Water mist fire extinguisher

[DoubleEnder]

I’m doing some displacement work in the cabin, as launching doesn’t look very likely, paint and varnish sort of thing and tidying up, emptying lockers 100% instead of the 90% I do every year. Etc etc. Fire extinguisher mounting brackets are off and I am thinking of changing from current foam extinguishers to water mist type. I have an alcohol cooking stove, a flued charcoal heating stove which is rarely used, and a diesel inboard. No petrol on board, usual bits and bobs of paint, spare engine oil etc all usually stored in the bilge.
The current extinguishers are not yet date expired and I won’t change until it looks more likely we can get the boat in the water, but would appreciate any views.

 

[JimC]

Water mist extinguishers are very vulnerable to frost I believe. Something to consider if you leave them on the boat over Winter. I use my boat all year (only as a caravan in Winter) and this put me off going to water mist.

 

[sarabande]

I have changed to water mist at home, in the caravan, and on the boat. I am convinced by the Safe Lincs Fire videos..

The great advantages are one type of extinguisher for all fires on board, no learning 2 or 3 different techniques, and also no chemical residues to affect engine intake, electrical connections, or breathing.

 

[boomerangben]

I am no expert on this but believe this sort of system is built into many commercial vessels. It seems to work by being very effective at taking heat out of the fire and presumably that is how it takes out one side of the fire triangle or pyramid or tetrahedron whatever it is these days. The key is achieving a small enough droplet size so the nozzle must be kept in tip top condition. My only concern would be possible corrosion of the nozzle in the leisure boat scenario?

 

[[70521]]

Water mist extinguishers are very vulnerable to frost I believe. Something to consider if you leave them on the boat over Winter. I use my boat all year (only as a caravan in Winter) and this put me off going to water mist.

If i was well above sea level I'd be worried.

If I was to store the extinguisher outside I'd be worried.

 

[Graham_Wright]

What trick did you use to legally access your boat in the present situation? Is it in the garden?

 

[JohnGC]

Water mist extinguishers are very vulnerable to frost I believe. Something to consider if you leave them on the boat over Winter. I use my boat all year (only as a caravan in Winter) and this put me off going to water mist.

A couple of years ago I forgot to remove the cockpit locker DWM extinguisher during the winter layup. It needed replacing the following year. This was on the hard in Plymouth. Those inside the cabin are fine, although I should point out we have and Etap (double hull with foam filling, so well insulated).

 

[geem]

I am no expert on this but believe this sort of system is built into many commercial vessels. It seems to work by being very effective at taking heat out of the fire and presumably that is how it takes out one side of the fire triangle or pyramid or tetrahedron whatever it is these days. The key is achieving a small enough droplet size so the nozzle must be kept in tip top condition. My only concern would be possible corrosion of the nozzle in the leisure boat scenario?

The nozzles are normally s/s in the applications I have been involved with in the past. In fact the whole installation was s/s. I have only been involved with high pressure water mist in data centres. These systems operate at 200bar. Water mist is particularly good in engine room fires as it will suppress a fire with minimal damage to an engine. Even the water mist entering a running diesel air intake will do no damage as long as it is a high pressure system with super fine droplets. We had data halls protected above and below raised floors and generator rooms. It was originally invented for ships engine rooms. It is far more effective than low pressure sprinkler systems and uses a tiny amount of water by comparison. I guess a good solution for the engine space on a boat would be a self contained automatic extinguisher. I am not sure how effective they would be as a handheld unit on a boat

 

[Pete7]

Having spent several enjoyable weeks practising putting out fires in the Army, I learnt just how effective AFFF extinguishers are. We now carry:

1 x 3L AFFF
1 x 1L AFFF
1 x 2kg CO2
1 x 1.5kg clean gas auto in engine space
1 x fire blanket
1x bucket

The water mist look interesting and could supplement other types. Check how long they will work for. Small extinguishers are often just a few seconds and then think how long it might take to put out the frying pan full of sausages and black pudding if it caught.

Cheaper to buy on line rather than the chandlers.

