Fire extinguishers ......I’m in need of education

DavidJ

DavidJ

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Following the recent posting “Disaster” by petem on fire extinguishers, I need some education.
I have a 2002 Sealine S37 in Spain with the original engine room seafire auto extinguishers with manual lever on the cockpit. They are in good condition with no corrosion and showing pressure still in the “green”.
I learn from petem’s posting that there is a Spanish 10 year life rule so I’m considerably over that.
Can I get them refilled with gas.? I assume from the age mine are gas.
I believe the current move is for powder but is this a requirement or just nice to have? Sounds mucky to me if they go off especially if the engines are still running. I have no auto shut off.
All knowledge most welcome.
Cheers
David
 
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DavidJ said:
I believe the current move is for powder but is this a requirement or just nice to have?
Click to expand...
For e/r, afaik the opposite is true: I've seen powder-based systems reconverted to gas, but never the other way round.
The two problems with powder being that it leaves a mess practically impossible to clean properly, and if it goes off with the engines running, even the small part that can be sucked inside the air filters can seriously damage the engines.
On top of that, the powder can pack up in the bottom of the bottle, which should be "shaked" on a regular basis (at least yearly, as I was told by a specialist when I asked about my old boat, which had powder extinguishers), to avoid the risk that only inert gas will be blown out whenever necessary.

Gas fire estinguishers (HFC227, aka FM200) are the best choice for e/r. Or at least they were, till two years ago.
For some reason, H&S gurus seem to enjoy changing the regulations in this field every other day... :ambivalence:
Whatever your bottle is filled in with should be indicated on it, anyhow.

That aside, do you really need to bother about any Spanish rule?
I would think that you should only comply with the regulations of the registration Country, possibly together with the requirements from your insurance, if any.
Not positive about that, though.
 
Sounds like it is "Seafire" system the extinguisher can be replaced but probably expensive. Not sure about refilling.
 
Not a Spanish rule I know of but it is a seafire requirement to test every 10 years. Mine was e1000

The snag is your insurance. If it is not serviced and it goes up in smoke you have a problem !
 
Make sure the safety pin on the little chain is removed on the manual release arm on the cylinder, otherwise you will pull the release in vain.
Around half the boats I have worked on had still the pin installed, this should be removed when the boat is commissioned, I’d urge all owners with manual release to check their installation.
 
spannerman said:
Make sure the safety pin on the little chain is removed on the manual release arm on the cylinder, otherwise you will pull the release in vain.
Around half the boats I have worked on had still the pin installed, this should be removed when the boat is commissioned, I’d urge all owners with manual release to check their installation.
Click to expand...

The safety pin was in place on my boat.

If the extinguisher is in as new cosmetic condition and the gauge shows acceptable pressure is there any reason an extinguisher would fail to operate regardless of its age?
 
Probably not but the issues is your insurers. Y asked for the purchase survey on mine which said it was out of date. I told them it would be corrected. As I recall they did not specifically ask.
 
If you want the fire out then HFC 227A is the best way to achieve this. FM200 is simply a trade name of its maker, Chemours (formally Du Pont). Gaseous fire suppressants work by pyrolising (burning) around the flame, forming an impenetrable barrier and thus depriving the fire of oxygen. Neither Dry powder, foam nor water will do this, although foam is the next best thing (AFFF). Once it has pyrolised it becomes very very nasty (hydrofluoric acid, phosgene, etc) and the fumes should not be breathed in, and the residues are a pain to clean off, although not as bad as burnt dry powder.

I like to have AFFF hand extinguishers to direct at a fire, and the water the foam is based upon also provides a cooling effect to prevent re-ignition. A gas drench system has the advantage it just needs to achieve a fairly low level concentration to form the oxygen barrier (~8%), but it won't provide any barrier cooling, despite it being a refrigerant.

The gas is from the HFC family of refrigerants. So what ? It behaves like a refrigerant changing from its liquid state to gaseous state subject to the temperature and pressure it is subject to. When it is filled in a cylinder on its own it will sit at its saturation (boiling) point as a mixture of liquid and gas.

