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Advances in fire extinguishers

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Registered: 21-03-2011

Advances in fire extinguishers

I've just had to buy a fire extinguisher for our holiday home. I'd not realised there's been developments in the technology. I ended up choosing a dry water mist extinguisher" It is good for:
Class A - Wood, paper, textiles
Class B - Flammable liquids
Class C - Gaseous fires
Class F - Cooking oils and deep fat fires
Also live electrical fires.
We also have a fire blanket for the kitchen.
Is there anything missing?
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nanotm
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Re: Advances in fire extinguishers

how can anything water based be safe on electrical or oil fires ?
I ask because oil floats and water is conductive, those two facts don't change regardless of how you package it
personally I would rather use something like foam or powder since they both "smother" any fire (when used properly) and remove one of the 3 necessary things from the "fire triangle" ........
just because your paranoid doesn't mean they aren't out to get you
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Re: Advances in fire extinguishers

Apparently, pure water does not conduct electricity especially in ultra-fine mist. I had might concerns too so I checked.
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nanotm
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Re: Advances in fire extinguishers

it would depend on the tension of the electrical supply,
if pure water was non conductive why would you add it to lead acid battery in order for electron flow to occur ?
just because your paranoid doesn't mean they aren't out to get you
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Re: Advances in fire extinguishers

http://www.nationwidefireextinguishers.co.uk/c75500/dry-water-mist-fire-extinguishers.html
Quote
The new dry water mist fire extinguishers cover a broader range of fire ratings than the standard water fire extinguishers.  The new ground-breaking technology means that the water mist fire extinguishers can be used on deep fat fryer fires and they have passed the 35kV dielectrical test.  This ensures that the water mist fire extinguishers can be safely used near electrical equipment.

Regarding the lead acid battery the clue is in the name - it contains sulphuric acid which is the primary conductor http://chemistry.about.com/od/chemicalcomposition/f/What-Is-Battery-Acid.htm
Quote
Answer: Car or automotive battery acid is 30-50% sulfuric acid (H2SO4) in water. Usually the acid has a mole fraction of 29%-32% sulfuric acid, density of 1.25–1.28 kg/L and concentration of 4.2–5 mol/L. Battery acid has a pH of approximately 0.8.
nanotm
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Re: Advances in fire extinguishers

given that its about what the water touches and combines with I'm not questioning there lab test results inside the clean room but what it will do in the real world.
in a lab test quick clot was proven to seal arterial holes in seconds however in field conditions it did nothing more than cause agony and create a plug to prevent the arterial bleed from freely flowing out of the body,( the people with the holes in still bleed to death) 
as I said you put pure H2O into battery cells in order for electrons to flow
just because your paranoid doesn't mean they aren't out to get you
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Re: Advances in fire extinguishers

No you don't
You top up with distilled water to avoid contamination of the acid solution
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Re: Advances in fire extinguishers

Pure water has a resistivity of between 1MR and 10MR per cm depending on the purity.
If you are putting out an electrical fire from 30cm then you would have around 30MR @ 230v = 0.000008 amps (0.008mA) of current flowing if you were were a perfect ground. You probably wouldn't even feel a tingle.
TORPC
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Re: Advances in fire extinguishers

make sure the iced freezer particle(s) do not touch metal & Viola you have distilled water Wink
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Re: Advances in fire extinguishers

Quote from: nanotm
given that its about what the water touches and combines with I'm not questioning there lab test results inside the clean room but what it will do in the real world.

Check the video on this page, not exactly 'clean room', looks more like 'real world' to me.  Wink  http://www.safelincs.co.uk/e-series-water-mist-fire-extinguishers/  Skip to about 2:35 for 'electrical test'.
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PowerLee
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Re: Advances in fire extinguishers

As someone that deals with industrial traction lead acid batteries at work I'd only try to use deionised water to top a battery up.
Deionised water is the preferred liquid of the battery manufacturers we deal with.
Distilled water would be ok to use for smaller automotive car batteries as these don't have the same strict warranty conditions & cost of replacement that an industrial traction battery does.
Deionised water is also far cheaper & quicker to produce then distilled water.