Fire extinguishers - are gauges any use?

mcframe

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My two 950g powder extinguishers have a best-before date a couple of years earlier than my christmas stilton - and even before my "spare" (not for use in France) flares.

I've also got a (newer) BFO 2kg one (transverse-mounted, so each tack shakes it up) with a gauge - is there any merit in getting a couple of smaller ones with gauges rather than the "chuck away after 5 years" toy car extinguishers?

I'm not coded, but I'm thinking that getting 'proper' ones that can be checked/serviced every ~8 years might be better than date-stamped ones.
 

planteater

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Last year I bought three 1Kg extinguishers with gauges. Two went to the boat and the third languished in the greenhouse where it got exposed to extremely high temperatures. When I finally got round to looking at it a couple of weeks ago the gauge read almost zero pressure. I set it off and the gauge was right - no pressure.

I'd rather trust the gauge than the date stamp.
 

chewi

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Last year I bought three 1Kg extinguishers with gauges. Two went to the boat and the third languished in the greenhouse where it got exposed to extremely high temperatures. When I finally got round to looking at it a couple of weeks ago the gauge read almost zero pressure. I set it off and the gauge was right - no pressure.

I'd rather trust the gauge than the date stamp.

+1
 

AntarcticPilot

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Just a thought - the crash test video made it pretty clear that the cure offered by a powder extinguisher was nearly as bad as the problem it solved, in terms of damage to textiles, equipment and so on. Are there other types more suited to the environment of a boat that will not trash everything when they are set off? I am even given to understand that a powder extinguisher could seriously damage a diesel engine, if let off when it is running.
 

westernman

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I used a foam fire extinguisher when my engine's starter motor went up in flames.

It did the job with no mess.

My fire extinguishers have gauges. I cannot find any dates anywhere on them.
I am relying on the gauges.
 

stownsend

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With dry power extinguishers, anorther check is every so often turn them upside down and listen, if you can hear the power move its not congealed.

Cheers

Stu
 

stownsend

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Forgot to mention the gauge is there to tell you the pressure, if its in the green there is sufficient pressure to expel the substance inside.

Cheers

Stu
 

BERT T

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Fire,Fire,Fire

Foam, or Aqueous Film Forming Foam (AFFF) Fire Extinguishers to give them the correct title will take care of any fire you are likely to get on board a boat.
As for gauges, they don't tell any lies. If the gauge is showing the correct pressure, you can be certain the extinguisher will discharge.
 

Talulah

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Part of the fire extinguisher servicing is to test the guages.
On the guage itself is a round clear dot of a sticker.
(Clear when new but coloured when replaced as part of the service. Colour denotes year.)
This round dot of a sticker is removed and then a pressure applied into the guage through this tiny hole to check it moves. This is just to check the needle isn't stuck. If the needle isn't stuck then you can rely on the guage.
 

prv

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This round dot of a sticker is removed and then a pressure applied into the guage through this tiny hole to check it moves. This is just to check the needle isn't stuck. If the needle isn't stuck then you can rely on the guage.

Mine move a little with temperature, so I'm happy they're working. Good point though that gauges apparently aren't totally infallible. Still much better than a "best before date" though.

I've bought a foam extinguisher to replace my big powder one this winter, after seeing the Crash Test blizzard video.

Pete
 
D

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Degradation of AFFF - Shelf Life - Not Just a Matter Of pressure

The link below is from Ansul, a manufacturer of various AFFF fire extinguishing agents. They state that in perfect conditions the concentrate has a shelf life of 25 years, but in premixed solutions it can be 3 to 5 years. What they are referring to is bulk AFFF available for fire fighting via some automatic system e.g. an oil rig or ships fire fighting system.

It is probably reasonable to assume that what is put into a typical fire extinguisher is mixed with water and at conditions which enhance the life of the AFFF.

The product is sensitive to temperature and is specified between 1 and 48 degrees celsius. Perhaps sailing in a hot country, or storage on board in freezing winters could shorten the shelf life and make the AFFF less likely to provide foaming and blanketing to specification. Its just something that we should be aware of.

AFFF is changed out yearly on desert based drilling rigs that have tanks of AFFF pre mixed to be drawn into the fire monitor. The rig mix water is very brackish and not likely to be of good quality.

The link below will automatically download the bulletin.

www.ansul.com/AnsulGetDoc.asp?FileID=8095
 
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maxi77

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When we replaced the old dry powder ones with foam we set of the old ones at sea just to see what happened, despite there being pressure using all three I might have put out a matchbox. Foam is cleaner more effective and I think reliable, even out of date.
 
D

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..... Foam ..... I think reliable, even out of date.

The bulletin from the link backs up your view and states that even when degraded, it is likely to still work, but that foaming and blanketing may be less than specification.
 

Stemar

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Not long after I got Jissel, I replaced one of the extinguishers that was about 12 years out of date. Out of curiosity, I tried it out and it still worked. I wouldn't have wanted to rely on it to put out anything I couldn't blow out, but I suspect that was because it was a tiny car type, rather than because of its age.

At home I have a CO2 extinguisher in the kitchen that I've had for close to 15 years and was second hand when I got it. I weigh it every year and it's still at its charged weight, so I assume it's going to do its stuff if I ever need it.
 

DavidGrieves

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Hi

Two main types of fire extinguisher...Stored Pressure, and Gas Cartridge.

Stored Pressure type, has an inlet valve to allow it to be pressurised, and needs a gauge to show you the pressure inside the cylinder. Don't open this type because it 'll dump the stored pressure.

Gas Cartridge is not stored under pressure so it does not need a pressure gauge (if it had a gauge it would show 0 ). It has a smaller cylinder inside which is pierced when the extinguisher is activated, this pressurizes the cylinder allowing the contents to discharged. This type of extinguisher can be opened and the contents checked, the small (CO2) cylinder will have a weight and date stamped on it. You can remove it and check its weight on a set of scales.

CO2 extinguishers do not need a gauge because it produce its own pressure. Good knockdown of the fire, will get into tight spaces, won't damage engines or electrics. But it has no cooling effect.

I do think an automatic system is the best. Whilst rafted up in Douglas a few years ago a boat had a fire in the engine compartment, owners not on board. I would have lost my boat without a boubt, if not for the auto extinuisher.
 

reeac

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Foam, or Aqueous Film Forming Foam (AFFF) Fire Extinguishers to give them the correct title will take care of any fire you are likely to get on board a boat.
As for gauges, they don't tell any lies. If the gauge is showing the correct pressure, you can be certain the extinguisher will discharge.

Not necessarily so! My house heating/hot water system is of the unvented design with a pressure vessel, pressure gauge etc. The gauge read approx. 2 bars for years but when a plumber dismantled things to replace a valve the gauge still read 2 bars -it was stuck. I have more confidence in its replacement as it shows small variations in its readings depending on whether the heating is on or off.
 

pappaecho

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Only problem with foam extinguishers is that they do not tolerate frost, which means they have to be taken off the yacht in winter and stored frost free. Perhaps the best balance is a mixture of foam and powder, with foam the best option but backed up with powder
 
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