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More Is Better

So your boat satisfies the official requirements for onboard firefighting?
Maybe that’s not enough.

When was the last time you had a fire aboard your boat? I’m guessing never: Yacht fires aren’t common—according to the U.S. Coast Guard, fire accounted for only about 6.5 percent of reported boating accidents in 2014, 5 percent of injuries, and less than 1 percent of deaths. (You’ll find the specific numbers in 2014 Recreational Boating Statistics, available at I guess that that’s not many fires, but then again if you find flames licking at your Top-Siders, numbers won’t matter—fire extinguishers will. Check yours now, and think about adding more. Maybe you’ll never use them, but should the need some day arise, you’ll be glad you coughed up the extra cash.

And bear in mind one very important thing. While I’ve never had a serious fire on board, friends of mine have, and they all say the same thing: The situation can get very bad, very quickly. There’s a lot of flammable material on a boat, and once fire gets a foothold you’ll be facing a hot, smokey situation with possibly toxic fumes. And if the flames ignite the fiberglass, chances are you’re looking at an abandon-ship situation. (Commercial and military fiberglass boats are usually laid-up with flame-retardant resin, but it’s rare in yachts.) If you don’t have a fully charged extinguisher immediately at hand, in the time it takes to fetch one, the fire may well go beyond both the capabilities of the equipment most of us carry and our firefighting skills.

Rules and Regs

Rules promulgated by the Coast Guard require boats under 26 feet to carry a single approved Class B-I extinguisher; boats up to 40 feet, two B-Is or one B-II; up to 65 feet, three B-Is or a B-I and a B-II. (B-I extinguishers contain at least two pounds of dry chemical, which discharges in about 10 seconds; B-IIs contain at least 10 pounds of agent and last about twice as long.) A fixed fire-extinguishing system in an engine room can count as a stand-in for a B-I. So even a 65-footer will be legal with just two B-I extinguishers, or a single B-II, if there’s a fixed system in the engine room. Vessels over 65 feet are required to carry B-II extinguishers, the number determined by tonnage and horsepower. (See the Code of Federal Regulations Title 46, Chapter I, Subchapter C, Part 25 for more details; find it online at

BoatU.S., the American Boat and Yacht Council, the National Fire Protection Association, and many surveyors and insurance companies suggest carrying extra extinguishers, however. How many extra? I follow the recommendations of NFPA 302, Fire Protection Standard for Pleasure and Commercial Motor Craft, which calls for one B-I extinguisher aboard boats under 16 feet, two B-Is on boats from 16 to 26 feet, three B-Is on board boats up to 40 feet, and four on boats up to 65 feet. A fixed extinguisher in the engine room, or a portable with a dedicated clean agent, e.g., Halotron, FE-227, or CO2, for discharging into an engine room through a fire port, is also required. If you don’t have an automatic fire-extinguishing system in your ER, by the way, I suggest you invest in one. And, as with the federal rules, NFPA standards call for more, and bigger, extinguishers aboard boats over 65 feet. (You can read NFPA 302 online at; click on “Codes and Standards.” You’ll have to register, but it’s free.) I also suggest you take these standards to heart.

Complications While Shopping

Just to make things more confusing, all B-I and B-II fire extinguishers are not created equal. Some have more extinguishing agent than others, some are UL-rated for only class B (flammable liquids) and C (electrical) fires, while others also cover class-A (combustible solids) fires. Along with Coast Guard approval on the extinguisher’s label, look for the UL rating; it’ll be something like “1A:10B:C” or “5B:C”. Higher numbers mean more capability, but C never has a number—the letter simply attests to the agent’s non-conductivity of electricity. There are also class D fires, which involve combustible metals—aboard a yacht, the most likely scenario entails a flare fired accidentally, although temperatures can actually get hot enough during more conventional fires to ignite metals, a bad situation that virtually dictates abandoning ship—and class K fires, which involve cooking oils and fats. (NFPA 10, Standard for Portable Fire Extinguishers, is worth a read. It’s also free on

Usually, extinguishers that include the A rating replace the sodium bicarbonate extinguishing agent used in most B- and C-rated models with monoammonium phosphate, often called ABC, tri-class, or multipurpose dry chemical; it’s yellow—sodium bicarbonate is white—but with luck, you’ll never see it. Monoammonium phosphate is acidic and corrosive, really hard to clean up, and can damage electronics. Moreover, if it gets wet, it often hydrolyzes into phosphoric acid. Great stuff, huh? But most boat fires involve class-A fuels; maybe an electrical short or fuel leak starts the fire, but at some point joinery, structure, upholstery, and other materials begin burning, so ABC is what you want in most cases. Deal with the cleanup once the fire’s out, onerous though it may be. NFPA requires ABC-rated portables for most boats, although I’d splurge on a clean-agent portable instead, e.g., Halotron or FE-227, for the nav station and/or the master electrical panel. It’ll be way more expensive than dry chem, but cheaper than replacing the electronics.

A variety of  ER-based  units use Dupont FE-227, a “clean agent.”

A variety of ER-based units use Dupont FE-227, a “clean agent.”

Install Where?

