosion and CO poisoning incidents.


Fire and CO risk on boats

Identified risk

Many fires and carbon monoxide incidents happen because of human error, poor installation of equipment/appliances and on occasion, dangerous practices by boaters.

Many people do not appreciate the risks associated with boats and their domestic equipment and installations. Even a moderate sized boat can carry hundreds of litres of diesel, tens of kilograms of Liquefied Petroleum Gas (LPG) and 20-50 litres of petrol. These fuels are combined with readily combustible materials such as wood and fibre/glass-reinforced-plastic and they are all placed in close proximity to sources of heat and ignition such as engines or appliances, 12 or 24V DC and 240V AC electrics and solid fuel stoves.

Due to the fuels, boat construction and the nature of moorings, fire can easily spread to, and damage, neighbouring crafts, adjacent jetties and nearby properties.

Electrical issues

Flawed installations, poor maintenance, inappropriate appliances or incorrect use are the root of many incidents - especially in an environment with vibrations, flexing, humidity, high and low temperatures, cramped spaces, water and in many cases salt exposure – electrical systems and installations face a lot of stress compared with the same sort of electrical needs in buildings. Boat owners need to keep their eyes, ears and noses alert and deal with any problems immediately.


The BSS urges owners to keep their boats well maintained and to keep alert to possible leaks, poor running engines and the strong smell of petrol. Based on BSS advice for boaters provided in 2022:

Escaping vapour will sink to the lowest level of its surroundings. It builds-up at low level in places such as cabin floors, lockers, bilges and other ‘still-air’ spaces.

Even if the concentration of vapour is too rich to ignite immediately, it will dilute creating the potential for a serious fire and/or an explosion, even though, given enough ventilation, it may dissipate to a safe level eventually.

These are ten petrol safety essentials that will help keep you and your crew safe:

1. Before starting out, use all senses to check the fuel system and engine for petrol leaks or any signs of damage or deterioration. Have any problems sorted out first.

2. Do not switch on the electrical supply or turn the ignition key if there’s a strong smell of petrol. Stop immediately if there’s a strong smell of petrol after you start.

3. Keep vapour out of the boat! Before refuelling, close all windows, hatches, doors and awnings; also turn off all cooking appliances and any other ignition sources.

4. Double check before you start pouring, that you are using the correct filling point.

5. Afterwards, clean up any spills straight away. Be sure to re-secure the filler cap.

6. Avoid decanting petrol from containers, but if you must, use anti-spill containers, spouts or nozzles to allow, clean and easy, no-spill refuelling.

7. Don’t carry spare fuel, unless it is needed and then it must be in cans

specifically designed for petrol. Always keep within the legal capacity limits.

8. Containers should never be filled completely and must be stowed securely upright, away from intense heat and out of direct sunlight to prevent pressurisation.

9. Refuel any portable engine or tank ashore and safely away from any sources of ignition. Always follow marina / mooring rules on petrol refuelling and handling.

10. Never use any bowl, bucket or other open container to carry or transfer petrol or mix in 2-stroke oil.

For more information, click here.

Solid fuel stoves

Solid fuel stoves continue to be a significant cause of fire on inland waterway boats. These heaters are very popular on narrowboats, coastal barges and on some classic and vintage yachts or ex-fishing boats.

The Boat Safety Scheme highlights six risks that must be avoided or managed, if boaters and crews are to keep safe with solid fuel stoves:

  •  A lack of crew appreciation or vigilance, combined with poor appliance air inlet control, leading to 'over-firing' of the stove causing a boat fire

  • CO poisoning due to the escape of stove flue gases into the cabin

  • Items and materials being too close and getting too hot for too long

  • Running stoves with doors open (forgetfulness, naivety, broken catches, falling asleep)

  • Poor maintenance and misuse of the stove leading to a chimney fire

  • Poor stowage of hot/cooling ash and embers, either in the cabin or in unprotected areas of risk on decks (near flammable objects, near cabin ventilators, on combustible surfaces, etc)

Information explaining how to avoid these risks is available here.

Liquified Petroleum Gas (LPG)

Fixed gas systems must be installed to accepted boat installation standards and in accordance with the appliance manufacturer’s instructions. Gas appliances and flues should be routinely serviced and maintained.

