Fire extinguishers in 2020

[Jammer]

I am getting my trailer sailor ready for spring and have fire extinguishers on the brain. A question I am pondering is whether to obtain the typical inexpensive chandlery fire extinguishers, or upgrade to something that is more effective, less messy, or both.


One possible course of action I am considering is obtaining two inexpensive fire extinguishers, plus a fire blanket.


Background information and what has changed since the last thread

• A USCG approved AFFF (foam) extinguisher is now available, the Amerex B250CG. It is B-II rated, costs $315 including the bracket, 7" diameter, 25" high, about 25 pounds. They must be protected from freezing. This agent is broadly effective on all types of fires likely to occur on a boat.
• Despite the long-standing ban on new production, Halon 1211 remains legal for purchase and use in the USA as industrial and military stocks are recycled and repackaged. It cannot be imported into any nation under the Montreal Protocol, and cruisers crossing international borders have reported serious problems including confiscation and disposal charges.
• Not mentioned in other threads are the extremely toxic decomposition products that can be produced when Halon 1211, Halotron, or any other chlorinated hydrocarbon extinguishing agent can produce if used in a fire. Phosgene gas is the most serious of these. It has few warning properties and even brief exposures can lead to death or chronic health problems.

Regarding different types of dry chemical extinguishers

There are three chemical agents in widespread use.

• Monoammonium phosphate (MAP), usually sold as "ABC dry chemical." Widely used because it is effective on all types of fires, the problem with it is that it produces an acrid cloud of yellow dust when used in confined areas and makes a huge mess. Cleanup is complicated by the fact that it forms molten blobs when heated and by the fact that it is corrosive when damp or wet.
• Sodium bicarbonate, usually sold as "standard" dry chemical. It is half as effective as MAP on gas and oil, and not at all effective on ordinary combustibles.
• Potassium bicarbonate, "Purple K." Widely considered the most effective extinguishing agent on gas an oil. Not effective on ordinary combustibles. Cleanup is bad but not as bad as MAP.

Chandlery fire extinguishers are usually either MAP or sodium bicarbonate. Purple K is available from places that sell fire extinguishers. It went through a brief surge of popularity for recreational marine use in the 1970s and has sort of fallen into obscurity since. It is still in widespread use by the navy, oil refineries, airports, and other high-hazard locations.

[xxxxx]

Go with a CO2 extinguisher, not a dry chem.

First, no mess, and it's effective on ABC fires.

Second, it's heavier than air. As a last resort it can be used to flood the cabin from the "relative" safety of the companionway, which can smother the fire.

That's how large ships deal with engine room fires, incidentally. They flood it with CO2, which displaces the oxygen.

[rslifkin]

On a boat, I'd rather have AFFF than Purple K. In a car, however, I'd tend the other direction, as Purple K doesn't freeze.

[tkeithlu]

I second the post of our XXXXX friend. While ABC powder is cheap and meets the CG requirements, it will destroy any electronics it touches, either by grit or by corrosion. It is horrible to clean up, and minimally effective on Class A fires. My university spent $250,000 restoring portraits after two students got in a dry chem extinguisher fight in an art gallery.

But, to go beyond meeting the requirements over to actually protecting space: CO2 bottles from your local welding supply are cheap. Running a 20# bottle through some 1/2' copper tubing into your engine space or even your living quarters is simple enough. Close the hatch, open the valve from the comfort of a safe place, and totally fill the space with CO2. No mess, no clean up. Vastly cheaper than flooding the same space with Halon or its relatives.

One step back is a fire port into your engine or fuel tank or whatever, sized to fit your CO2 nozzle. Again, you close off the space, you don't enter the space, you flood the space.

Realize when you are thinking about this that fiberglass resin burns like greased paper and produces very toxic gas. Breathing that stuff will both plastic coat your lungs and poison you. If a fire actually does get started in your boat, you want to be able to respond from standing on the upwind rail ready to jump. I leave with this charming stock photograph:

[SVHarmonie]

Originally Posted by xxxxx

Go with a CO2 extinguisher, not a dry chem.

First, no mess, and it's effective on ABC fires.

