Avoiding Fatal Fumes

December 28, 2017

Carbon monoxide detectors are essential for protecting you and your onboard guests.

You can’t smell it, see it or taste it, but it can make you super sick and even kill you. In fact, according to the U.S. Coast Guard, carbon monoxide (CO) poisoning ranks fifth in top five known causes of fatalities among boaters—and is the number one cause of illness and death by poisoning. To assure the safety of you and your passengers, Pantaenius America strongly recommends you install CO detectors aboard your yacht. Keep reading for expert tips on what to buy, along with steps you can take to prevent lethal fumes from coming aboard. But first, a quick synopsis of where the dangers lie.

Surprising Sources of CO Poisoning

The most prevalent source of CO is exhaust from gasoline engines and generators. But there are many other ways this lethal gas can invade your vessel. For starters, CO can creep into your living space from a boat that’s docked, beached or anchored alongside you. For example, if you are at anchor or in a mooring field, the boat upwind of you may be running a gasoline generator—either below deck or a portable air cooled Honda generator on deck—and those fumes could drift downwind to your yacht. 

Slow speeds or idling in the water can cause carbon monoxide gas to accumulate in the cabin, cockpit, bridge and aft deck—even in an open area. And a tailwind can increase accumulation. 

Backdrafting—aka the “station wagon effect”—can cause CO to build up inside the cabin, cockpit and bridge when operating the boat at a high bow angle, with improper or heavy loading or if there is an opening which draws in exhaust. This effect can also cause CO to accumulate inside the cabin, cockpit, aft deck and bridge when protective coverings are used, and the boat is underway. 

Heaters are another source for CO, as diesel-operated heaters blow hot air into the cabin, and if there is a leak in the exhaust maniford, the exhaust gas gets mixed with the hot air and will be blown into the cabin. Cooking ranges produce CO as well—typically in amounts that aren’t cause for concern. However, if these devices are incorrectly installed, poorly ventilated or even partially enclosed, CO can quickly build to dangerous levels.

How you dock your vessel matters, too. If your generator exhausts out the side of the boat hull and you dock that side to a bulkhead dock and run the generator, the fumes may linger between your hull and the bulkhead and enter your yacht’s living quarters.

Know the Warning Signs

It’s easy to confuse the effects of CO poisoning with seasickness, intoxication, or too much exposure to the sun. The most common symptoms are headache, nausea, vomiting, dizziness and lethargy. Once CO is inhaled and enters the bloodstream, it begins to replace the oxygen you need to stay alive. In a CO-rich environment, this can happen in a matter of minutes, but the effects of CO are cumulative and can also build up gradually in a person’s bloodstream for hours or even days before reaching critical levels.

Preventing CO Poisoning

Your best defense against this potentially fatal problem is to install CO detectors on board, following these guidelines:

  • Battery-powered or hardwired? CO detectors can be battery-powered (the 9-volt type) or hardwired to a vessel’s DC system. One advantage of battery-powered units is they can be installed almost anywhere without the need for wiring. But there are downsides to this type of CO detector. Like their land-based counterparts, battery-powered marine detectors “chirp” to warn users when their internal battery is low. Thus, if there are weeks or months you don’t use your yacht, the unit may chirp for weeks before dying, and no one will be around to hear it. Battery life can also be unpredictable—plus these types of detectors are easy to disable by removing the batteries.

    With a hardwired detector, you need never worry about replacing batteries. Just be sure to wire these directly to a battery with a fuse in line and no on/off switch that can accidentally be turned off.

  • Where to install them? Place CO detectors in all enclosed or semi-enclosed areas (including an enclosed fly bridge), where people socialize or sleep. As for installation location, these don’t go in the ceiling like smoke detectors. Follow manufacturer’s instructions, but as a rule of thumb, shoulder or eye level works best, since, unlike smoke, which is hot and rises, CO lingers. Also, avoid installation near a hatch or porthole where water could come in contract with the device.

  • Residential or marine? Your first impulse may be to purchase a residential-type detector, but marine units are designed to withstand the elements of the sea. Many also boast extra features—like the ability to shut down a generator whenever high CO is detected and multi-channel monitoring, which allows detectors to sniff for fumes in different cabins. In other words, when one detector’s alarm activates, all connected detectors will alarm to alert passengers in other locations to the presence of CO.

Other Ways to Avoid the Dangers of CO Poisoning

  • Don’t allow swimmers near exhaust ports or under the back deck or swim platform when the engine or generator is operating. On calm days, wait at least 15 minutes after the engine or generator has been shut off before entering these areas. NEVER enter an enclosed area under a swim platform where exhaust is vented—not even for a second. And remember that teak surfing, dragging and water skiing within 20 feet of a moving watercraft can be fatal.

  • Schedule regular engine and exhaust system maintenance inspections by experienced and trained technicians.

  • Keep forward-facing hatches open, even in inclement weather. This will allow fresh air circulation in living spaces.

  • When possible, run the yacht so that prevailing winds will dissipate exhaust.

  • Dock, beach or anchor at least 20 feet away from the nearest boat that is running a generator or engine.

  • Operate stoves, heaters and generators in well-ventilated areas.

  • Educate all on board about CO so they are aware of the early signs of poisoning.

  • Test the operation of each CO detector before every trip.

  • If your CO detector goes off, believe it! Move to fresh air immediately, and seek medical attention if necessary.

Information provided by Captains Chris and Alyse Caldwell, owners of Captain Chris Yacht Services, LLC, 772.205.1859; www.captainchrisyachtservices.com Both are USCG licensed 100 Ton Masters and Cruising Coaches who offer Personal Boat Training online or onboard your boat anywhere! The Caldwells also offer training videos. You can email them at chris@captainchrisyachtservices.com.