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FIRE SAFETY => Portable Firefighting Equipment => Topic started by: Fire Monkey on January 20, 2017, 04:45:16 PM

Title: Replacing powder extinguishers
Post by: Fire Monkey on January 20, 2017, 04:45:16 PM
Hello,

When a powder unit comes to the end of its natural what is the best type of extinguisher to replace it with. The conditions are internal - boiler room - gas fuel.

Cheers,
Title: Re: Replacing powder extinguishers
Post by: AnthonyB on January 20, 2017, 07:40:04 PM
Unless it's being used for storage as well which would introduce a Class A risk we specify CO2.

The gas risk is excluded as most buildings do not have specialist staff trained & equipped in fighting live gas line or cylinder fires and the safest method of tackling the blaze (if at all) is by isolating the gas supply (& most general training reflects this) so as per the BS no need for a Class C extinguisher (once the supply is cut it's no longer a Class C fire, just whatever, if anything is still burning)

If there is a Class A risk then you either pair a water or foam with the CO2 unless you wish to use 'wet' extinguishers rated for direct electrical use like Water Mist or Britannia Aqua or Triclass extinguishers.
Title: Re: Replacing powder extinguishers
Post by: lancsfirepro on February 20, 2017, 04:15:54 PM
.........unless you wish to use 'wet' extinguishers rated for direct electrical use like Water Mist or Britannia Aqua or Triclass extinguishers.
Bear in mind this contradicts BS5306-8:2012 Clause 5.4.2  "Only non-conductive extinguishing media, such as carbon dioxide, powder or other clean agent, should be specified for use on electrical equipment."
Title: Re: Replacing powder extinguishers
Post by: AnthonyB on February 20, 2017, 07:52:20 PM
Yes because the UK flies in the face of the rest of Europe by not marking di-electric test compliant extinguishers suitable for direct use on electrical risks up to 1000V at 1m and doesn't install as such. With the extinguisher BS seemingly written by the trade for the trade this is no surprise, if an extinguisher is marked for electrical risks then electrical risks it can be used for if appropriate.

Why is the only inflexible bit of fire safety always related to the extinguisher industry?

Title: Re: Replacing powder extinguishers
Post by: colin todd on February 20, 2017, 11:02:37 PM
Tony, you are becoming paranoid. Inflexibility is alive and well throughout the fire safety profession, particularly overweight I/Os, who only ever exercise their tongues and cant touch their toes.
Title: Re: Replacing powder extinguishers
Post by: Mike Buckley on February 21, 2017, 12:46:42 AM
Just because you are paranoid, it doesn't mean they are not out to get you!
Title: Re: Replacing powder extinguishers
Post by: colin todd on February 21, 2017, 06:49:19 PM
I wouldnt be so paranoid if people would just stop following me around, stalking me and whispering about me.

OH no I have gone off piste again-sorry Big Al, it wont happen again.
Title: Re: Replacing powder extinguishers
Post by: lancsfirepro on March 08, 2017, 03:10:03 PM
Yes because the UK flies in the face of the rest of Europe by not marking di-electric test compliant extinguishers suitable for direct use on electrical risks up to 1000V at 1m and doesn't install as such. With the extinguisher BS seemingly written by the trade for the trade this is no surprise, if an extinguisher is marked for electrical risks then electrical risks it can be used for if appropriate.
Why is the only inflexible bit of fire safety always related to the extinguisher industry?
Because no one on the committee that puts together the BS wants to stick their neck out and say that it's safe to squirt water around electrics regardless of what test they have passed.
Title: Re: Replacing powder extinguishers
Post by: nearlythere on March 17, 2017, 09:23:12 AM
.........unless you wish to use 'wet' extinguishers rated for direct electrical use like Water Mist or Britannia Aqua or Triclass extinguishers.
Bear in mind this contradicts BS5306-8:2012 Clause 5.4.2  "Only non-conductive extinguishing media, such as carbon dioxide, powder or other clean agent, should be specified for use on electrical equipment."

The wording says "such as" Lancs. It isn't limiting it to those specifically mentioned.
Title: Re: Replacing powder extinguishers
Post by: lancsfirepro on March 17, 2017, 11:57:03 AM
I know what it says, and that's a bit of a stretch nearlythere; or it would surely include 'water-mist' etc after the 'such as' part.  The fact it then goes on to say what follows dismisses that idea:

NOTE Some water-based models with a spray type discharge have passed the discharge conductivity test in BS EN 3. This does not necessarily mean that these types can be used directly on fires involving electrical equipment. However, if the discharge of one of this type, being operated in the fashion prescribed by the manufacturer, inadvertently splashes onto electrical equipment, then the spray type discharge will afford the user more protection from electrical shock than the discharge from a jet type extinguisher or a spray type which has not passed the
BS EN 3 conductivity test.


Basically, 'safe around' not 'safe on'.  This is what is being taught on the FIA extinguisher courses to BS5306-3 & 8.
Title: Re: Replacing powder extinguishers
Post by: nearlythere on April 27, 2017, 03:16:01 PM
I just read where a BAFE accredited fire extinguisher engineer has stated that powder is the only recommended extinguisher for use on gas appliances. Is this the view of BAFE? I though the best extinguisher for a gas appliance was the yellow lever. 
Title: Re: Replacing powder extinguishers
Post by: SeaBass on April 27, 2017, 04:03:40 PM
I think I've met that chap. Is he the one who said that it was compulsory to replace the metal pin and the plastic pull clip on fire extinguishers at each annual service because they wear out?
Title: Re: Replacing powder extinguishers
Post by: nearlythere on April 27, 2017, 06:11:35 PM
I think I've met that chap. Is he the one who said that it was compulsory to replace the metal pin and the plastic pull clip on fire extinguishers at each annual service because they wear out?

 :D Probably. And that a Co2 should not be in a kitchen in case the horn breaks off. Powder best.
Title: Re: Replacing powder extinguishers
Post by: AnthonyB on April 27, 2017, 09:54:44 PM
I just read where a BAFE accredited fire extinguisher engineer has stated that powder is the only recommended extinguisher for use on gas appliances. Is this the view of BAFE? I though the best extinguisher for a gas appliance was the yellow lever. 

You are correct, and BS5306 supports this. Most fire safety and fire extinguisher training doesn't teach anything other than cutting off the supply for Class C fires as otherwise there is an explosion risk. If you are able to cut off the supply you no longer have a Class C fire, ant residual fire will be another class (often Class A) and extinguisher provision should suit the residual risk, not Class C.

The provision and existence of Class C extinguishers is aimed at specialist risks where in order to isolate the supply you need to extinguish the flame first - but in this instance staff are (or should be) given advanced training and in some situations it's part of a fire team approach where the staff have PPE and are also using hose lines for shielding and cooling - far beyond Joe Average in a typical commercial premises who has done his interactive online fire safety course...........