Fire Extinguisher Confusion

[jen1722terry]

Hey Sailors!

We getting ready to sea-trial our old 31 with the new engine. Our insurer required a new survey, which we've completed. The surveyor and we discussed upgrading our fire extinguisher, which are presently 3, 5 lb., dry chemical units.

We'd like to replace one of the dry chemical units with one of the newer gas units to keep near the galley/engine cover. This would eliminate the possible damage from the dry chemicals. For cost and space reasons, we do not want to install an automatic system in the engine room, which would also require an auto-diesel shutoff unit. Instead, we will install a Vetus fire port in the engine cover so the new extinguisher can quickly be discharged into the engine room without opening the cover and feeding the fire. That's the easy part.

The confusion stems from the availability of different gases for the newer extinguishers: Halotron and some other post-Halon variants; Argon gas and maybe a few more. Also, warranties and recharge costs vary among the manufacturers.

So, our question is, has anyone gone through this thought process while upgrading there fire control and, if so, could you share any wisdom you've gleaned from the process?

Much appreciation, in advance.

Jenn and Terry

[Peter Nuss]

There really is not any "possible damage" with dry powder, they cause damage. Specially with electrical equipment, as the dust get into the device and you never clean that until it's too late to save it.

Dry chemical extinguishers contain ammonium phosphate or sulfate powders, that is an irritant to the eyes skin and lungs. It's corrosive and getting rid of the powder after use is problematic. It can not be dump in any area that is return to the environment, ie. any sewage pipe that does not go to a sewage treatment plant, or water way, etc. Also, clean up with water makes it even more corrosive and a bigger mess to clean up. I get rid of them on anything I own. Not worth the problems it can create on top of the fire damage and more so when the fire creates no damage and all you have is the damage the dry powder created. The other issue is the powder settles. It becomes hard and maybe, it will not work when you need it. I would think each year increases the chances of that bouncing around in a boat.

Halon is really the best way to go, but, you can not get it any more in the USA unless you are on a Navy ship. I think you can still get it in Canada though. Halotron is the better way to go. At least for the next few years till it's out lawed in 2030. The replacement for that will probably be less efficient, just as Halotron is to Halon.

Fire extinguishers, expensive cause they are worth it. Good luck with your project

[gates_cliff]

There are "clean fire extinguishers" , they're expensive comparatively but... probably worth it if you have to use it.

[Joe CD MS 300]

I also installed a fire port for the engine room. Also did not like the idea of an automated system with a diesel shut off. The halotron tank is a lot larger than your typical marine fire extinguisher but a gas extinguisher is the only type that works with a fire port. The tank is stored in the hanging locker. I don't recall considering other types of gases. It's been a few years. With Halotron and a fire port you are basically filling the engine room with the gas pushing out all of the oxygen. Not sure if the other gases work the same way Other types of extinguishers need to be aimed at the source of the fire. Can't really do that well through a fire port.

Good West Marine article:

https://www.westmarine.com/WestAdvisor/ ... inguishers

[tjr818]

What about CO-2 Fire extinguishers? Wouldn't they work through a fire port?

[Joe CD MS 300]

I don't know this from experience but I have heard there are thermal shock issues on a hot engine with co2 and it works better when pointed at the source of the flames. The typical hose fitting on a co2 may not fit though the fire port. Those issues pushed me in the direction of Halotron.

[Joe CD MS 300]

Duplicate post deleted

[jen1722terry]

Thanks to all for the thoughtful comments.

We're leaning towards the Fireboy argon gas units, with a smoke/fire sensor and alarm in the engine room and a fire port on the engine cover. That way the Fireboy can still be accessible for galley fires.

The Fireboys do have a much shorter warranty (3 yr. vs. 6 yr. for some of the halotron units). We plan to call the mfr. for info on service life and more testing info on the argon gas as compared to halotron.

Neat stuff, the argon. It's heavier than air and non-toxic, which seems good for the confined spaces of our CDs.

We can only budget one unit this year, than another next year for the V-berth. We plan to keep a dry-chem. unit in the lazarette only for backup plan until we can budget a third unit.

Thanks again. We launch in two weeks.

Jenn and Terry

[Joe CD MS 300]

Thinking back to when I was going through this decision process, I just recalled that it was unclear whether Halotron had USCG approval. I still keep three non Halotron extinguishers aboard just in case they are not. Don't think Argon was availableat the time. Here is a link to the USCG site re: extinguishers.

https://www.uscg.mil/hq/cg5/cg5214/fesys.asp

https://www.uscg.mil/hq/cg5/cg5214/fireca.asp

I did happen to get boarded for a USCG inspection with no issues. With Argon being a newer agent I think I would still keep the required number of clearly approved extinguishers aboard although I see on the Kiddie website that it is USCG approved. Forgot how complicated this issue was and how hard to get info.

[Pembquist]

My boat has an out of date Halon Automatic bottle in the engine compartment and I plan on replacing it with another automatic but I don't see adding an electronic engine shut down as being that practical. I guess the question is whether the diesel would suck all of the extinguishing agent overboard. I have thought idly about making the engine compartment more air tight and fire resistant, maybe lining it with something like this 3m product: http://www.aircraftspruce.com/catalog/a ... ll2000.php The rest of my extinguishers are dry chemical and I have 4.

[Lisa G.]

Here is a good article on Halon.
http://www.h3rcleanagents.com/support_faq_2.htm

Lisa
1981 CD30c Pochade