Second, it's heavier than air. As a last resort it can be used to flood the cabin from the "relative" safety of the companionway, which can smother the fire.

That's how large ships deal with engine room fires, incidentally. They flood it with CO2, which displaces the oxygen.

BAD BAD BAD ADVICE.

Just because it is used on large ship engine room fires does NOT make it best for small boats, for lots, and lots of reasons.

You realize that a ships engine room MUST be evacuated and all personnel accounted for before such a system is set off? Becasue anyone left behind is DEAD. Fire or no fire.

Any concentration of CO2 sufficient to put out a fire will also extinguish YOU--within seconds. Don't take my word for it:
https://www.nist.gov/system/files/do...h/R0000286.pdf

The idea that you can "flood a cabin from the cockpit" with enough CO2 to put out a fire is also just plain WRONG. The minimum concentration of CO2 needed to put out a fire is 34% by volume. Let's run some numbers...

The interior volume of a 32 foot boat is roughly: 32 * (9 *0.67) * 6 = 1150 cu feet, or 1150/380 = 3 pound-moles of air

So we need 3 * 34% * 44 = 45 POUNDS of CO2 as a MINIMUM to "flood" the cabin sufficiently to extinguish a fire. And that assumes there is no dilution from hatches or other ventilation. Do you carry a 50 lb CO2 extinguisher? Probably not... Oh, and if you COULD put out a fire this way, the cabin would be immediately deadly to enter until it was sufficiently ventilated--which you would know... how?

CO2 is a great system for suffocating a fire in a tightly confined engine room and can be used that way safely and effectively. Even a relatively small engine room takes a 20 pound tank of CO2. It is not at all suitable for habitable areas of a small boat.

A fire on a small boat is a disaster, even if it is quickly put out. I have seen 4 boat fires, and put out 2 of them. I very much hope to never see another.

By far the most common fire in the cabin of a boat is in the galley. Every boat should have a fire blanket within easy reach of the cook. No muss, no fuss.

[NYSail]

The CO2 sounds interesting but to be honest if my boat is on Fire I dont care about a mess..... as long as I can put it out. I have regular fire extinguishers all over the boat plus two fire blankets.

Small price to pay...... in my opinion at least!

[Jammer]

I have CO2 fire extinguishers in the kitchen and garage of my house. I used one "in anger" once on a welding-related fire and I practice with them every 5 years or so when they are due for hydro test.


I believe they are the best of the clean-agent choices but agree that they are not a panacea. You have to get close to the fire with them -- really close, within a few feet ideally. They're big and heavy for what they do.


I think that the new foam extinguisher is probably the best answer for boats that can devote enough space for one and that aren't subject to freezing temperatures.

[xxxxx]

OK. Here we go.

Originally Posted by SVHarmonie

BAD BAD BAD ADVICE.

Disagree.

But what do I know? I've only been in the Fire Service 12 years.

You realize that a ships engine room MUST be evacuated and all personnel accounted for before such a system is set off?

Yes.
I've been fortunate to tour and pre-plan cargo ships for the sole purposes of pre-planning and confined space rescue.

Any concentration of CO2 sufficient to put out a fire will also extinguish YOU--within seconds.

Agreed. So too will a fire that continues to burn.

You seem to be conveniently ignoring I said as a last resort--before abandoning your vessel.

The idea that you can "flood a cabin from the cockpit" with enough CO2 to put out a fire is also just plain WRONG

Actually, it isn't wrong. In fact, you go on to prove that it can work:

The minimum concentration of CO2 needed to put out a fire is 34% by volume. Let's run some numbers...

The interior volume of a 32 foot boat is roughly: 32 * (9 *0.67) * 6 = 1150 cu feet, or 1150/380 = 3 pound-moles of air


So we need 3 * 34% * 44 = 45 POUNDS of CO2 as a MINIMUM to "flood" the cabin sufficiently to extinguish a fire.

First, he has a trailer sailer. I don't know of many 32ft trailer sailers.

Second, you don't need to flood the entire volume of the boat. As tkeithlu suggested, you might just flood the engine compartment.

Third, that's only two about 20lb extinguishers.