Extinguishers should be mounted near the most likely site of a fire, but not where the fire may preclude their use. So where’s that? Insurance claims filed with BoatU.S., as analyzed in the association’s Seaworthy magazine, indicate that 55 percent of onboard fires result from electrical issues: 30 percent from DC shorts, 12 percent from faulty voltage regulators, and the rest from battery chargers, shore-power faults, and AC appliance issues. Overheating machinery caused another 24 percent, and fuel leaks, stove leaks (typically alcohol stoves, once common aboard yachts, but now rare), and “unknown” and “miscellaneous” issues account for the remaining blazes.

But hey, the Coast Guard stats I’ve already cited suggest that more than half of the boat fires in 2014 were fuel-related, not electrical-issue-related. Well, regardless of whose figures you believe, it’s clear that many fires start in the engine room or machinery spaces of our boats, so I suggest protecting these areas with automatic extinguishing systems that use gaseous “clean agents” that produce little or no collateral damage when deployed. And add automatic shutdown for diesels as well—most any diesel will run lustily on a clean firefighting agent; you want the stuff to stick around and quench the fire, not get burned as fuel by a diesel engine or engines.

And don’t forget. If your automatic system discharges and seemingly puts out the fire, resist the temptation to open the engine-room hatch prematurely to check on things in what amounts to a sealed compartment; the influx of fresh oxygen may reignite the fire. It’s always better to give an extinguishing agent plenty of time to work. And while you’re waiting you can call for help if necessary, make sure your crew members have all donned their PFDs, and establish a clear and safe exit from the boat if that should be called for. (Read more about fixed fire-extinguishing systems here ▶)

Nitty and Gritty

Here are a few more nitty-gritty suggestions. Mount an ABC portable extinguisher at each steering station, in the galley (away from the stove), in each stateroom, in the cockpit, and outside the engine room. Mount smoke and CO detectors that address likely spaces, too, if you don’t have them already. If possible, install a fire port in your engine-room door ($18 at and mount a clean-agent portable next to it; this will be the backup for your fixed system.

And remember. You always want to err on the side of more extinguishers; they don’t cost much if you buy disposables—a Kidde Mariner 110, rated 1A;10B:C and USCG B-I, with a six-year warranty, for example, costs about $40 at West Marine. Refillables cost a little more, but have metal, rather than plastic, valves; I think they’re worth the extra money. (Note that there was a recall of some Kidde Mariner 10, 110, 5, and 5G fire extinguishers in March 2015. Kidde has a link to the related Product Safety Notice on its Web site, After all, when it comes to fire on board, why take chances? More is better.

2018 Boatyard rule

Where’s the Life Raft?

About 20 years ago, I wrote an article about an aluminum megayacht that burned in a Florida boatyard. The fire burst though the upper decks and out of the side of the yacht, also destroying a big wooden schooner on the other side of the float. The fire marshal involved thought the cause was a 150-watt overhead halogen light that was left on long enough to start a smoldering fire in the adjoining aluminum-honeycomb joinery; when the fire erupted into the open, it was already a full-blown blaze.

Eyewitnesses said the time from the moment they first saw the fire until the yacht was destroyed was only a few minutes; the crew couldn’t make it onto the floating dock and had to jump overboard, where they were rescued by a passing boat. No one was injured.

Lucky they were not at sea: The fire consumed the upper deck, where the life rafts were stowed; they were gone almost immediately, according to a captain who saw the fire. He said the sight convinced him to relocate rafts and safety gear on his own boat to a spot where they would be more likely to survive long enough to do some good.

The captain’s point, I think, is well taken: Mount your life raft where a fire’s least likely to reach it—maybe the stern platform is the best spot, or on the foredeck. Rafts and safety gear on the flying bridge or sundeck may wind up engulfed in flame before you have a chance to get to them. Try to predict what would happen if a fire were to break out in your engine room—the most likely spot. Don’t stow PFDs under a berth or settee directly over the ER, but keep them in a spot that’s going to be predictably easy to get to should you ultimately need to abandon ship. A little planning may keep a fire on board from turning into a total tragedy.

2018 Boatyard rule

Ready for a Fight

Having fire extinguishers aboard, and plenty of them, is an imperative for safe boating. But like any piece of onboard equipment, extinguishers require regular maintenance. Here are six things you should be doing to ensure yours are ready for duty.

1. Inspect it for dents, rust, or chemical deposits on a monthly basis as these are signs that may lead to a small leak that over time will render the device useless.

2. Shake dry chemical extinguishers once a month to prevent settling and hardening at the bottom of the canister.

3. Replace or recharge your extinguishers after even a short use. In fact, even if you only used it for a second and the gauge still reads full, it still needs to be replaced.

4. Make sure access to all extinguishers is unimpeded. As the boating season wears on, your lazarette may become cluttered (no judgments here); make sure it gets squared away to ensure your guests or crew can easily find the extinguishers.

5. Make sure the extinguisher is fully charged; this is made easier by getting units that have a gauge on the top. If you notice the level dropping, it’s time time to replace or recharge.

6. Have a professional extinguisher maintenance contractor perform annual inspections. Mark your calendar—it’s worth it.

— Daniel Harding Jr.

This article originally appeared in the January 2016 issue of Power & Motoryacht magazine.