So not only must the gauge be in the green, but its weight must also be checked periodically. If it leaks slowly the gauge will not move all the time there remains any liquified refrigerant, so weighing the bottle is important.

The gas does not deteriorate because it is a single molecule, so is not subject to chemical degradation, unless somehow a contaminant were to enter the cylinder, and unlike a blended gas such as R407C cannot suffer partial loss of one component.

Not sure what to say about the rules apart from rules are rules, especially when they exist to satisfy some nonsense or other under the generic banner of "Health & Safety". If it is an EU rule you can ignore it, because they no longer apply to this Country (I'll get my coat !). Changing the gas would be a nonsense as this would simply be exchanging one lot of the gas for another. I expect a separate rule exists to prevent cylinders ageing unduly, or becoming degraded by corrosion, etc.
 
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Thanks all
It appears that my only concern is the insurance aspect.
The thought of exchanging one lot of gas for another to satisfy some untested insurance criteria seems not only environmentally unfriendly but financial nonsense re superheat6k’s comment.
I will consider doing a weight check but worried about maybe setting the thing off.
Great explanation by superheat6k.
I guess I’m a bit stuck for what to do next except for checking the pin outlined by spannerman.
Thanks again
David
 
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Check the gauge each time you do routine engine bay inspections.
The gauge may read slightly low in cold temperatures this is normal.
 
A periodic and documented inspection say once each year might satisfy an insurance company, except that may require such an inspection by a suitably qualified expert. I suppose this would become a point of discussion if the boat caught fire and the fire wasn't adequately extinguished, but that said I'm not sure surveyors pay too much attention to the overall fire fighting capability on most boats, just are there fire extinguishers.

On my boat I have two medium size automatic HFC 227a extinguishers in the engine bay, a third in a large fwd compartment where the fuel pre filters reside, then a dry powder above the galley next to a fire blanket, plus two 1 litre AFFF hand held either end of the main cabin. All are kept clean and dry.

I have also installed fuel shut off valves with remote cable pull to close them in an emergency. Whereas these would be very effective in an engine bay fire situation, they have been something of a PITA when I have accidentally caught the cable when rummaging in the locker. Last week I thought my stbd engine refusal to start nightmare had returned, only to later find the isolation ball valve almost fully shut !

Also with dry powder periodically the bottle should be shaken vigorously to loosen the powder.

I am tempted to ask my insurance broker what they would expect is reasonable in regard to fire extinguisher inspection and / or replacement, but doing so might create more questions than answers. I guess a bit like Gas Safe inspections - not sure too many of us have had our gas installations regularly checked by a registered engineer who is specifically qualified for LPG installations.

I did ask them about my recent install of a Chinaspacher heater and they were fine with that as long as it was installed by an engineer, which it was.
 
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superheat6k said:
On my boat I have two medium size automatic HFC 227a extinguishers in the engine bay
Click to expand...

Is that two for backup, or because they only cover the rated volume when added together? If the latter, be aware the manufacturers say not to do that (assuming simple standalone extinguishers). The reasoning is that they’re unlikely to go off at the same moment, the first going off and knocking the fire back a bit will delay the second until the fire has returned to full strength, and neither one going off alone is enough to actually put the fire out. An auto system has to be able to discharge all the medium in one go, which means either a single big extinguisher or an interlinked system.

Pete
 
David,

The drivers for checking my Fire extinguisher system were

1) the alleged Spanish regulations (although this may not be relevant for a UK flagged boat)
2) a recommendation from my orginal survey "The engine room Seafire system should be serviced / inspected by the manufacturer’s agents."
3) piece of mind
4) the exclusion in my 'Y' Insurance policy:

You are not covered from fire or explosion on the Vessel where the Maximum Designed Speed of the Vessel under motor exceeds 17 knots if fitted with inboard Machinery, unless:

(a) the Vessel is equipped in the engine room with a fire extinguishing system automatically operated; or
(b) has controls at the steering position; or
(c) controls next to the engine room; and
(d) all properly installed and maintained.