Again, we're talking as a last resort. This is the last attempt before jumping overboard.

And that assumes there is no dilution from hatches or other ventilation.

Correct. It's also assuming no oxygen has been used in the combustion.

Oh, and if you COULD put out a fire this way, the cabin would be immediately deadly to enter until it was sufficiently ventilated--which you would know... how?

It's not an IF. You CAN put out a fire this way. You just showed us it's possible and it would be worth attempting before jumping overboard.

Of course it would be deadly to enter the cabin space, but not just because of the CO2. The cabin would be full of the products of combustion: VOCs, Hydrogen Cyanide, Carbon Monoxide, etc.

It'd be deadly either way. That's a different discussion. The difference is that there might be a boat left at the end of it.

Every boat should have a fire blanket within easy reach of the cook. No muss, no fuss.

No disagreement. He asked about extinguishers.

You seem hellbent on focusing strictly on trying to flood the cabin from the cockpit--which is not at all what I said. I mentioned it as an added possibility.

It's a possibility worth attempting as a last resort. That is, before bailing out of the boat. If you're putting out a stove-top fire with a fire blanket, then you're certainly not in a bad enough spot to be considering bailing off the boat.


Your arguments are based on the risks associated with CO2--and I agree that there are some. You shouldn't simply cast aside the risks of allowing the boat to continue to burn and having to abandon ship.

It's not "BAD BAD BAD advice" it's advice worth trying before abandoning ship. If the conditions are bad enough that you need to leave the cockpit, it's worth trying to flood it with CO2. It's one more tool in the box.

All that being said, CO2 is still my extinguisher of choice for extinguishing a fire in a sailboat...or any compartment fire for that reason. It doesn't further-hamper visibility, it's clean, and it avoids needless damage.

If you're docked, just leave the boat. If you're 1000 miles off shore and it's the last ditch effort before abandoning ship? It's worth a shot.

But again, what do I know?

(Disclaimer: I know next to nothing about sailing, but this topic does happen to fall into my wheelhouse)

[a64pilot]

Halon is still the best, and likely a mix of 1211 and 1301 Halon is preferable. 1211 I believe is a gas and is what most people think of when they hear Halon, 1301 is a wetting agent.
A source of halon fire extinguishers

https://www.aircraftspruce.com/search/search.php
On edit, I got the Halon numbers backwards

http://www.fireprotection.org.nz/inf...w-does-it-work

Finally I believe the FAA requires and only allows Halon on aircraft for fire extinguishing, it does no good if you suffocate the pilot or incapacitate him, and Halon does neither

However if you have a phobia against Halon, then Halotron is a good substitute, it works, just takes twice as much or is half as effective however you want to argue that.
I got my 10 lb Halotron at a restaurant supply place on line, so shop around
Fire blanket near but not in the Galley is cheap and supposedly effective, I’ve not used one myself, but can’t see why it wouldn’t work.
Fire blanket https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
But finally don’t forget good ole plain water, if the fire happens to get into upholstery or wood, water is exceptionally effective. I have a 50’ hose that I use for wash down that I can grab quickly if needed, in my case it’s plumbed into the fresh water system, but raw water would just as effective.

[xxxxx]

Originally Posted by a64pilot

Halon is still the best, and likely a mix of 1211 and 1301 Halon is preferable. 1211 I believe is a gas and is what most people think of when they hear Halon, 1301 is a wetting agent.
A source of halon fire extinguishers

https://www.aircraftspruce.com/search/search.php
On edit, I got the Halon numbers backwards

What is Halon and How Does it Work?

Finally I believe the FAA requires and only allows Halon on aircraft for fire extinguishing, it does no good if you suffocate the pilot or incapacitate him, and Halon does neither

However if you have a phobia against Halon, then Halotron is a good substitute, it works, just takes twice as much or is half as effective however you want to argue that.
I got my 10 lb Halotron at a restaurant supply place on line, so shop around
Fire blanket near but not in the Galley is cheap and supposedly effective, I’ve not used one myself, but can’t see why it wouldn’t work.
Fire blanket https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
But finally don’t forget good ole plain water, if the fire happens to get into upholstery or wood, water is exceptionally effective. I have a 50’ hose that I use for wash down that I can grab quickly if needed, in my case it’s plumbed into the fresh water system, but raw water would just as effective.

