Carbon Monoxide Poisoning While Boating: Causes and Symptoms

December 2, 2022

Carbon monoxide is a colourless, odourless, tasteless gas that cuts off the body’s oxygen supply when inhaled. It can be lethal for those exposed to high concentrations or for long periods of time. Carbon monoxide is a common hazard on vessels, so it’s important for boaters to know what to look out for and how to minimize the risk.

Symptoms of carbon monoxide poisoning

When inhaled, carbon monoxide gets into the blood stream and interferes with its ability to send oxygen to the tissues and organs. Without oxygen, the cells begin to die, and the organs eventually cease to function. Symptoms of carbon monoxide poisoning vary depending on the amount and length of exposure:

Mild: shortness of breath, nausea, headache
Moderate: severe headache, dizziness, confusion, fainting
Severe: increased heart rate, loss of consciousness, seizures

Severe cases can cause permanent brain damage or death within minutes. It’s important to note that symptoms of carbon monoxide poisoning that occur while boating can easily be mistaken for seasickness or intoxication. If anyone on your boat presents with these symptoms, it’s vital to get them to fresh air immediately.

What causes carbon monoxide poisoning while boating?

Carbon monoxide is produced by burning fuel. Common sources of CO on boats include the engine or motor, onboard generators, cooking ranges and space and water heaters. Generally speaking, the amount of carbon monoxide generated by these sources is not a problem, but the gas can accumulate easily if they are incorrectly installed, partially enclosed or placed in a poorly ventilated area.

When boats are stationary or moving slowly, they may be at risk of tail winds blowing exhaust from rear-venting appliances back onto the craft. When moored or anchored, exhaust from nearby boats can also present a danger.

How to minimize the risk of carbon monoxide poisoning on a boat

To minimize the risk of carbon monoxide poisoning, it’s important to make sure your boat is equipped with an efficient ventilation system to help prevent the gas from accumulating. You should also carry out boat maintenance regularly to ensure that all systems and appliances are in good working order. Here are a few other steps you can take to minimize the risk:

Make sure all fuel-burning devices are designed for marine use
Only idle the engine when in well-ventilated areas
Only heat and cook in the cabin when there is proper ventilation
Make sure areas with awnings are well-ventilated
Moor your boat at least 20 ft away from any boat running a generator or engine
Avoid swimming in areas where engines vent exhaust
Avoid the rear deck/platform for at least 15 minutes after shutting off the engine
Educate passengers about the dangers and symptoms of CO poisoning

Note that while carbon monoxide detectors are not required on recreational vessels in Canada, they are the best way to detect the gas and avoid CO poisoning. Keeping a detector on board is highly recommended.

Mitigate common boating risks with Drive a Boat Canada

The best way to mitigate boating hazards is to learn about them and be prepared. That’s why the Canadian government requires boaters to take a safety course and pass a boat license test in order to operate a motorized pleasure craft. Take Drive a Boat Canada’s Canadian boater safety course online to learn everything you need to know to keep yourself and others safe on the water!