Fire extinguisher advice

[Moriarty]

Stumbled across a flee market yesterday and came away with a rather nice old copper extinguisher which I think could have a lot of jet pack potential. Its of a design I have not seen before but appears to be manufactured by  National - ? the second word being illegible and is stamped 1953.

However it is still charged and the label states an operational presser of 350 lbs and warns "never refill with water" and the need for maximum ventilation after use. This makes me wonder were the manufacturers mealy angling for people to get the extinguisher recharged with their preparatory mix or are the contents in some way dangerous when mixed with water?

I don't know if I should mealy step out side and let it go or excises a little more caution. I also need to clean the inside thoroughly as I would like to solder pipe work etc to it and the water warning has me raising an eye brough.

Anyone have any experience or advice to offer on this one?

It only cost me £3 

[akumabito]

Well, having an ingredient which acts violetly with water wouldn't be a very wise idea for use in a fire extinguisher. After all, most fires are fought with large amounts of the stuff..

Does it say what it's filled with? And does it look to be refillable?

I think you could just empty the thing, then depressurize it. After that, it might take a little bit of pursuasion to unscrew the top.. I don't see any reason why you couldn't openher up to give it a good clean..

Got any pictures of it?

[von Corax]

Photos would be helpful, as would a complete transcription of the instruction/warning label.

In the mean time, I would suspect you have either a dry-chemical or foam extinguisher — the latter is used on liquid-fuelled fires, while the former is also safe to use on electrical fires. (Neither water nor foam — being water-based — can safely be used on electrical fires, and water will cause petroleum fires to spread.) The act of refilling with water would be relatively safe, but using it after it had been unexpectedly refilled with water could prove quite deadly. As to the "maximum ventilation" warning, it's merely that both dry fire suppressant and foaming agents can evolve noxious fumes when in contact with flames, and you should probably provide maximum ventilation after extingushing any fire, regardless of what you used.

To answer the meat of your question, I second Aku's opinion that you could probably safely depressurize it, then unscrew the valve assembly and give it a good flush and rinse with hot soapy water.

[Captain Shipton Bellinger]

The fact that it appears to be pressurised rather than plain hand-pumped militates against this extinguisher containing carbon tetrachloride but, just in case, check very thoroughly to see if there is any mention of CTC on the extinguisher.

CTC was widely used smaller hand-held extinguishers until the late 1950s. Warnings about maximum ventilation are best heeded—it's evil stuff. If you even suspect that CTC is involved don't discharge the extinguisher, don't empty it down the drain, especially don't burn it off, don't get it on your skin or in your eyes.

Your local council should be able to give you advice on disposing of hazardous waste, but make sure you talk to the right people (I was once told the best way to dispose of a quantity of picric acid was to "bung it in the skip").

[Moriarty]

Thanks for the replies, I will get a picture of it for your perusal. the transfer is very damaged and hard to read though.

I had heard that some old extinguisher charges are water with an additive which is now regarded as carcinogenic. My Pyrene model states "carbon tetrachloride"  and "must not be washed out" but Corax your point regarding electrical fires and water is well made and makes good sense.

I am sure I can make out the word vehicle, possibly originally public transpot vehicles.

I have never uploaded images before so please bear with me.

[Moriarty]

Now this is exactly why I am asking. I am now, having look again at the label pretty sure I can make out the remains of a capital T.C.- originally CT?

Thank you for the heads up  Captain, so it looks like lots of soldering to the canister could be pretty illadvised unless thoroughly cleaned?

[Captain Shipton Bellinger]

I am sure I can make out the word vehicle, possibly originally public transpot vehicles.

Hmmm… During the 1940s & '50s the most common type of extinguisher found on public transport used CTC as the suppressant.

Now this is exactly why I am asking. I am now, having look again at the label pretty sure I can make out the remains of a capital T.C.- originally CT?

Thank you for the heads up  Captain, so it looks like lots of soldering to the canister could be pretty illadvised unless thoroughly cleaned?

Well, it's your call, but personally I wouldn't apply heat until it had been well washed out with soapy water.

[Moriarty]

Hmmm... indeed , I have just read that when heated the contents can turn to  Phosgene gas !!! and I have passed up on loads of these at flea markets etc, due to them being too dented and they were nearly all full! Gulp!

As an aside I note a few moderator icons at the bottom right of my posts, have i been in breach of forum etiquette? if so I do apologise and what am i doing wrong?

[akumabito]

Those icons appear standard beneath every post, so no worries there..

I had no idea such evil stuff was used in old fire extinguishers.. but then I shouldn't be surprised as they came from an era where asbestos was heralded as the greatest construction material ever..

[ktara]

Do you have a fire extinguisher service company in your town?  They might be able to discharge it safely and then open it for you.  Or at least advise you on what's safest to do.  It would be worth paying them for the service so you can use it safely

[Siliconous Skumins]

Chances are it uses either a bromide or bromochloride suppressant, neither of which are a good idea to inhale in volume...

Strictly speaking, it requires disposal at a toxic waste dump, but it is possible to "dispose" of it yourself (read: discharge it in a field somewhere, and make sure your UP WIND!). If there is any pressure still remaining in the gas cylinder (doubtfull) it could be dangerous to try to disassemble the extinguisher. So set it off first, and if nothing happens leave it for an hour or so just to be sure. Then, and only then should you attempt disassembly - but CAREFULLY! Remove the pressure vessel, and pour out the liquid into a suitable container with a tight fitting stopper or cap - then take it for disposal at the nearest chemical waste dump (try the council tip, just tell them you don't know what it is...).  Dispose of the compressed gas canister safely - it may or may not be empty, and at that age is probably unstable (and could be very NASTY if it explodes). Take it to the council waste dump, tell them it's from an old air gun.


I take no responsibility for any of your actions which may result in harm, injury, death or environmental damage... 

SS

[Moriarty]

thanks for all the advice everyone, its abandoned in the back yard at the moment.

If my wife reads this im in big trouble and the project will die before its started.

[Mr Peter Harrow, Esq]

At least it won't be after the project is started if you follow the above advice.

[Moriarty]

Right so now I just have to wait for a dry day with a strong off shore breeze (the stronger the better) and I am in business, naturally the weather has turned damp and still damn it. In the mean time I will busy myself sorting out a peg spanner thing to remove the plunger section, I am sure something similar is used for adjusting shock absorbers. That and scour around for rocket nozzles.