Do not confuse Carbon Monoxide (CO) poisoning with seasickness, intoxication, or heat stress. If someone on board complains of fatigue, dizziness, irritated eyes, headache, nausea, or weakness, immediately move the person to fresh air, investigate the cause, take corrective action, and, if necessary, seek medical attention. Install a carbon monoxide detector in each accommodation space on your boat. Check detectors before each trip for proper function, and if the detector goes off, believe it!
Carbon monoxide is a potentially deadly gas produced any time a carbon-based fuel burns, e.g. gasoline, diesel, propane, charcoal, or oil. Sources include engines, generators, cooking ranges, space and water heaters. Cold or poorly tuned engines produce more carbon monoxide than warm, properly tuned engines. CO has no colour, odour or taste and mixes evenly with the air. It enters your bloodstream through the lungs and displaces the oxygen your body needs. Early symptoms of CO poisoning - fatigue, dizziness, headache, etc - are often confused with seasickness or intoxication.
Prolonged exposure to low concentrations, or short exposure to high concentrations, can lead to death. Each year, boaters are injured or killed by Carbon Monoxide. Most incidents occur on older boats and within the cabin or other enclosed areas. Exhaust leaks, the leading cause of death by carbon monoxide, can allow CO to migrate throughout the boat and into enclosed areas.
Areas of particular concern are the rear deck, cockpit and swim platform with the generator or engines running and teak surfing or dragging behind a slow-moving boat and/or moving slowly down wind so the CO can come in over the stern. Proper maintenance and boat operation can reduce the risk of injury or death from CO.
Click on the following link to see more info