Krusty
Well-Known Member
Since the banning and disposal of Halon, what extinguishers do people use for an enclosed engine-bay? I need a neat unit for a space of about 8 cubic feet.
Fire extinguisher for engine bay
- Thread starter Krusty
- Start date
leadersail
Well-Known Member
I have found these to be the best value.
http://www.gaelforcemarine.co.uk/ProductDetailsPage.aspx?product_id=19566
1kg covers .............1.7m cube
1.5 ............. 2.5m
2 .............. 3.4m
http://www.gaelforcemarine.co.uk/ProductDetailsPage.aspx?product_id=19566
1kg covers .............1.7m cube
1.5 ............. 2.5m
2 .............. 3.4m
Roberto
Well-Known Member
are they water based ?
thanks
thanks
leadersail
Well-Known Member
They are GTFE gas . (FE36)
It is more powerful at extinguishing fire than FM2000 although they are a similar gas.
http://www.safety-marine.co.uk/downloads/Firemaster-GTFE-Extinguisher-Instruction-Sheet.pdf?did=25
I put hours of research into this topic and decided these extinguishers were the best for the engine space, the really good news is they are also a cheaper option than most.
Powder is the cheapest option but have disadvantages.
I then spent hours searching for the cheapest supplier.
It is more powerful at extinguishing fire than FM2000 although they are a similar gas.
http://www.safety-marine.co.uk/downloads/Firemaster-GTFE-Extinguisher-Instruction-Sheet.pdf?did=25
I put hours of research into this topic and decided these extinguishers were the best for the engine space, the really good news is they are also a cheaper option than most.
Powder is the cheapest option but have disadvantages.
I then spent hours searching for the cheapest supplier.
Roberto
Well-Known Member
thank you, I am convinced
after having had a small fire onboard this summer (quickly put out) I am investigating all means to fight fire from the very first onset /forums/images/graemlins/crazy.gif
I really do not want to have shaking legs during ten minutes another time /forums/images/graemlins/ooo.gif
after having had a small fire onboard this summer (quickly put out) I am investigating all means to fight fire from the very first onset /forums/images/graemlins/crazy.gif
I really do not want to have shaking legs during ten minutes another time /forums/images/graemlins/ooo.gif
Krusty
Well-Known Member
Thanks a lot for the information. I tkink you have resolved my problem.
ChrisE
Well-Known Member
Another vote for the product, we have had one (we are now onto no. 2) for 12 years and have had no false alarms but feel secure in the knowledge that they will keep us safe.
Roberto
Well-Known Member
Am I right in thinking that they basically work by filling the engine room with inert gas ? As I do not have the place to put one above the engine, I will have to put it to one corner of the locker, so about one half of the gas jet would be directed towards the two vertical sides, one half only towards the engine.. as it is gas then this should not matter too much, should it?
thank you again
r
thank you again
r
ChrisE
Well-Known Member
I'm no expert, but believe that they work by excluding air from the compartment by displacing it with the gas.
Mine sits above the engine and that seems reasonable in that if anything starts burning the flames and heat will rise melting the bulb that causes the extinguisher to start. If you can't put it above the engine, are you sure they are only about 8-10 cm wide?, then I'd guess that to the side as high as you can get would be a good second bet. BUT, as your well-being depends upon this I'd recommend talking to someone who understands the subject better than me.
Best of luck and glad that your fire didn't consume you!
Mine sits above the engine and that seems reasonable in that if anything starts burning the flames and heat will rise melting the bulb that causes the extinguisher to start. If you can't put it above the engine, are you sure they are only about 8-10 cm wide?, then I'd guess that to the side as high as you can get would be a good second bet. BUT, as your well-being depends upon this I'd recommend talking to someone who understands the subject better than me.
Best of luck and glad that your fire didn't consume you!
Roberto
Well-Known Member
[ QUOTE ]
If you can't put it above the engine, are you sure they are only about 8-10 cm wide?, then I'd guess that to the side as high as you can get would be a good second bet.
[/ QUOTE ]
Chris,
I read again the instruction sheet given above: at first I thought I read "mounted vertically", but they actually say an angle 15 to 90° is correct so basically they allow it to be almost horizontal, that s good I may find a tiny place somewhere /forums/images/graemlins/smile.gif
cheers r
If you can't put it above the engine, are you sure they are only about 8-10 cm wide?, then I'd guess that to the side as high as you can get would be a good second bet.
[/ QUOTE ]
Chris,
I read again the instruction sheet given above: at first I thought I read "mounted vertically", but they actually say an angle 15 to 90° is correct so basically they allow it to be almost horizontal, that s good I may find a tiny place somewhere /forums/images/graemlins/smile.gif
cheers r
alan8376
Well-Known Member
Not sure how one feels about experimenting???