Halon is effective but illegal as of the mid-90s in most of the world as part of the Montreal Protocol.

It's banned in Canada, most of Europe, Australia, New Zealand, etc.

Aircraft are excepted due to the critical nature. So is military use.

Fire blankets work very very well. There's a bunch of public education videos online showing how well. Here's one: https://youtu.be/Il1JGc6Look

Keep in mind if you remove that blanket before the burning material has cooled, it will autoignite when it meets fresh air.

[rslifkin]

There are clean agent systems far safer than CO2. And Halon isn't the only choice there. FM-200 and Novec 1230 are both usable in a marine engine room. And both have a reasonable safety window between the concentration required to extinguish a fire and the concentration that will kill a person. So as long as the system is properly sized, it's not a death sentence if it gets dumped with a person in the engine room.

[tkeithlu]

Obviously, I agree with a lot of what XXXXX has to say. I do speak with at least a bit of understanding, given a history of being a University Fire Marshal, extinguisher technician, and fire extinguisher instructor. Halon's great, I agree, but CO2 is vastly cheaper, allowing you to afford CO2 in larger quantities that Halon. I own a 20 pound Halon extinguisher, in my boat, but that sucker cost $350 when I bought it. My 40 pounds of CO2 bottles cost less than $100 used.

A physiological note. Neither Halon nor CO2 will support life, but CO2 does have the peculiar property of causing you to want to breathe. When you hold your breath and desperately want to breathe, it is not lack of oxygen but the build up of carbon dioxide that gives you that sensation. I'm not sure what it feels like to breathe Halon. I don't recommend either.

[a64pilot]

The amount of Halon needed to completely extinguish a fire is no where near the amount that it takes suffocate you, there is a large gap, that’s why it’s used in confined areas that you may not be able to open a door and walk out of, like a cockpit or an armored vehicle.

However the min concentration of CO2 for a flooding agent is 34% and that amount is lethal.
At half that amount 17%, you have 1 min of consciousness to get out, then you die. Even at 7 to 10% it’s bad, real bad
https://www.epa.gov/snap/carbon-diox...xamining-risks

Read the paragraph of Life Safety Considerations, I knew it was lethal, but I didn’t know it was THAT lethal.

[rslifkin]

a64pilot has it nailed for why I don't like CO2 as an extinguishing agent. And the extinguishing concentration thing is also why I think that outside of places with lots of fragile electronics, portable clean agent extinguishers are also fairly useless. They'll knock a fire down, but unless discharged into a small enough space to maintain a decent concentration, re-ignition can be an issue. Dry chem will blanket to prevent re-ignition, while water or foam will provide cooling to help with that.

[xxxxx]

First, I want to correct something I said earlier. CO2 is effective for BC fires, not ABC fires. CO2 is effective on class A if you smother at high concentrations.

Neither the USCG nor Transport Canada require A-class extinguishers. They require only B-class. For class-A fires, I'd use water as a64pilot recommended.

The majority of fires on boats are electrical or engine related: https://www.boatus.com/magazine/2015...boat-fires.asp

OP, you will find extinguisher requirements in Chapter 12 of NFPA 302: Standard for Pleasure and Commercial Motor Craft. This is includes a sailboat with an engine (both inboard and outboard).

This standard represents the very best industry practices and they are written by a technical committee comprised of 41 stakeholders from various backgrounds. These are recommendations, but not laws. Some of the members sitting on this technical committee include representatives from:

• ABYC
• USCG
• Fire Departments
• Manufacturers
• Insurance companies

To save you some legwork, and to make sure all readers are getting the best advice, I've attached and highlighted the excerpts as they pertain to fire extinguishers.

You'll note that using a portable CO2 extinguisher is specifically referenced for use as a flooding agent in engine compartment fires. This is because it works. Appendix A has explanatory material.

It's freely accessible at NFPA.org: https://nfpa.org/codes-and-standards...etail?code=302