Fire In The Hole

How to keep your boat from going up in smoke.

February 6, 2009

“Fire!” is the last thing you want to hear while afloat. Many onboard fires start in the engine room, the place where volatile fuel and electrical connections abound. But other than the basic fire extinguishing systems, what options will warn you of or extinguish fires? Let’s take a look.


There’s nothing better than an early warning system, and Sea-Fire ($156; has recently introduced one with a new multifunction control panel. With the addition of a couple of temperature sensors ($145 each), it can be used as a standalone display that will detect rising temperatures in the engine room. It flashes a light and sounds an alarm, alerting you of an impending fire.



Installed suppression systems come in three types — manual, automatic, and a combination of the two. The best? A fully automatic system. If you’re not onboard or if a fire starts in the engine room, a manual system can’t work. Also, an overly excited owner or crewman might be too quick to activate a combo unit, instead of putting out the fire by simply shutting down the engine or using a well-aimed blast from a handheld extinguisher. An installed automatic (bottle) fire suppression system is always ready to go off when the engine room temps rise above a specified level. Prices vary with the size of the engine room and the type of extinguishing agent (HFC-227ea for use around people, or FE-241 in unoccupied areas only) — figure on a modest $200 to $300 for a 25-cubic-foot compartment, going up to thousands for your 100′ megayacht. Longtime established suppliers of these systems are Sea-Fire and Fireboy (

Shut Down


One of the more important accessories for a suppression system is the automatic engine shutdown module — a required add-on for boats with diesel power. Shutdown systems typically turn off not only the engine but also engine room blowers (which bring fresh oxygen to a fire), generators, and powered dampers or louvers. Depending on the number of circuits involved, these modules, available from Sea-Fire and Fireboy, cost $300 to $600.

Look, But Don’t Feed

If your boat is equipped with an engine box instead of an engine room, check out a simple, easily installed gadget called the Fire Port ( Instead of popping open the engine cover to see if there’s a fire (and thus feeding it oxygen), inspect the engine through this clear PVC vinyl port. If you see flames, jam the head of an extinguisher into the port and pull the trigger.



Another product for smaller confined areas is the single-use Fire Foe, an extinguisher in a tube from Sea-Fire. This permanently mounted extinguisher comes in five sizes ($495 to $895) for engine rooms as large as 130 cubic feet. It’s easy to install, and when the temps get too hot, it bursts and sprays Envirogel, an extinguishing agent. Oh yeah, let’s not forget your plain old everyday handheld extinguishers. Coast Guard regs require as many as two B-I (or one B-II) units for boats as large as 40′ without an installed system. If you have the bucks, get a rechargeable one (like the Kidde Pro Series, $40; Look for the USCG-approved label that also covers the mounting bracket — and make a routine check of the status gauge on each extinguisher before getting underway. “In the red” means it’s dead.


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