If an extinguisher won't fit in the engine compartment. How about adapting the extinguisher, which can be mounted externally, at the point where the gas exits from the nozzle? (usually there is an existing pipe union!), and pipe it into the engine compartment using some formed copper pipe with holes drilled in it, converting it similar to a sprinkler system. Army 'Fighting Vehicles' make use of a similar system!
If an extinguisher won't fit in the engine compartment. How about adapting the extinguisher, which can be mounted externally, at the point where the gas exits from the nozzle? (usually there is an existing pipe union!), and pipe it into the engine compartment using some formed copper pipe with holes drilled in it, converting it similar to a sprinkler system. Army 'Fighting Vehicles' make use of a similar system!
Graham_Wright
Well-Known Member
It seems (perhaps naively) to me that, if the engine is running and taking its air for combustion from inside the engine compartment, whatever extinguishent is used, it will be sucked through the engine. In the case of powder I am told that this means "Goodbye engine".
If the air can be ducted directly to the engine air intake and cabable of being shut off remotely, any fire will kill itself by suffocation if there are no significant leaks (and there shouldn't be for sound exclusion reasons). Even if this doesn't work (and I am sure that wouldn't satisfy the insurer), it would certainly be no disadvantage.
Why does nobody advocate water? There is generally lots of it around.
The reason given by n RNLI safety adviser that "water and electricity don't mix" I think is invalid for 12v systems!
If the air can be ducted directly to the engine air intake and cabable of being shut off remotely, any fire will kill itself by suffocation if there are no significant leaks (and there shouldn't be for sound exclusion reasons). Even if this doesn't work (and I am sure that wouldn't satisfy the insurer), it would certainly be no disadvantage.
Why does nobody advocate water? There is generally lots of it around.
The reason given by n RNLI safety adviser that "water and electricity don't mix" I think is invalid for 12v systems!
alan8376
Well-Known Member
Of course in my extinguisher 'piping idea' Co2 would be ideal. Not only would it stop the engine safely, there would be no powder to possibly cause secondary problems!
Roberto
Well-Known Member
[ QUOTE ]
If the air can be ducted directly to the engine air intake and cabable of being shut off remotely, any fire will kill itself by suffocation if there are no significant leaks (and there shouldn't be for sound exclusion reasons). Even if this doesn't work (and I am sure that wouldn't satisfy the insurer), it would certainly be no disadvantage.
Why does nobody advocate water? There is generally lots of it around.
[/ QUOTE ]
Graham,
agree about powder.
The solution you advise of shutting down air inducts to the engine bay is indeed interesting, and requested by a few construction regulation authorities (ex; the french for commercially licensed boats, I don't know about UK MCGA code)
as for water, having two alternators + starting motor + solenoid inside the engine room, all heavy cabled to a 500Ah battery bank I am afraid water could cause a lot more damages..
If the air can be ducted directly to the engine air intake and cabable of being shut off remotely, any fire will kill itself by suffocation if there are no significant leaks (and there shouldn't be for sound exclusion reasons). Even if this doesn't work (and I am sure that wouldn't satisfy the insurer), it would certainly be no disadvantage.
Why does nobody advocate water? There is generally lots of it around.
[/ QUOTE ]
Graham,
agree about powder.
The solution you advise of shutting down air inducts to the engine bay is indeed interesting, and requested by a few construction regulation authorities (ex; the french for commercially licensed boats, I don't know about UK MCGA code)
as for water, having two alternators + starting motor + solenoid inside the engine room, all heavy cabled to a 500Ah battery bank I am afraid water could cause a lot more damages..
kenspratt
New Member
Ok Guys i'm sure you have all heard of the triangle of fire. I.e. Remove either Heat Fuel or Oxygen and the fire goes out. Now as someone suggests you can seal off the engine compartment and wait. The fire will extinguish itself in time as it burns up all the air. Technically this is true but if there is the slightest little bit of leakage in the air department then you can still have the fire burning away in a less than efficient manner which can result in a cautious boat owner gingerly lifting up his engine hatch to find that the fire was in fact sitting down there in the dark ready to say "Boo" or to give it its technical name causing a "back draft" kind of like in the film of the same name but without Kurt Russell being involved.
I will admit that is a bit on the extreme side of possibilities but never the less it would be very hard to extinguish the fire in such a way.
Now another way of at least slowing the growth of a fire is to remove the fuel. Now the only practical way to do this in a boat is to have fuel shut offs in easy to reach places.
The next method is removal of heat. Chucking water on a fire can do this but this only works well on class a fires as in things like wood and other solids. Anything involving Burning oils and adding water can sometimes just make it mad. (Unless you know what you are doing.) The resultant expansion of evaporating water can cause a splattering effect spreading the fire rapidly.
