dry powder discharge

[forrest fire]

hi i need to get the power out of a extinguisher its a pressurized fire extinguisher i wanna get the gas out without making a load of mess and reuse the powder, so who got good tips or tools to do this 

[Safelincs]

Cut off one leg from a dense pair of jeans, sew one end of the leg closed and fix the other end round the hose with a rubber band. Now tip the extinguisher upside down. The only powder that will be expelled when you trigger the extinguisher will be the powder in the dip tube. If you are trying to re-pressurise the extinguisher, please be aware that it is difficult to make the extinguisher air tight again, as the powder residue on the valve can lead to leaks. Wear a face mask while you are doing this, just in case powder gets into the air.

Harry

 

 

[AnthonyB]

Yes, as above. Back in the day when powder extinguishers were routinely refilled and discharge tested they made powder blow out bags for this purpose, but a home made one and inverted discharge will do what you need.

What are you reusing the powder for? If it's recharging a different extinguisher you need to be sure you aren't going to mix incompatible powders (e.g. BC powder in an ABC powder extinguisher or vice versa) or use and inferior grade that invalidates the fire rating (e.g. 40% MAP powder in an extinguisher manufactured with 70% MAP powder). Any powder extinguisher being recharged needs a full strip down in order to clean out the valve and spindle to ensure it seats fully or it will just slowly leak off after re-gassing.

[forrest fire]

dont you have to look inside the tank after 5 years to make sure its all nice inside i know about the water ones can be turned upside down but was not sure about powder

[Safelincs]

Yes you do if you service an extinguisher in accordance with British Standards. For this you require a powder suction machine with refill capability. Not something I would recommend until you had some training.

[AnthonyB]

You are meant to internally examine every 5 years with a stored pressure after the discharge test as part of an Extended Service, but hardly anyone bothers as it's not cost effective.

Cartridge powders are opened up annually, but you don't have to remove the powder each year, just agitate and check the condition.

[forrest fire]

Yeah so discharge test turn out side down and pull the lever collect the power in a bag kinda thing open up look inside. I have the training but we didn't cover power that in depth as much as water 

[forrest fire]

I could just make a box with a good filter on at the lid and hose going in and blow it all into that 

[AnthonyB]

If you are discharge testing you will need to use new powder unless you have a proper closed circuit recovery system such as the Getz Superkan or Vacufill as the powder will get contaminated and absorb moisture.

Virtually no one in the trade refills powder now as it's just not cost effective anymore

[forrest fire]

so yeah i understand so after 5 years just replace the hole thing because it works out cheaper what do with these old fire extinguishers after the 5 years and get new ones 

 

[green-foam]

Although what you say is true, you should replace the whole extinguisher, what type of premises are these / this extinguisher in?

Also, what size is it / they? (in Kg)

[AnthonyB]

On 04/08/2016 at 7:17 PM, forrest fire said:

so yeah i understand so after 5 years just replace the hole thing because it works out cheaper what do with these old fire extinguishers after the 5 years and get new ones 

 

Your fire extinguisher maintenance company can environmentally dispose of old fire extinguishers and issue a waste transfer note for your records - you can't just bin them (as someone found out when they blew up a bin lorry this way)

[Guest derone]

when you emty a fire extinguisher under pressure does it remove any of the silicon coating of the powder .Would it be o/k to use again.

If so would it be as good as new ?

[Shawn Bosworth]

On 01/08/2016 at 22:49, AnthonyB said:

If you are discharge testing you will need to use new powder unless you have a proper closed circuit recovery system such as the Getz Superkan or Vacufill as the powder will get contaminated and absorb moisture.

Virtually no one in the trade refills powder now as it's just not cost effective anymore

 

5 hours ago, Guest derone said:

when you emty a fire extinguisher under pressure does it remove any of the silicon coating of the powder .Would it be o/k to use again.

If so would it be as good as new ?

 

As previously mentioned you could reuse the powder if it had been discharged within a closed system to ensure no moisture or contamination has occured. Otherwise the answer is no, it is not OK to use again.