Carbon Monoxide: The Invisible Killer

WHY IS IT SO DANGEROUS?

Carbon monoxide (CO) enters your bloodstream through the lungs, blocking the oxygen your body needs. Prolonged exposure to low concentrations or very quick exposure to high concentrations can kill you. Early symptoms of CO poisoning include irritated eyes, headache, nausea, weakness, and dizziness. These symptoms are often confused with seasickness or intoxication, so those affected may not receive the medical attention they need.

WHAT YOU NEED TO KNOW

• You cannot see, smell or taste CO
• The most common source of CO is a running engine
• Install and maintain a marine grade CO detector
• CO can make you sick in seconds and high concentrations of CO can kill
• CO symptoms are similar to and often confused with seasickness or alcohol intoxication
• Avoid closed-off, poorly ventilated areas of a boat when its engine is running
• Never ride or hang on a swim platform where gases accumulate when the engine is running
• If CO is suspected, open all windows, hatches, and ports to ventilate
• Move a person to fresh air if CO poisoning is suspected and seek medical attention

Where CO May Accumulate?

Carbon monoxide can accumulate anywhere in or around your boat.

Inadequately ventilated canvas enclosures

Exhaust gas trapped in enclosed places

Blocked exhaust outlets

Another vessel’s exhaust.
CO from the boat docked next to you can be just as deadly

“Station wagon effect” or back drafting

At slow speeds, while idling, or stopped. Be aware that CO can remain in or around your boat at dangerous levels even if your engine or the other boat’s engine is no longer running!

How to Protect Others & Yourself

You’re in command of your boating safety. Follow these simple steps to help keep carbon monoxide from poisoning you, your passengers, or those around others.

• Know where and how CO may accumulate in and around your boat.
• Maintain fresh air circulation throughout the boat at all times. Run exhaust blowers whenever the generator is operating.
• Know where your engine and generator exhaust outlets are located and keep everyone away from these areas.
• Never sit, teak surf, or hang on the back deck or swim platform while the engines are running. Teak surfing is NEVER a safe activity.
• Never enter areas under swim platforms where exhaust outlets are located unless the area has been properly ventilated.
• Although CO can be present without the smell of exhaust fumes, if you smell exhaust fumes, CO is also present. Take immediate action to dissipate these fumes.
• Treat symptoms of seasickness as possible CO poisoning. Get the person into fresh air immediately. Seek medical attention-unless you’re sure it’s not CO.
• Install and maintain CO alarms inside your boat. Do not ignore any alarm. Replace alarms as recommended by the alarm manufacturer.
• Follow the checklists provided on this website.
• Get a Vessel Safety Check. A VSC is a free bow-to-stern safety examination.

TRIP CHECKLIST FOR CARBON MONOXIDE

Each Time You Go On a Boat Trip

• Make sure you know where CO exhaust outlets are located on your vessel.
• Educate all passengers about the symptoms of CO poisoning and where CO may accumulate.
• When docked, or rafted with another boat, be aware of exhaust emissions from the other boat.
• Confirm that water flows from the exhaust outlet when the engines and generator are started.
• Listen for any change in exhaust sound, which could indicate an exhaust component failure.
• Test the operation of each CO alarm by pressing the test button.

Print and use these checklists, and do not operate your boat without doing the following:

Once a Month

• Make sure all exhaust clamps are in place and secure.
• Look for exhaust leaking from exhaust system components. Signs include rust and/or black streaking, water leaks, or corroded or cracked fittings.
• Inspect rubber exhaust hoses for burned, cracked, or deteriorated sections. All rubber hoses should be pliable and free of kinks.

Once a Year

Have a qualified marine technician:

• Replace exhaust hoses if cracking, charring, or deterioration is found.
• Ensure that your engines and generators are properly tuned, and well maintained.
• Inspect each water pump impeller and the water pump housing. Replace if worn. Make sure cooling systems are in working condition.
• Inspect all metallic exhaust components for cracking, rusting, leaking, or loosening. Make sure they check the cylinder head, exhaust manifold, water injection elbow, and the threaded adapter nipple between the manifold and the elbow.
• Clean, inspect, and confirm proper operation of the generator cooling water anti-siphon valve (if equipped).