The Essentials of Living Aboard a Boat
Page 20
Since the fittings and hoses may also leak, it is critical to test the connections (often done with soapy water) and install a propane detection system with sensors in the lowest parts of the boat, as well as an alarm and emergency shutoff, so that if propane is detected, the passengers can be notified and the gas flow terminated.
It is surprising how many boaters do not follow these simple safety rules, or are even aware of the consequences, and it is agonizing whenever there is a story of an explosion caused by a propane leak. On the water, even great care cannot prevent all circumstances in which something might go wrong, whether it be a malfunction, a storm, or, as is often the case, a mistake. Adequate safety precautions and systems might be the difference between a safe outcome and a less desirable one.
This type of disaster could have happened to me one night when some friends and I were having a barbeque at anchor off of one of the Boston Harbor Islands. After we finished cooking, a passenger who was taking the barbeque off of the rail unscrewed the one-pound propane tank, went below, and placed it on the galley counter. I was down below and heard the tank still releasing gas. The safety mechanism on the tank had jammed open and propane had leaked for an unknown length of time. Knowing the risk, I had that tank off the boat in one or two seconds as if it were a grenade. I was very worried, since I did not know how much propane had already accumulated in the bilge. The boat never did explode, but had there been a propane bubble, it could have ignited at that time or sometime later. I consider myself lucky to have escaped this problem.
Alcohol Stoves
There are two kinds of alcohol stoves: pressurized and non-pressurized. Non-pressurized stoves are quite safe, but pressurized stoves can be quite dangerous. Pressurized alcohol stoves are known as “curtain burners.” My boat, like many other older boats that do not utilize propane or electricity for cooking, has such a stove.
Many boat owners do not like to use alcohol for various reasons: the added time spent to get the burners lit, the high initial flame, the low temperature cooking heat, and the fact that food can be tainted with the taste of alcohol fumes.
The reason for the nickname “curtain burner” is that pressurized alcohol, when being ignited, is pooled in the burner and lit. While it is heating the burner to allow for a traditional stove burn, it burns erratically and high. This flame can rise more than a foot above the stove. Lighting my stove on one occasion actually scorched the bottom of my curtains, and I ended up discharging a fire extinguisher—what a mess.
If you do use alcohol, store it properly and safely, and follow the lighting procedures. Move flammable items away from the flame and carefully supervise the initial lighting.
Space Heaters
Every winter, fires are started by space heaters. Electric space heaters can start fires in many different ways: by being plugged into outlets that are wired with insufficient wiring (causing resistance and heat), by the heaters being placed too close to flammable items, and by being tipped over.
To ensure that the wiring is safe, inspect the system to see that the wires are marine grade and of a sufficient gauge, properly connected to a circuit breaker or fuse, and that all connections are made with marine connectors and protected with heat-shrink tubing. Anything less will corrode and can significantly increase the risk of an electrical problem.
I purchased my boat from a lifelong boater who, as it turned out, had taken some shortcuts with the electrical wiring, and had wired the bilge pump with household wiring and wire nuts. Sure enough, all of the connections failed and the interior of the boat flooded. Don’t take anything for granted when it comes to a safe electrical system.
Some space heaters have safety mechanisms that are supposed to shut down the heater in the event that the heater is tipped over. I can tell you from experience that these safety mechanisms do not always work. The only safe way to use a portable space heater is to supervise it when operating.
My closest call with an electric space heater occurred when I was reading in my v-berth and the heater was down on the floor outside the cabin. A blanket had fallen off the berth and landed on the heater. I soon smelled the smoke, and the smoke detector went off immediately after that. Though a serious fire was prevented, some bad odors lingered for a while and that blanket had a bit of a burn mark.
There are viable alternatives to space heaters with ceramic or exposed heating elements. Oil-filled heaters are regarded as much safer, having no exposed heating element; they become quite warm, but not so hot as to risk igniting anything around them.
Be very aware of the risks associated with these heaters and take careful precautions. Smart people die every year from circumstances that could have been identified and rectified with a little effort.
Gasoline Fumes
Gasoline vapors are flammable. When gasoline inboard engines are used, the engine compartments often collect fumes that need to be flushed out prior to starting the engine. That’s why boats that use inboard gasoline engines have a bilge fan, which must be turned on for a designated length of time before the engine is started. Failing to do this creates a fire hazard.
Water, Floods, and Sinking
Despite the existence of millions of boaters, scuba divers, water sports participants, swimmers, and beachgoers (and I fall into all of the above categories), humans do not mix well with water. We require a breathing apparatus when under it, and can be swept away by an unexpected current. The water and the various creatures in it can hurt us in many ways. The sea is not our element.
Boats, when working as intended, do a wonderful job of protecting us by keeping us up and out of the water. Boats do this particularly well when the water is kept on the outside of the hull.
