Carbon Monoxide poisoning is a serious problem amongst boaters
Carbon Monoxide poisoning is a serious problem amongst boaters
Carbon monoxide (CO) poisoning is a potentially deadly, yet preventable, problem amongst boaters

What Boaters Need to Know About Carbon Monoxide Poisoning

By DAN Boater

According to the U.S. Coast Guard's report on 2017 Recreational Boating Statistics, carbon monoxide poisoning ranks fifth in the top five known causes of death among boaters, and is the most common cause of illness and death by poisoning in boaters. An earlier joint study conducted by the U.S. National Park Service, the National Institute for Occupational Safety and Health, and the U.S. Coast Guard on carbon monoxide dangers associated with boating (particularly houseboats) revealed that more than 800 people have been poisoned by boating-related carbon monoxide in the last 15 years, with over 140 of these poisonings resulting in fatalities.

Carbon monoxide (CO) is one of the most dangerous poisons because often boaters don't realize it's present until it's too late. It's important to educate yourself about the dangers of carbon monoxide poisoning so that you can protect yourself and your fellow boaters.

Sources of Carbon Monoxide on Boats

Carbon monoxide is a poisonous gas that you can't see, smell or taste. It's produced when carbon-based fuels, such as gasoline and propane, are burned. Potential boating-related sources include engines, generators, space and water heaters, and cooking ranges.

Normally, the amount of carbon monoxide these sources produce isn't a cause for concern. However, if they're incorrectly installed, poorly ventilated or even partially enclosed, carbon monoxide can quickly build to dangerous levels.

When there's too much carbon monoxide in the air, it can enter your bloodstream through your lungs. Once in your bloodstream, it replaces the oxygen you need to stay alive. The resulting lack of oxygen can cause organ damage and death.

8 Risk Factors for Carbon Monoxide Poisoning

5 Ways to Prevent Carbon Monoxide Poisoning on Boats [infographic]

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You and your passengers are at increased risk for carbon monoxide poisoning if you:

  1. Own or operated a boat fitted with a rear vented exhaust system: This type of venting can cause carbon monoxide to build up above the water near the rear deck and swim platform.
  2. Regularly travel at slow speeds or idle in the water: This can cause carbon monoxide to build up in your cabin, bridge, cockpit, aft deck and open areas.
  3. Operate your boat at a high bow angle, overload or improperly load your boat, or own a boat with an opening that draws in exhaust fumes: This can put you at risk for back drafting, which can cause carbon monoxide to build up in your cabin, cockpit and bridge.
  4. Fail to maintain your boat properly: Blocked ventilation louvers and exhaust outlets can cause carbon monoxide to accumulate in your cabin and cockpit.
  5. Ski, "tube", wakeboard or surf within 20 feet of the boat while it's moving.
  6. Sit or swim near/under the rear deck or platform while the engine or generator is on. Safety experts recommend avoiding this area for at least 15 minutes after the engine is shut off.
  7. Dock, anchor or raft within 20 feet of other boats that have engines or generators running.
  8. Ignore routine CO detector maintenance.

9 Signs and Symptoms of Carbon Monoxide Poisoning

Carbon monoxide poisoning can occur suddenly or gradually, so it's important to be alert to the signs and symptoms and to call for emergency medical assistance if you notice any of them. Common signs and symptoms include:

  1. Headache
  2. Dizziness
  3. Blurred vision
  4. Confusion
  5. Weakness
  6. Nausea
  7. Vomiting
  8. Chest pain
  9. Difficulty breathing

The symptoms of carbon monoxide poisoning can increase in severity with prolonged exposure to carbon monoxide. Prolonged or high exposure to carbon monoxide can cause increased heart rate, loss of consciousness and seizures. If you're asleep or intoxicated, you may not notice the symptoms of carbon monoxide poisoning as they develop, putting you at risk for irreversible brain damage or death.

Some of the early symptoms of carbon monoxide can be similar to those of sea sickness, heat stress or intoxication. If you or a fellow boater experiences any of these symptoms, seek fresh air immediately. Once out in the open air, consider the cause of your symptoms and take appropriate action.

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Treating Carbon Monoxide Poisoning

If you suspect you or a fellow boater may be suffering from carbon monoxide poisoning:

  1. Seek fresh air immediately. If you can, shut off all potential sources of carbon monoxide and open the doors, windows and awnings on your way out.
  2. Call DAN Boater's 24/7 Emergency Medical Hotline right away. Be sure to inform our medics that you may be experiencing carbon monoxide poisoning. The medics may make an immediate recommendation, such as starting CPR, or they may begin making arrangements for transportation to, and treatment at, an appropriate medical facility.
  3. If the affected person is not breathing, begin CPR and continue until he or she starts breathing or emergency services personnel arrives. If there is no one to assist you, perform CPR for a minute before you call the Emergency Hotline.
  4. Follow up at a medical facility, if needed. Oxygen therapy treatment may be required depending on the severity of the exposure.

Carbon monoxide poisoning can pose a serious health risk for boaters. Depending on the circumstances, it may be necessary to perform on-site CPR and/or undergo emergency treatment at the closest medical facility. By taking steps to detect and treat carbon monoxide poisoning early, you can help to save your life or the lives of your passengers or fellow boaters.


It is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional medical or dental advice, diagnosis or treatment and should not be relied on to make decisions about your health. Never ignore professional medical or dental advice in seeking treatment because of something you have read on the DAN Boater website. If you think you may have a medical emergency, immediately call your doctor, dial 911, or contact emergency services nearest you.