Features October 2017 Issue

Fire Extinguisher Tips for Cruising Sailors

Meeting the minimum is not enough.

While portable dry chemical fire extinguishers are a common sight aboard any sailboat, their installation, upkeep, and use is almost sinful. During marine surveys I’ve asked boat owners how long they think a typical BC-I portable unit will last when fighting a fire and have received answers ranging from “about 20 minutes” to “until the fire is put out”—scary, when you consider that the correct answer is around 10 seconds of continuous use.

Routine fire extinguisher inspections are crucial to ensure proper operation when needed. Your first check should be verifying you have the correct number and type of Coast Guard approved extinguishers onboard for your particular boat (see table). These standards are the MINIMUM and it’s always good to have additional units onboard. Extinguishers should be located in easily visible locations near the galley, engine compartment and all living spaces. A good rule of thumb is that you should never have to travel more than half the length of your boat to reach an extinguisher. Although not preferred, if you have to mount an extinguisher in a locker or cabinet, be sure to install a label or placard outside the cabinet indicating a fire extinguisher is located inside.

A common problem I see is having the correct number of fire extinguishers onboard, but locating all of them below decks where a galley fire could prevent access from the helm. Sailboats are particularly susceptible in this regard, since the galley is usually near the companionway. Always mount an extinguisher in the cockpit area, where it’s available to the helmsman the minute a fire is discovered.

jury-rigged “fixed” system
1. This jury-rigged “fixed” system blocks the port to the engine space, inhibitting the ability to fight an engine-room fire.

2. A wasp’s nest in this fire extinguisher suggests that routine monthly inspections were hardly routine.

3. An extinguisher in a locker is a last resort. If you decide to do something like this, be sure to clearly label the outside of the locker door.

Portable fire extinguishers have different maintenance schedules based on their type and extinguishing agent. Inspect yours monthly for loss of pressure, corrosion, damaged mounting brackets, clogged nozzles, etc. It’s also recommended that units be professionally inspected and tagged annually.

Unless you have a fixed, automatic extinguisher installed in the engine compartment, installation of a “fire port” is highly recommended. A fire or discharge port allows you to discharge a suitably sized “clean agent” portable fire extinguisher (i.e. CO2, Halotron, FM-200, FE-241) directly into the engine compartment without opening any access panels. A fire port must be sized to fit the portable fire extinguisher discharge nozzle, so the extinguisher can be used as the maker recommends. In my view, these ports are often too small to get the job done.

Using a clean agent extinguisher. for engine space fires is important. The dry chemicals in standard extinguishers is corrosive and hard to remove afterwards. It can actually cause more damage to the engine than the fire itself. A clean agent extinghisher smothers the fire by flooding the engine compartment, while dry chemical units have to be aimed directly at the base of the fire to be effective.

Capt. Frank Lanier is an accredited marine surveyor with over 30 years of experience in the marine industry. His website is www.captfklanier.com.

Comments (3)

After a US Sailing Safety at Sea seminar I am a big fan of fire blankets for galley fires: Instant out, no mess, can resume cooking, reusable, never expires, hangs with galley tools or towels, less than $20, covers the fire to reduce overhead involvement, and most important - allows you to remain in the cabin to monitor the situation.

On a side note there has been a growing problem of onboard fires caused by laptops with lithium batteries on constant 'charge'.

Posted by: DanoMielke | October 9, 2017 9:01 AM    Report this comment

A dry chemical extinguisher could cause quite a bit of damage to your diesel. So you would have extinguished the fire just to disable your boat. I would use CO2 in the Engine Port and an automatic CO2 as well.

CO2 has the benefit of being able to displace the atmosphere in the engine compartment and cool it down as well as prevent re-ignition. Of course after you completely discharge the CO2 extinguisher; GET OUT!!! The CO2 can displace the atmosphere in you boat especially if it is somewhat small. Once you exit the saloon DO NOT RE-ENTER until you open some hatches if you have outside opening hatches and ventilate the saloon; a bilge ventilation system on a separate panel in the cockpit may be a prudent upgrade. Venting the bilge will vent the boat from the bottom up.

Using dry chemical in a closed space is not recommended. It is toxic. Just a few second burst can fill completely the saloon or cabin with a suspension of toxic dust. This can also disorient and blind the user.

To just completely empty a dry chemical extinguisher in order to adequately blanket the fire AND cool it down will completely fill the boat with an extremely fine powder that would be as dangerous as a smoke filled environment. There is an argument for completely emptying the Dry Chemical extinguisher on the fire. Why?

Dry Chemical uses a specially fluidized and siliconized monoammonium phosphate powder. It also produces CO2 when in contact with fire and the propellant is nitrogen which will displace the oxygen in the compartment as well.

Selecting a Fire Extinguisher is not easy. Fires may start from diesel, gas or electricity but they could always end with the plastic or wood being burned to the waterline.

Before an extinguisher is even used; power, gas and fuel must cut off. Of course you should have the ability to transmit a Mayday without power. Isolated LiPO batteries or a portable VHF comes to mind.

I am not debating the merits of Dry Chemical vs CO2. You must come up with that answer on your own.

Posted by: rav555 | October 8, 2017 9:32 AM    Report this comment

A slight clarification. It is also a very good idea to have an extinguisher visible from anywhere in the boat. A panicked person, particularly a guest, should see one anytime there is a need. Also, since galley fires are most common, and can block access to either side, it is best to have one on each side of the galley.

"Clean Agent" for the Engine spaces, "Dry Chemical" for the Galley and paint locker.

Posted by: Umpqua Chief | September 26, 2017 11:44 AM    Report this comment

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