Boat fire

[ShinyShoe]

I've got to admit that for gas fires unless the CO2 can isolate the fuel from the ignition source OR the oxygen supply it will be ineffective, but as our boats are normally pretty well enclosed spaces which are only open at the top, it would still be my first choice for any inboard fire simply because it is so much cleaner and won't cause much, or indeed any other damage.
I'm a Marine Engineer, and all of the Engine Rooms I have worked in are fitted with CO2 or similar flooding systems, designed to fill the space and exclude the air.

Their sealing and flooding systems are pretty sophisticated.
They also do a load of maths to know how much CO2 a sealed compartment needs to extinguish it.
You are looking at something like 30-70% CO2 to extinguish a fire. >5% is harmful to human health so you need to be able to deploy that in a way that you aren't breathing it.
Not sure on the volume of a typical cabin but lets call it 3m long, 1.75m high and 2.25m wide. So you have about 12cu.m.
You can't properly seal it because you have bilges spaces etc not designed to be completely sealed.
At 50% CO2, in 12m - if I understand correctly you would need about 12kg of CO2. A typical CO2 extinguisher in your home might be 2kg, a big workplace one 6kg.

All achievable in an engine compartment where you can have an extinguishing hole and otherwise a pretty sealed space. Where the risk of fire is high. Where the damage from the extinguisher may be more than the fire. Where you are outside on deck tacking it. For the cockpit? Where you can't even deploy the extinguisher till all heads are accounted for, where ever hatch and seal needs to be closed and a shed load of cylinder volume is needed... mmmm?

In the workplace you might well struggle to get approval to even a 2kg CO2 for use in the cabin... ...because you'll risk it being used directly.

One thing I haven't seen mentioned is the value of closing doors, windows, other entrances, and vents which can also smother a fire

On a steel ship this is quite effective. On a plastic boat - designed to be ventilated and make sure people sleeping don't suffocate, filled with lots of lovely soft furnishings and other combustibles. We've seen how things that we expect to be fire resistant (aka cladding on high rise buildings) once a fire is going are far from.

My work is very clear - extinguishers are provided because the law says they have to be. They don't expect me to use one. They expect me to get out and get others out. Anything bigger than a standard household kitchen bin size of fire - is considered too big for a standard extinguisher...

Fireblanket for the galley?

 

[colind3782]

I have lots of cheap Lidl type powder extinguishers on board so I'm never more than an arm's reach from one, an automatic gas extinguisher in the engine bay and a big one in the cockpit locker. I'd rather deal with the powder than have anyone trapped with no way to put out the fire.

 

[Pete7]

There is an alternative and that is AFFF a water foam extinguisher. Having spent a couple of weeks in a previous life using a variety of extinguishers, I now have a 3L and 1L AFFF on board in addition to a 2kg CO2 and the engine bay clean gas auto.

Having practised putting out a oil & kero fire in a 12 x 12ft drip tray with AFFF which was quite a fearsome fire, it proved impossible to relight the fire with burning oil because the foam acted as a barrier between the oil and the air.

One point worth looking at with extinguishers is how long they will last when used, most 1 - 1.5L extinguishers only last for 6 or 7 seconds hence choosing the bigger 3 litre AFFF.

 

[Sandy]

Hi Sandy,
I've got to admit that for gas fires unless the CO2 can isolate the fuel from the ignition source OR the oxygen supply it will be ineffective, but as our boats are normally pretty well enclosed spaces which are only open at the top, it would still be my first choice for any inboard fire simply because it is so much cleaner and won't cause much, or indeed any other damage.
I'm a Marine Engineer, and all of the Engine Rooms I have worked in are fitted with CO2 or similar flooding systems, designed to fill the space and exclude the air.
I'll also restate that an enclosed space which has been CO2 flooded MUST be ventilated once the fire is extinguished before re-entering the space.
Thanks for raising your points, made me think. ��
One thing I haven't seen mentioned is the value of closing doors, windows, other entrances, and vents which can also smother a fire pretty effectively. Again you need to be certain the fire is out completely before letting any air back in...

Hello Paul

I think you have hit the nail on the head, on a small vessel you can't block all the air vents! In a ships engine room you have far more control. Thinking about my wee boat on the transom I have four 10 cm diameter holes with venting to the engine, the sail locker hatch is not air tight and there are several holes into the engine compartment to allow various pipe work through. There is no way the companion way is airtight and I usually sail with two hatches under the sprayhood open to allow ventilation. I don't think engine fires are the main issue on a yacht it is the flammable material near them if things get very hot and the galley (back to butane or propane or whatever people use).

Many years ago I worked in buildings with Halon fire suppression systems, we knew we had seconds to get out of the room or get BA kit on if ever that went off, I was never happy working there.

 

[solent clown]

Halon and dodgy fire wire in armoured vehicles were some of the things back in the mists of time I had the pleasure to be involved in getting rid of. The flip side of so many extinguishers is they of course suppress combustion. Combustion is something we do ourselves in our own way...

 

[Corribee72]

Thank you everyone for the advice and comments, I am seriously considering the water mist extinguishers now, having been up close and personal to an uncontrolled fire, I have a whole new level of respect for it. The RNLI inspection is an excellent suggestion, many thanks for it. I hadn't seen the reports of the possible hazards relating to this style of stove before but having been at the sharp end, I can well believe them to be more common than you would think. I took the stove back to the retailer today, who logged an incident, withdrew the stove from the shelves and reported it up the food chain. Having seen what these things can do, I could easily imagine that someone could be seriously burnt or killed. We got lucky, still have a boat and have learned some serious lessons, just another day on the water I guess, although I hope we never have a day like it again, I must say. Thanks again to all.

 

[Pasarell]

Thanks for posting your experience and glad you are all OK following it. A salutary tale!
Thanks also for the discussion on extinguishers following, I will be taking a close look at type and positioning when I get back to my boat

 

[Pete7]

Always a worthwhile task. At home, in the car or at work, the saying "get out and stay out" applies but a bit tricky in the middle of Poole bay when you only went out for a day trip.

 

[vyv_cox]

Anyone tried one of these in anger? http://www.firetool.co.uk/je-50.html I saw a video of them in action at a show and was so impressed that I bought two of them. Seems they were developed for space capsules, suggesting they should be pretty good.

 

[Hoolie]

It seems to be implied but I can't see it stated anywhere, are these water mist extinguishers?

 

[vyv_cox]

It seems to be implied but I can't see it stated anywhere, are these water mist extinguishers?

I doubt it, not big enough. Mine are little larger than an aerosol.

 

[DownWest]

My only effort to kill off a fire was when an aircraft caught in our hanger. Rushed out with CO2 and we managed to control it. Just.. Volume was not a problem as the hanger was big. But it had 22 other aircraft in it and the one that was burning had full tanks. A few 'very interesting minutes'
I have been reading, for a while, that those camping stoves are not supposed to be used on boats. If that is so, why are they OK in tents?

 

[Sandy]

I have been reading, for a while, that those camping stoves are not supposed to be used on boats. If that is so, why are they OK in tents?

Tents "flash over" in about five seconds; at times inflicting horrendous burns. Boats take much longer to burn and running/walking away is difficult on water.