Be Ready to Fight a Fire
A properly equipped and maintained suppression system can prevent an engine-room blaze from destroying your boat. "Hands-On Sailor" from our November 2009 issue
The cry "Fire on board!" ranks right up there with "Crew overboard!" or "We're sinking!" as among the worst things a cruising skipper can hear. Despite that, many cruising boats are ill prepared if a fire does strike. In fact, the vast majority of sailboats, unless they were built within the last several years, aren't compliant with existing American Boat & Yacht Council or European Union standards that address fire suppression. If you own an older boat, you should take stock of the fire extinguishers and other fire-suppression equipment you have on board, then make the necessary upgrades so that if a blaze breaks out, you're ready to fight it.
Onboard fires fall into two general categories: open fires, which may occur at a galley stove or in the main salon, and fires that start in closed spaces, such as your engine compartment. Both are dangerous, but fires that start in the engine space are more common, so preparing to face those will be the focus of this article.
Proper fire-suppression equipment comes in several tiers of sophistication, depending on a boat owner's budget and desires. But in general, "clean agent" systems are recommended for most engine compartments. We'll get to those in a minute, but first, it's important to realize that in any firefighting situation, the last thing you want to do is add oxygen to the fire or risk having the extinguishing agent dissipate into an area other than where the fire is located. So, for example, if your boat doesn't have a fixed-mounted system in its engine compartment and a fire breaks out, you definitely don't want to open the compartment's cover to see what's going on. The best method for attacking such a fire is to inject the extinguishing agent into the space without opening any access panels.
For boats without a fixed-mounted fire-suppression system, and this includes many small to medium cruisers, the A.B.Y.C. adopted in 2000 what had been an International Standards Organization requirement in Europe for some time. Now A.B.Y.C. standard A-4 requires all engine compartments to have a fire-extinguisher port; typically, it's located under a companionway step on the engine-box cover. In the event of a fire, you grab a nearby extinguisher, open the small port, insert the nozzle, and fire off the canister.
If you own an older boat, the addition of such a port is an easy Saturday-morning project that requires only a properly sized hole saw and the installation of a ready-made port. Ports are available from marine distributors and cost about $13.
Keep in mind that simply having the port isn't enough. It's not reasonable to assume that everyone on board will know what the function of this port is, especially in the panic that accompanies any onboard fire. Therefore, the A.B.Y.C. also requires the posting of a label that provides the requisite instructions on how to use the port and an extinguisher in the event of a fire. A prudent skipper reviews these instructions with crewmembers as part of any safety briefing.
Note that boatbuilders outside of the United States often favor a simple graphic to indicate, say, the function of a port or to warn of moving machinery inside a compartment rather than providing a label describing in words what to do in the event of a fire.
Once you've installed a port, or if you have a boat already equipped with a port, you need to be sure that the extinguisher located near it is sized correctly and that its nozzle fits through the hole and into the engine compartment.
A.B.Y.C. standard A-4 provides some guidance here, as well. To select the properly sized extinguisher, you need to determine your engine space's net volume. According to the standards, the net compartment volume is considered the gross volume minus the volume of any permanently installed tankage. On most sailboats, tanks aren't installed in the same compartment as the engine, so the calculation is usually just the length times the width times the height of your engine space, measured in feet.
You don't need to be super precise with these measurements, but you should always err on the side of caution. So if you end up with a measurement that's greater than the actual volume, no problem: Using more extinguishing agent than is actually required isn't necessarily a bad thing. It helps to ensure that enough extinguishing agent does, in fact, get into-and stay-in the compartment in question. Some leakage is likely, and it's hard to avoid.
Once the net compartment size is determined, put a label indicating the value in the engine room; this is now an A.B.Y.C. requirement, too.