Yet water does come into the boat naturally. Many stuffing boxes are designed to leak a drop or two a minute (which will add up significantly over time). Water will gradually accumulate in the bilge from this and other sources and, when the water level rises to a certain point, the bilge pump turns on and takes that water overboard.
Boaters don’t like to see water accumulate inside their homes and are fanatical about locating its source when they see it. While some boats can actually float when flooded, most cannot. Even the boats that can float will sink much lower in the water, becoming inoperable and more susceptible to other dangerous marine conditions. The idea is to take steps to ensure that the boat is safe and dry and, in the event of a problem, have provisions on board to deal with it.
Bilge Pumps
The bilge pump sits in your bilge and switches on when the water rises to a certain level, draining the water overboard.
Keep this pump in working condition. It is not sufficient to know that the bilge pump works—you must periodically inspect the wiring and bilge for anything that could indicate an impending failure or otherwise block the water flow or drainage. Bilge pumps do fail and burn out over time. When the pump fails, you do not want to be in a situation where the water level can rise above the floorboards or to any unsafe level. Have a replacement on board.
An examination of the bilge typically turns up visible water, which should be well within safe limits. Be sure that your bilge pump float switch is set to a level that does not keep the bilge pump running, but does not allow the water level to get too high. It is recommended that you consider adding a second or even a third bilge pump, each slightly higher than the last for redundancy and added capacity. Also consider installing a high-water alarm in connection with the second pump level, so you know when both pumps are engaged, or to indicate the failure of the first pump.
Be absolutely certain that the bilge pump(s) is/are wired in such a method as to ensure that the pump(s) will work even when all of the electronic circuits have been shut off, as many boaters shut all of the power down when they leave the boat.
There might be occasions when either the float switch fails or you need to operate the pump manually. I highly recommend a bilge pump switch that has three settings: on, off, and auto. “Auto” allows the pump to
operate when the float switch is triggered, “off” disables the bilge pump, and “on” will override the float switch. This system has come in handy for me on many occasions and only failed me once, when I inadvertently hit the switch to the off position. Don’t do that.
A boat can flood for two reasons: the bilge pumps fail, or the water enters the boat too quickly for the bilge pump to keep up. A reliable backup (capable of operating under all conditions including power loss) is the incorporation of a manual bilge pump with a handle placed topside so that, in the unfortunate instance that there is too much water below or some other failure, the bilge can be cleared of water without your having to get wet. Also, if the bilge pump below cannot keep up with the influx of water, another crew member can operate the manual bilge pump in addition to the pump below to drain the boat more readily. Many new boats are now shipped with this as a standard safety accessory. I would have much appreciated this when, in the middle of winter, my boat flooded with frigid water.
Lastly, before talking about the various ways water can enter a boat, it is important to mention the final, and critical, safety precaution. Listen. If the bilge pump turns on often, water is entering too quickly. Find out where the water is coming from!
There are many areas for water to enter. Assuming that a boat’s hull is structurally sound, water can enter anywhere there is a through-hull, any hose or system connected to the through-hull, anywhere that a shaft passes through the hull (such as a propeller shaft and rudder shaft), or any leak in the fresh-water system. Water can also enter from the deck, ports, hatches, and companionway during wet and cruising conditions, but those are not the types of concerns we are talking about.
Through-hulls and Seacocks
Through-hulls are holes through the hull. Any through-hull below the waterline will flood a boat if water is allowed to enter in an unconstrained manner. Therefore, a leak in any system connected to a below-the-waterline through-hull will flood and sink the boat if unattended.
Through-hulls are necessary. Engines that use outside (raw) water to stay cool use a through-hull to bring in water from outside the boat, and they exhaust that water through a second through-hull just barely above the waterline. Most heads use raw water to flush, and those boats that are equipped with a macerator to remove waste, or even a direct-to-overboard toilet, will have another through-hull where the waste exits the boat. Air conditioning and refrigeration systems often use raw water, as well. Offshore vessels may have a salt-water faucet in the galley so dishes can be washed with raw water before being rinsed with fresh water, in order to preserve fresh-water supplies.
Any through-hull below the boat’s waterline must have a seacock, a valve that can be opened and closed with a simple 90-degree turn of the lever. Older boats were equipped with “gate” valves (valves that look like those on a gardening hose), which have a dial that must be turned many times around to open and close the valve. Not only do gate valves fail, but in an emergency you do not want to spend your time turning the dial around and around.
Your primary defense against flooding is the seacock. It is incumbent upon you that you know exactly where all of the seacocks are, so you can quickly access them in the event of a leak in any system. Liveaboards have a tendency to expand their possessions into every crevice, and seacocks tend to become more inaccessible. Be careful of this. Moreover, it is recommended that seacocks be closed for any system when not in use, as well as when there is no one aboard. This suggestion is often disregarded.
It is also recommended that seacocks be installed on through-hulls above the waterline, as well. The boats in the Pacific Northwest sank when above-waterline through-hulls without seacocks sank below the waterline as a result of the added weight of snow and ice. There was no way to stop the water from entering these boats.