Pete

 

[JimC]

Having spent several enjoyable weeks practising putting out fires in the Army, I learnt just how effective AFFF extinguishers are.....

The Safelincs videos show the water mist extinguishers out-performing various other types of extinguisher, but don't include AFFF foam in the comparisons. Not sure if anything can be read into this. AFFF foam extinguishers certainly are higher rated size for size

 

[NotBirdseye]

AFFF tends to be expensive and you have the residue left over.

 

[[70521]]

The Safelincs videos show the water mist extinguishers out-performing various other types of extinguisher, but don't include AFFF foam in the comparisons. Not sure if anything can be read into this. AFFF foam extinguishers certainly are higher rated size for size

Fomtec AFFF 1% A is intended for use on class B hydrocarbon fuel fires such as oil, diesel and aviation fuels. It can be used with both aspirating and non-aspirating discharge devices. Fomtec AFFF 1% A is especially suited whenever rapid fire knock-down is essential.

Only rated for Class A & B fires so about as useful as a chocolate teapot for a gas cooker (Class C) or electrical fires.

 

[rogerthebodger]

Is there any instructions anywhere showing how to construct a Water mist fire extinguisher ?

 

[JimC]

Faced with the need to re-equip my own boat I've been googling high and low for a comparative test of water mist and AFFF foam extinguishers. I finally found one here

The results may surprise you.

 

[NotBirdseye]

AFFF is not rated yet for C,D or F class fires. Water Mist is rated for all except D so....

But I'd like to see a video demonstration tbf.

That said it seems like buying AFFF and CO2 is cheaper than buying water mist... depends on whether you like that residue...

 

[[70521]]

Faced with the need to re-equip my own boat I've been googling high and low for a comparative test of water mist and AFFF foam extinguishers. I finally found one here

The results may surprise you.

Hands up who sails with a deep fat fryer making chips/frys while underway?

The paper is too specific and does not address fires on boats.

 

[grandpaboat]

The first time I encountered these water mist extinguishers was on an STWC / MCA firefighting refresher course. I was most impressed and will certainly be replacing mine with them the next time I renew.

 

[UK-WOOZY]

i put one in my boat about 2 years ago next to the galley steps, its this one-

1ltr Water Mist Fire Extinguisher - UltraFire for sale online | eBay

(excuse the pic, it just about shows the extinguisher location. (i was fixing a metal plate above the stove with sail battens)

 

[Pete7]

Fomtec AFFF 1% A is intended for use on class B hydrocarbon fuel fires such as oil, diesel and aviation fuels. It can be used with both aspirating and non-aspirating discharge devices. Fomtec AFFF 1% A is especially suited whenever rapid fire knock-down is essential.

Only rated for Class A & B fires so about as useful as a chocolate teapot for a gas cooker (Class C) or electrical fires.

What fire fighting equipment do you carry on your yacht?

 

[[70521]]

What fire fighting equipment do you carry on your yacht?

Four water mist extinguishers (one in each sleeping cabin, one in the saloon and one for the engine compartment), a fire blanket and several buckets just in case we have to use sea water (oh I could also use a bilge pump).

The poorly made point that I was trying to make was the paper referenced was for AFFF for use on a Class B flammable liquid fire. In the papers case vegetable oil; hence the comment about chip pans. When I look at the materials on the boat I see a lot of Class A stuff, wood paper. The greatest risk of fire is the gas stove (Class C flammable gasses) and an electrical short (Electrical fire).

Having spent three lovely days with the Devon and Somerset Fire and Rescue Service over the last nine years being trained in the use of fire extinguishers - got to wear the hunky uniform, boots and helmet - I've seen them close up. There is no way I want to fight a fire in the boat using dry powder in seconds you can't see or breath and I hate to thinking what it might do to an engine if ingested. CO2 is brilliant for electrical fires but then you need to get rid of it from a confined space as it is heavier than air. Foam is much like dry powder I'll let you do the cleaning after the fire.

What fire fighting equipment do you carry on your yacht and what is the reasoning behind carrying it?