This leaves us with Powders and Halon (or rather Halon replacement). Powders are extremely good but as has been mentioned they leave a lot of mess. So the Gtfe1000 is probably the best method for remotely extinguishing a fire before it has had an opportunity to develop into a life threatening situation. These work by chemically inhibiting the propagation of fire. I.e. stopping the combustion reaction. This means they don’t need to expel every last piece of air. The disadvantage of the gas is that the engine can continue to run and the gas can be drawn in alongside the air drawing in more fresh air into the compartment putting you back to square one. So if a halon style extinguisher goes off you need to shut down your engine fairly quickly and so it is wise to have an audible alarm that sounds on activation or possibly even an auto engine shut down.
I will admit that is a bit on the extreme side of possibilities but never the less it would be very hard to extinguish the fire in such a way.
Now another way of at least slowing the growth of a fire is to remove the fuel. Now the only practical way to do this in a boat is to have fuel shut offs in easy to reach places.
The next method is removal of heat. Chucking water on a fire can do this but this only works well on class a fires as in things like wood and other solids. Anything involving Burning oils and adding water can sometimes just make it mad. (Unless you know what you are doing.) The resultant expansion of evaporating water can cause a splattering effect spreading the fire rapidly.
This leaves us with Powders and Halon (or rather Halon replacement). Powders are extremely good but as has been mentioned they leave a lot of mess. So the Gtfe1000 is probably the best method for remotely extinguishing a fire before it has had an opportunity to develop into a life threatening situation. These work by chemically inhibiting the propagation of fire. I.e. stopping the combustion reaction. This means they don’t need to expel every last piece of air. The disadvantage of the gas is that the engine can continue to run and the gas can be drawn in alongside the air drawing in more fresh air into the compartment putting you back to square one. So if a halon style extinguisher goes off you need to shut down your engine fairly quickly and so it is wise to have an audible alarm that sounds on activation or possibly even an auto engine shut down.
Pye_End
Well-Known Member
How long would an engine stay running once oxygen levels become low in an engine bay?
kenspratt
New Member
Not long if there is a way of isolating the air intakes. If not it might miss a beat or two while it sucks through all the Extinguishant but all the time it is pulling in gas it is creating a partial vacuum in the compartment and would subsequently draw in fresh Oxygen rich air from the outside world allowing the engine to continue running and eventually extracting the very material you want to put the fire out.
tcm
...
Re: Fire extinguisher for engine bay - removing oxygen
If you can seal (or even partly seal) the engine bay then the quickest way to get rid of the oxygen is to run the engine. With powder, of course, the engine would have to be on. But with engine on, the slightest bit of smoke from engine should be accompanied by putting the engine into neutral and holding high revs. You can extinguish car fires the same way - an ole citroen started wafting smoke through the dashboard and dropping into neutral and increasing revs a lot extinguished the fire.
If you can seal (or even partly seal) the engine bay then the quickest way to get rid of the oxygen is to run the engine. With powder, of course, the engine would have to be on. But with engine on, the slightest bit of smoke from engine should be accompanied by putting the engine into neutral and holding high revs. You can extinguish car fires the same way - an ole citroen started wafting smoke through the dashboard and dropping into neutral and increasing revs a lot extinguished the fire.
ChasB
Well-Known Member
Re: Fire extinguisher for engine bay - removing oxygen
Anyone got a link to a decent fire alarm?
Anyone got a link to a decent fire alarm?
ChasB
Well-Known Member
Re: Fire extinguisher for engine bay - removing oxygen
What about this scenario (as is the case in my boat)? I have two large engine compartments which are not isolated in terms of air flow. They measure 1.5 x 1.5 x 2 (there's a lot of other stuff down there) = 4.5. So that would be two units for each compartment?
Wrong. A fire starts. One extinguisher goes off and douses the fire a little, but not completely, air flows in from the other compartment and the fire increases. Eventually the second extinguisher goes off, and then the same thing happens. Meanwhile fresh air is still being sucked in. The fire rages on with nothing to stop it until the second engine compartment catches fire...
Clearly that's no good, so what should I do?
What about this scenario (as is the case in my boat)? I have two large engine compartments which are not isolated in terms of air flow. They measure 1.5 x 1.5 x 2 (there's a lot of other stuff down there) = 4.5. So that would be two units for each compartment?
Wrong. A fire starts. One extinguisher goes off and douses the fire a little, but not completely, air flows in from the other compartment and the fire increases. Eventually the second extinguisher goes off, and then the same thing happens. Meanwhile fresh air is still being sucked in. The fire rages on with nothing to stop it until the second engine compartment catches fire...
Clearly that's no good, so what should I do?
