Nothing is more frightening than a fire at sea. In 22 years of sailing all over the world in a wide variety of boats, I've only had to deploy fire extinguishers twice. Both were small fires, caught early and easily put out
My other fire was aboard an Ocean 71 that I delivered from Newport, RI, to Stockholm. We were in the Baltic, ripping along under spinnaker when we heard a sound like the engine turning over. I went below and opened the engine room door. What had been a small fire suddenly became a much larger fire, fed by the tasty oxygen I had just let in. This time I reacted quickly and grabbed the hefty 20-pound, dry-chemical extinguisher mounted on the engine room door. It was obvious that the fire was emanating from the starter motor. I took my time and aimed carefully at the base. Then I pulled the pin and fired. To my surprise and relief, the flames died out immediately. After I cleaned up another colossal mess, I traced the source of the fire. Somehow, probably through an electrical short, the starter motor had engaged. This created a lot of heat that eventually ignited the wires leading to the alternator. It was a freak accident and luckily I reacted before the fire spread to the batteries. The damage was minimal.
My experiences represent the two most common areas where fires originate aboard sailboats, the galley and the engine room. Other causes of fire may be faulty, or just old, wiring, cabin heaters, electric motors, lightning, overhead power lines, and of course, flammable fuel sources. Gasoline and propane are the two most dangerous items on any boat and when a fire results from an explosion it is almost always too late to do anything except grab a PFD and head for the water.
Onboard fires fall into three classes: A, B, and C, identified by the material that is fueling the flames.
Class A: Ordinary Combustibles, including wood, paper, foam, fiberglass, rubber, some plastics, and other materials that burn easily. Class A fires are best extinguished with water.
Class B: Flammable Liquids, including gasoline, diesel fuel, propane, paints, varnishes, oils, greases, and flammable gases. Class B fires can be extinguished by smothering with a fire blanket, or with type B-I or B-II extinguisher.
Class C: Electrical fires, including any energized electrical equipment. Class C fires are best extinguished with sodium carbonate (dry chemical), carbon dioxide (which can be dangerous to humans) or new Halon alternatives like FE-241 and FM-200.
Logically, fire extinguishers are also classified with the same system. Most sailboats rely on portable extinguishers. It doesn't make any sense but to spend a few extra dollars for a tri-class (ABC) dry-powder extinguisher that can be used on all types of fires. The Coast Guard also rates extinguishers as either B-I or B-II based on how much extinguishing agent they contain according to weight. B-I extinguishers need at least two pounds of dry-chemical agent, or four pounds of CO 2. B-II extinguishers must have 10 pounds of dry chemical and 15 pounds of CO-2. The Coast Guard has minimum requirements for recreational boats and they are just that—minimal. For boats less than 26 feet, one B-I extinguisher is required. Boats 26 feet to 40 feet need either two B-Is or one B-II. Boats over 40 feet need three type B-Is, or one B-1 and one B-II. Most portable dry-chemical models are usually in the two to three pound range. These small, B-I extinguishers will discharge for approximately eight to10-second and have a maximum range of 10 feet. A five-pound B -1 extinguisher discharges for 13 to 15 seconds and has a range of about 15 feet.
I am like Shere Khan in Kipling's Jungle Books—I take fire seriously. On my 44-foot ketch, I have six type B-I, 2.5 pound, tri-class extinguishers, twice the Coast Guard requirement. They cost less than $20 each. I have one in the stern lazarette, one on the bulkhead by the companionway, one across from the galley, one in the engine room, and one in each sleeping cabin. I don't want to search for an extinguisher when a fire breaks out. I also have a fire blanket in the galley, in a locker away from the stove. The Coast Guard requires that all extinguishers have a pressure gauge but it is your responsibility to make sure they're current.
Prior to 1994 many larger sailboats were fitted with automatic Halon systems, especially in the engine room. For years Halon was an effective fire fighting agent. The system was triggered by heat and could be used on any type of fire. Because it was automatic, the engine room door remained closed limiting the available oxygen needed to fuel the fire. It left little residual damage, as opposed to the huge mess made by powder extinguishers. Unfortunately, Halon was deemed environmentally dangerous since it was contributing to the hole in the ozone layer, and it was banned from production in the US. Capitalism spawned a new, safe, Halon alternative, FE-241, which has many of the same attributes of Halon, but it's just not as compact. Fireboy markets the best-known system and while these units are expensive, they feature heat-activated discharge and a panel gauge that indicates the level of charge.
It can't be overemphasized that fire on a boat is a serious problem. Your world is burning, help is likely a long way away and you have nowhere to go except overboard. At the risk of stating the obvious, the best protection is avoiding fires to begin with. Routine maintenance and good seamanship can all but eliminate fire risk. Still, fires are unavoidable and you must be prepared to deal with the situation at hand.
Remember, if you have a class A fire, nothing is more effective than quick action with a bucket of seawater. It may seem odd at first to be throwing water "into" your boat, but for this very purpose you should keep a bucket with a lanyard handy. The advantage of water in this type of fire is that it tends to cool much of the surrounding area, preventing a smoldering fire from restarting. Quick action and cool thinking is the key to fighting all fires successfully.
Naturally, if you're sailing near shore where quick help may be available, the first step is to notify the Coast Guard on the VHF radio. If you are wary of going below, use your cell phone to call 911. Fiberglass boats burn quickly and at extreme temperatures. They also give off noxious fumes. If you smell the hull burning, you should take immediate steps to abandon ship. Once the hull is burning, the fuel tanks can't be far behind. If you have time, launch the dinghy and the liferaft and move away from the burning vessel as quickly as possible.
Almost all fires begin small and if you react quickly you can contain and eventually extinguish them. Remember, however, that even if you're just 10 miles offshore it is unlikely that the Coast Guard or anyone else will be able to assist you—you have to assist yourself. Your time is better spent fighting the fire than trying to find help.
The first step is to keep the fire in a confined space. Your instinct is to open ports and hatches—don't. Fires need oxygen, and ventilation only makes matters worse. In fact, if you can close a hatch or door, you will help suffocate the fire. Also, stop the boat immediately, or at least head downwind to decrease the apparent wind since the boat's forward motion fans the fire. If possible, try to position the boat so that the wind blows the fire overboard. Like most emergencies, teamwork is critical. While you are containing the fire, have your mate or crew handle the boat. They should also be preparing to abandon ship, just in case. If the fire is electrical, and not near the battery compartment, take a moment to disconnect the batteries. Naturally this is a prudent move in any fire.
Sometimes, the best way to deal with a fire, is to toss whatever is burning over the side. Do this after deploying an extinguisher. By the way, fighting a fire on a boat is not the best time to learn to use an extinguisher. Just like you dutifully practice man-overboard drills, you should invest in a few cheap extinguishers and set them off. It is rather shocking to see how little agent they actually contain and how quickly they spend it. Your chances for success are a lot better if you are familiar with the equipment.
Once you have determined the likely source of the fire, pull the pin and aim the nozzle at the base of the flame. Use a series of short blasts, sweep from side to side, and have another extinguisher ready to go. Use your extinguishers carefully. Once they're gone your options are severely limited and the situation can quickly become very bleak.
A fire aboard, like most emergencies, requires immediate action. Having the right fire fighting equipment and knowing how to use it make the difference between saving your boat or sending it off to Valhalla.
Rules of Fire Fighting
Quick summary for fighting fires aboard:
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