I also believed from others experience that the inspection / test would be a simple / cheap task (i.e. visual inspection plus perhaps a weight check).

My boat was built in 2002 and had the original FM200 extinguishers. There's lots of info on the web concerning this as:

https://www.firesuppression.co.uk/fm200-gas.aspx
http://www.autoproltd.co.uk/fm200-fire-extinguishing-system.html
https://www.chemours.com/FE/en_US/products/FM200_faq.html

The main thing to note is that FM200 is clean and safe. The accidental discharge did no damage whatsoever (to me or the boat)! I also believe they are safe even after they have distinguished a fire.

If you still have halon on board then these should definitely be changed (I think they're no illegal), likewise if you have powder that will make a hell of a mess if discharged.

If you have FM200 (aka HFC227) then I would speak to the manufacturer / agent to ascertain what constitutes "proper maintenance". Do not speak to your insurer as they are not fire extinguisher experts.

Regarding hand held extinguishers, if these are old, chuck them in the skip and buy new ones. Some people discharge them into a bin so that they are no longer pressurised (might save the bin man a shock).

I hope this helps!

Pete
 
prv said:
Is that two for backup, or because they only cover the rated volume when added together? If the latter, be aware the manufacturers say not to do that (assuming simple standalone extinguishers). The reasoning is that they’re unlikely to go off at the same moment, the first going off and knocking the fire back a bit will delay the second until the fire has returned to full strength, and neither one going off alone is enough to actually put the fire out. An auto system has to be able to discharge all the medium in one go, which means either a single big extinguisher or an interlinked system.

Pete
Click to expand...
Purely as back up. I acquired a spare and felt it better placed somewhere useful than in my come in handy cupboard.
 
Cylinders can be refilled unless they are disposable and they have to be tested every 10 years, and this is a pressure test to demonstrate the integrity of the cylinder, once tested it will be stamped on the cylinder on the thick plate usually located at the neck area of the cylinder. It is illegal to fill an untested cylinder and no reputable refilling agent will do this, the refilling date is usually on a plastic tag around the neck of the bottle; most cylinders are rented and the owner will test them as part of the rental fee.
 
Assassin said:
Cylinders can be refilled unless they are disposable and they have to be tested every 10 years, and this is a pressure test to demonstrate the integrity of the cylinder, once tested it will be stamped on the cylinder on the thick plate usually located at the neck area of the cylinder. It is illegal to fill an untested cylinder and no reputable refilling agent will do this, the refilling date is usually on a plastic tag around the neck of the bottle; most cylinders are rented and the owner will test them as part of the rental fee.
Click to expand...
And this applies to fire extinguisher cylinders sitting ~ 4 - 5 bar, rather than high pressure gas cylinders at 200 - 300 Bar ? Are you sure ?
 
superheat6k said:
And this applies to fire extinguisher cylinders sitting ~ 4 - 5 bar, rather than high pressure gas cylinders at 200 - 300 Bar ? Are you sure ?
Click to expand...

He's talking about oxy acetylene bottles etc that are owned by BOC......nothing to do with privately owned fire extinguisher systems on a boat that are totally different!!! :rolleyes:
 
Ownership is irrelevant, if it is a high pressure cylinder conforming to BS or EU standards it has to be tested every 10 years, and Mr B is correct about oxy acetylene cylinders as these are just two of the many types of high pressure cylinders which need testing and it is the responsibility of the owner to undertake the testing irrespective of who actually owns the cylinder.

Most high pressure cylinders are rented and these include those used in fire fighting systems among many other systems, so the most important questions are:

Is the cylinder rented or bought outright?
Who is the lawful owner?

Is it a disposable cylinder or is it a refillable cylinder?

In the case of welding gases it would generally be BOC or Air Products (both owned by Linde Group) who own the cylinders and they are rented to the end user, similarly with rent free bottles it is the company who owns them and people pay a one off deposit and then swap the bottle for a full one and pay for the gas. Many smaller shops also have disposable cylinders and helium for balloons is an example of one where you buy the bottle and its contents, and when its empty it is disposed of as scrap metal.
 
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