The BSS encourages owners not to allow any bodge jobs! It says always use a competent person to carry out work on LPG systems. Ask a local boatyard or contact the Gas Safe Register for details.

In addition:

  • Make sure gas canisters, bottles or cylinders are stored upright and where any leaking gas will flow overboard and not into the interior of the craft. Preferably, this will be in a suitable, vapour-tight, self-draining locker.

  • Check flexible hoses for damage or deterioration. If you’re in any doubt about their good condition, get them professionally checked and renewed.

  • Check your LPG system for leakage by routine observation of a bubble tester installed in the cylinder locker, or by testing all joints with leak detection fluid.

Portable camping-style equipment

Owners of boats without proper galley facilities are recommended to consider using a flask for hot drinks when aboard as portable camping equipment is not suitable.

Following explosions, fires and CO incidents in boats, caravans and other enclosed spaces, boaters should heed any instructions for portable gas equipment that states it should only be used outdoors.

Unless any portable gas equipment is specifically designed for boat use, then it should only be used ashore. And whatever else happens, fuel canisters should always be changed away from the boat and away from ignition sources. Equipment and canisters should be stowed in a self-draining gas locker, or on open deck where any escaping gas can flow overboard.

Carbon Monoxide

If you are smelling and breathing in petrol-engine exhaust fumes, stop the engine and get off the boat.

  • Know the symptoms of CO poisoning, if anyone is indicating they are suffering, get them medical help. If the symptoms are severe – call the emergency services.

  • As a belt and braces defence, install a CO alarm certified to the BS EN 50291-2 standard, test it routinely and never remove the batteries

There is a potential for exhaust and flue gasses to be drawn into a boat from a neighbouring boat, through open doors, windows and fixed ventilators. A suitable CO alarm is the only protection against this possibility.

While at higher levels it can kill, CO is still a danger at lower concentrations as it can cause chronic illness affecting physical and mental health.

This poison gas has multiple potential sources on boats including all fuel-burning appliances, flues, chimneys, engines and exhausts. It is the by-product of an incomplete combustion of carbon-based appliance and engine fuels – such as gas, LPG, coal, wood, paraffin, oil, petrol and diesel.

So staying safe begins with installing all such equipment properly, in the way the maker describes. The continued safe enjoyment of boats will endure if maintenance doesn’t drift, or repairs are not put-off and equipment operational instructions are followed.

It’s also crucial for continued safety that everyone aboard understands the risks and knows the danger signs; they must always be watchful.

For more tips and advice to help you and your crew stay safe, click here.

CO alarms are now mandatory on most boats on the inland waterways subject to the BSS requirements; more details are available following the above link.

Alarms Save Lives

Smoke alarms

Follow the alarm makers instructions for fitting and where these are not specific for boats, the advice is that alarms should be mounted on the deckhead (ceiling), 30cm from the cabin sides and within five metres of each protected area of the vessel. On some boats this will mean installing more than one alarm, and it is recommended to choose units that can be linked together.

Guidelines produced by BSS on smoke alarms in boats can be found here, including a list of models recommended for boats by the manufacturers.

Carbon monoxide alarms

For boats with fuel burning appliances, an engine or generator aboard, the strong recommendation is to fit a suitable audible carbon monoxide alarm for an added re-assurance. 'Black-spot' colour-changing indicator cards are not good enough. Boaters will not have an instant warning of dangerous CO levels and there's no alarm to wake up anyone asleep. The BSS advice is to fit alarms that meet BS EN 50291-2; these are best suited for boats, choose only those with a BSi or LPCB certification mark. (see )

For the best protection, follow the alarm manufacturer's installation instructions as far as the space and nature of the boat allow. But if the placement directions are difficult to meet on any boat, these are the 'best practice' points. Try to place the alarm:

  • in living quarters between 1m and 3m (on plan view) from the appliance

  • keep alarms from being directly above a source of heat or steam

  • if wall mounting an alarm, fix it high up, but at least 150mm from the ceiling and where the indicator lights can be seen

  • if ceiling mounting, fix alarms at least 300mm from the cabin sides and bulkheads

  • in sleeping quarters have the alarm in the "breathing zone", i.e., near the bed head

  • before fixing, test that the alarm can be heard from any position in the boat (or buy further alarm(s))