It is almost time for boating season! While we all want to get out on the water and start enjoying the warm waters of Spring and Summer as soon as possible, there is a great deal of preparation to be done beforehand. Vessel maintenance and safety checks are important, but so is making sure that you’re fully aware and mentally prepared for anything – knowledge as they say, is power. No matter how experienced you are, the sea is unpredictable and anything could happen at any time. Whenever out and enjoying your diesel vessel, being mindful of safety procedures is paramount and no contingency plan is too excessive. One of the most dangerous threats to any vessel out at sea is the risk of fire, particularly for those who rely on diesel engines for their propulsion needs. By understanding the causes of marine fires, they will be easier for you to prevent.
It is unlikely that you’ve ever encountered a serious fire on your vessel, but that doesn’t mean you shouldn’t be prepared for the eventuality – adding to the danger, these things tend to happen when you least expect them. Despite the irony of being surrounded by water, most vessels are filled with highly flammable materials, so it doesn’t take long at all for even the smallest fire to grow into a serious problem. Once those flames reach the fiberglass construction of your hull, the toxic fumes and smoke alone will likely be enough to warrant abandoning ship, let alone the structural damage caused by the quickly-spreading blaze. Fires on recreational diesel vessels are not particularly common – in 2014, the US Coast Guard reported that fire was the cause of about 6.5% of boating accidents, 5% of injuries, and less than 1% of boater deaths. Despite their rarity, marine diesel fires are incredibly destructive when they do occur, spreading out of control almost immediately.
Understanding the causes of fires aboard recreational diesel vessels and how to prevent them is crucial to keeping you, your loved ones, and your vessel safe this and every boating season. These types of incidents are typically caused by malfunctioning or poorly maintained equipment, and can be easily avoided by having a professional diesel technician perform maintenance on your engine and generator regularly, especially at the beginning of the season when your vessel has likely been under a tarp and unused for several months – just as many problems can arise for your vessel from being sedentary as from being active, and these are usually easier to ignore or miss. Due to the high operating temperatures of diesel engines, your vessel’s engine room is the most common origin point for fires at sea. Insurance claims over the past few years seem to indicate that overheating machinery accounts for about 24% of all onboard fires, nearly an entire quarter of incidents reported.
Of all diesel engine fires, the most common and hazardous type are scavenge fires. These devastating and unpredictable events can be catastrophic, causing even the most capable vessel to capsize in moments. The scavenger is the component of all combustion engines that pushes the exhausted gas-charge from the cylinder and draws in fresh air and fuel for the next cycle. Occasionally, carbonized lube oil, unburnt fuel, or other residual byproduct particles of the engine’s combustion accumulate in the scavenger space. Now trapped with an ignition source and limited air supply, these carbon particles become heated to a combustion point. At this point, all it takes is one spark to result in a massive fire that can quickly spread out of control. Though many factors involved are unpredictable, scavenge fires are largely avoidable as they are usually due to maintenance issues like improper setting of fuel timing, choked off exhaust, defective injectors, usage of low-grade fuels, insufficient scavenge air supply, defective piston rings or cylinder liners, or incorrect engine lubrication. There are also many indications that a scavenge fire may occur in the future, such as high exhaust temperature, smoke from the scavenge drains, or reduction of rpm and loss of engine power. Most of these issues can be prevented with regular maintenance.
Even with a properly maintained engine, it is still important to take the other necessary precautions to heart. Having a fire extinguisher onboard is imperative, but making sure it is ready for use in case of an emergency is just as important. Before every voyage, make sure that the extinguisher is easily accessible, free of dents or rust, and fully charged. It is also wise to have an annual inspection scheduled with a professional extinguisher maintenance contractor. Obviously, the best way to deal with an engine fire aboard your diesel vessel is to prevent it from happening in the first place. We all know how intense the excitement of getting back out on the water can be, but taking a moment to make sure that all of your potential maintenance issues have been addressed and that your basic safety procedures have all been followed will greatly reduce the chances of engine fires or other dangerous scenarios.