When I was sailing, my boat commonly heeled over to the point that the through-hulls for the drain for either my galley sink (when heeled to port) or head sink (when heeled to starboard) would drop below the waterline. On a gentle heel, the sink would fill with sea water. On a hard heel, I have watched my sink overflow. Holding this position would have flooded the boat. I resolved this by adding seacocks to those through-hulls and closing them when under way.
If water is coming in, you must find it. If you don’t know where it is, shut every seacock first and test the systems one by one. When you find the system that is leaking, figure out where and why. If the leak is from a faulty hose, cut the hose and add a hose connector and clamps. If you don’t have the proper equipment, you may use a wooden bung to temporarily block the problem hose.
Water Hookups
“Water hookups” refer to what is often called “city water,” or a water connection that allows an external hose to be connected directly to the fresh-water system, bypassing the water tank. This has the benefit of allowing water to be used without filling a water tank.
There are two problems: One, the water is coming aboard at a very high pressure, more than most on-board fresh-water systems ever typically endure; and two, in freezing climates, both the external and internal hoses can freeze. We’ll deal with the issue of freezing hoses in a bit. The problem with the high-pressure flow of water, however, is a very real safety concern.
When a boat is connected to a water hookup and any part of the fresh-water system develops a leak, an unlimited quantity of water will flow unimpeded at high pressure into the boat, flooding her. Safety procedures should require that the city water be turned off when not in use and certainly when away from the boat. This can often be achieved with a simple 90-degree valve, like a seacock. Like closing other seacocks, boaters often neglect this task as they become more convinced that their systems are functional and reliable.
Another safety mechanism is a flow gate that opens when triggered by an internal system or closes when the water flows aboard too quickly. These are helpful systems, but can be very expensive and are typically not part of a standard installation.
The only safe protection against flooding from city water is not to use city water. Inevitably, one day you will forget to turn off the water when you leave the boat. While many liveaboards enjoy the benefits of city water, it is easy to read about the boats that have gone under from what would have otherwise been a small problem.
Stuffing Boxes
Different systems are employed to permit equipment that passes through the hull, such as propeller and rudder shafts, to function properly without leaking. Many boats use a stuffing box, or a system in which the shaft enters the boat through two nuts that tighten onto a mechanism through which the shaft is passed. This mechanism contains a “stuffing” to both allow the shaft to spin and prevent water from entering. Some stuffing boxes are designed to leak water at a drop or two per minute to maintain lubrication, and others are designed not to leak at all.
If your boat has a stuffing box that is designed to leak (some aren’t), be sure that the flow is at the recommended rate (e.g., perhaps one drop per 60 seconds). If your stuffing box is not designed to leak, make sure that it doesn’t.
For stuffing boxes that leak, as the stuffing gradually compresses, the water will flow more quickly and the stuffing box either needs to be tightened or the stuffing replaced. It doesn’t take long for a faster flow to have a material impact on how often the bilge pump will need to cycle on. If you can’t find any other location for the water accumulation, be sure to check these locations. Many young boaters do not even think to examine the stuffing boxes, or even know what they are, but it is important to be aware of every source of water.
Engine (Raw Water) System
Some engines require that raw (sea) water flow through the engine to cool it. This water runs into the boat past a seacock—typically into a strainer to filter out grass and things that can cause engine problems—runs into the engine, exits the engine, and passes out through a through-hull that is typically above the waterline.
It is important that you not only understand the flow of your engine but al
so know which hoses are carrying this water. If one of them breaks, you will sink unless you get that seacock closed. If the strainer lid is too loose, the water will continue to flow into the boat as well.
I once tried to clean my raw-water strainer without closing the seacock. The water flowed in so fast that it was extremely difficult for me to close the strainer to stop it. I closed the seacock and tightened the strainer lid. I learned a lot about water pressure that day.
Freezing Water
For those liveaboards in cold-weather climates, freezing temperatures can be not only uncomfortable, but also dangerous and highly destructive in the event that water freezes inside a hose or the engine, or the water outside the boat freezes. This danger is substantially increased if a burst hose is connected to an unlimited supply of water, such as external seawater through a through-hull or a city water hookup. In that case, if the seacock is not closed and the leak repaired, the boat will flood.
Damage can also be caused when internal hoses freeze and burst. The freshwater tank in my boat has a capacity of approximately 70 gallons and the water heater another 6 gallons. Pump that into the cabin floor and that’s one hell of a flood, even if it is not enough to endanger the boat.
Also, as mentioned previously, water in and around the engine can freeze, severely damaging the engine, engine block, and other key equipment.
Liveaboards in cold climates have to make some decisions about their engines and water systems during cold seasons. Hoses that run through areas of the boat that are not constantly heated are highly susceptible to freezing. Unless the engine needs to be used during freezing conditions, it is strongly suggested that the engine intake seacock be closed and water in and around the engine and hoses be evacuated and replaced with antifreeze.