Fire extinguishers

[Graham_Wright]

I currently have some pretty green ones (Shush!) but am inclined towards CO2. I can install a CO2 bottle alongside the engine to douse any fire therein and I could have two more in the accommodation.

I understand powder is very effective but leaves an impossible mess (if that really matters).

Any views please?

Is it possible to refill CO2 bottles?

 

[[70521]]

This link might help in the choice of fire extinguisher

http://www.nwfiresolutions.co.uk/article/14/guide-to-uk-fire-classes-from-a-to-f

CO2 is basically for an electrical fire.

I strongly advise you to consider water mist.

 

[Graham_Wright]

Good link steer - thanks.

The engine space is substantially sealed save for the combustion air intake. I have a deep cockpit locker alongside, which could house the cO2 bottle to be activated from the cockpit. The air intake could be choked from the cockpit also.

I recall a RNLI advisor declaring that water (i.e. water not mist) should not be used in an electrical environment as "they don't mix". I don't think that is valid for 12v!

I like the idea of the water mist as it does not leave a mess like powder or foam.

 

[bedouin]

Every time this is brought up the opinion seems to be that water mist are the best all round fire extinguishers. The only minor downside is that their official ratings don't reflect their capability so it is hard to satisfy the RYA's recommended capacity using Water Mist (either A or B, can't remember which).

 

[[70521]]

Every time this is brought up the opinion seems to be that water mist are the best all round fire extinguishers. The only minor downside is that their official ratings don't reflect their capability so it is hard to satisfy the RYA's recommended capacity using Water Mist (either A or B, can't remember which).

Sounds like the RYA need to update their recommendations.

 

[bedouin]

Sounds like the RYA need to update their recommendations.

Or the people who design the ratings test should update theirs - there is something in the specification of the rating tests that means small water mist extinguishers don't even qualify for A or B ratings even though they are more effective than other types of equivalent size.

 

[[70521]]

Or the people who design the ratings test should update theirs - there is something in the specification of the rating tests that means small water mist extinguishers don't even qualify for A or B ratings even though they are more effective than other types of equivalent size.

I suspect the wheels of conformance turn slowly, They certainly do in my industry.

 

[bedouin]

I suspect the wheels of conformance turn slowly, They certainly do in my industry.

I actually carry a couple of cheap fire extinguishers that I would never use just so I can tell the insurance company that I have the recommended 13A/89B

 

[vyv_cox]

I bought two of these after watching their videos. They look very impressive in action. Firepal are very guarded about exactly what the extinguishant is, 'nano-technology' is all we get unless someone knows a better source. https://www.firepal.co.uk/

 

[Chris_Robb]

This article list a number of Halon replacements
https://www.h3rcleanagents.com/products.htm#bpr

They can be bought either a automatic extinguishers or hand held.

Given these alternatives, I would avoid CO2 as it really is only used in engine room fires where the area is sealed. Remember CO2 is deadly to your ability to Breath. 40,000ppm (4%) is fatal over a period of time, and 7 to 10% is almost immediately lethal.

Use of the extinguishant in a confined space (a boat) is in my view not a good idea, especially when there are other easier systems around.

The bottles are also very heavy and bulky to have sufficient capacity to put out an unsealed engine room fire.

 

[benchmark]

Even though I still have a couple of Co2 extinguishers on my boat, I have moved over to the new generation of fire extinguishers that don’t require servicing, can be used for all types of fires, do not make a mess , do not expire, lighter to carry, discharge for more seconds .

 

[superheat6k]

My view of a fire extinguisher is that it should knock down and destroy the fire within a few seconds, and prevent re-ignition. The best thing for this is a pyrolysing agent, which is what the Halon and its replacements do. In pyrolysing the gas burns briefly and envelopes around the entire flame knocking out by depriving the oxygen. AFFF has a similar effect as a liquid largely a water solution.

AFFF was when I served the common general use fire extinguishing agent used by the Royal Navy, and we were told we could use it on electrical fires. Halon and BCF were used in the engine rooms and having seen it knock out a fire on an Olympus Gas Turbine in an instant I would not out of choice place anything else (albeit HFC 227A now) in my engine room.

DO NOT breathe in the vapour after it has pyrolysed - hydrofluoric acid is very nasty. Yes it does leave a mess behind but better that than a hull burnt level to the water line.

CO2 drench can work, but does not pyrolyse the flame, so a draught from another engine running for instance can allow the fire to re-start. Halons work at a very low % concentration.

Dry powder is messy and only effective if you can direct it right at the base of the fire. Personally I feel a bucket of water is likely to be more effective than dry powder, and there is no shortage of that in our leisure environment.