Go Boating– Stay safe
Avoiding Fire Afloat – Safe Use of LPG
LPG is a common and useful fuel used by boaters…… but if basic safety rules are abused, the consequences can be horrific. Every year escaping gas causes fires and explosions on boats that could have been avoided. This leaflet offers pointers, advice and a guide to the safe use and storage of LPG.
You may have Liquefied Petroleum Gas (LPG) onboard in the form of butane or propane, perhaps in interchangeable blue or red cylinders. These are likely to be connected to a fixed system supplying, for example, a cooker and water heater. Or, you could be carrying disposable gas cartridges for a ‘camping’ stove. Some craft have fixed, refillable LPG tanks for gas burning engines. But whatever form of gas you have onboard, remember…
LPG can be a hazard. Here’s why…
… it is highly flammable and readily combines with air to form an explosive mix. If this explosive mix is exposed to a naked flame the resulting explosion may cause life threatening injuries and intense fire. Because they are watertight, boat hulls also act as good containers for escaped gas. LPG sinks in air and will spread into low level, enclosed spaces such as cabins, cockpits, engine and bilge areas. Even ‘small’ spaces such as cupboards or lockers can contain dangerous amounts of explosive vapour. LPG does not disperse easily from such spaces and so the cabin and hull can hold large volumes of the explosive gas/air mix without people being aware of any leaks. If this ignites, the situation could get worse, as a fire will readily flashback to the source of the leak. An LPG cylinder exposed to fire can be pressurised to the point where the pressure relief valve opens causing a dangerous jet of burning gas. Cylinders can also explode in the extreme heat of a fire and are known to throw debris far and wide
… comes from faulty burners, blocked flues and insufficient ventilation leading to carbon monoxide poisoning. Read the companion Guide Carbon Monoxide for advice.
Leaks or accidental gas escapes can be dangerous
They can occur due to equipment failure, by hob burners being blown out, when changing cylinders or even by children playing with gas burner taps.
Gas suppliers add a harmless, but pungent chemical to LPG allowing many people to smell escaped gas in the air at very low concentrations, so alerting them to take early action to deal with the leak before it gets critical.
Prevention is better than cure
If possible, isolate cylinders by closing the cylinder valve whenever you are not using appliances, at night or whenever you leave the boat. Don't leave a hob burner unattended – a draught could extinguish the flame and the hob will fill your cabin with an explosive gas/air mix. Supervise children on boats closely. Don’t allow them to play with gas burner taps or cylinders.
Regular checks that will help keep you safe
Make sure any changes on your gas system meet the latest British Standards and are maintained to Boat Safety Scheme requirements; e.g. select replacement or new appliances that have flame supervision devices on all burners. Ensure new appliances and components are fitted in accordance with manufacturers' recommendations. Don’t use appliances that are not designed or intended for use in boats. Follow manufacturers’ recommendations in operating, maintaining and servicing appliances. Have your system checked-over regularly and replace regulators that are more than ten years old. Don't allow any bodge jobs! Only use components that are suitable for use with LPG and ALWAYS USE A COMPETENT PERSON TO CARRY OUT WORK ON YOUR LPG
Safety first – treat gas escapes seriously
When changing cylinders or if you suspect a leak!
• Stop the engine.
• Turn off all burner taps on cooking, heating and lighting
appliances and extinguish all other naked flames.
• Turn off ignition systems on all appliances.
• Don’t operate electric switches (apart from the above).
• Don’t smoke or allow anyone else nearby to smoke until the
area is safe from the threat of escaped gas.
• Don’t use your mobile phone – keep it in your pocket or bag
and never touch any of its buttons if you can smell gas.
Before changing LPG cylinders…
… check that the valves on the empty and full cylinders are
turned off. If you need to use a spanner, make sure it’s the
correct size for the connections. Remember to tighten firmly.
Once you have replaced the cylinder…
… refit the plastic safety cap or plug on the disconnected
… if a leak is suspected after changing a cylinder and opening
the valve, check the cylinder valve with ammonia-free soapy
water or leak detection fluid and watch for bubbles to detect
the leak. Never use a naked flame.
… if a leak at the cylinder cannot be stopped, move it to a safe
place in the open, well away from the boat, and ensure that
people in the area are warned of the danger. Call your supplier
and keep people safely away from the cylinder until it has either
stopped leaking or your supplier has made it safe.
If you detect or suspect a leak, don’t panic,
but follow the safety first points and then…
… try to get as much through-flow of fresh air as possible by opening doors, hatches and windows and raising deck boards. … tie up or anchor – keeping a safe distance from other craft. If possible get everyone off the vessel and warn other people in the immediate area. Try to inform the local harbour, navigation authority or moorings staff.
If you are in any doubt, call the fire brigade using a land-line or a mobile phone well away from the risk area.
Don't use the LPG system until it is checked and the cause of the leak rectified by a competent person.
And remember… … an ‘empty’ cylinder may still contain some LPG vapour and is still potentially dangerous – treat it as if it were full.
… always ensure all cylinders, empty or full, spare or in use, are secured vertically on deck away from openings, or are in a drained cylinder locker.
… beware – ‘empty’ butane cartridges of portable camping appliances will still contain some gas – dispose of them in a safe place. They must never be discarded or stored within the vessel because gas will continue to seep out.
… using unsecured ‘camping’ style cooking, heating or lighting appliances in the cabin space is risky – why put yourself in danger?