Carbon Monoxide
Fuel safety and carbon monoxide awareness
Enclosed spaces containing fuel-burning engines or appliances should be well ventilated to avoid
carbon monoxide build-up. Fuel-burning engines or appliances should also be certified or
designed for marine use.
Carbon monoxide (CO) is an invisible, silent and deadly danger. It is a colourless, odourless gas
produced during the incomplete combustion of fossil fuels. It cuts off the oxygen supply to the
body, causing death in minutes. Symptoms of CO poisoning such as headaches, nausea, and
fatigue can be mistaken for seasickness or the flu because the deadly gas is undetectable.
Avoid CO poisoning:
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Do not idle your boat’s engine, heat its cabin or cook
unless doing so in well-ventilated areas.
Be especially careful in modified areas such as cabin
extensions and areas fitted with canvas tops.
Use a carbon monoxide detector designed for a vessel and
check the detector’s batteries before every trip.
Engines left idling in poorly ventilated areas create
dangerous concentrations of CO: a tail wind can easily
carry CO back on board.
CO can build up when: two vessels are tied to each other;
you are docked alongside a seawall; an improper load
distribution causes the bow to ride high; or when your
vessel is stationary and a fuel-burning appliance or engine
is running.
Swimmers take note: CO is not just a risk to boaters. You can be overcome by the gas in
minutes and drown. Areas of risk are underneath swim grids and between the pontoons of
houseboats.
Carbon Monoxide Hazards
It is very important that all boaters are made aware of the possible deadly
circumstances surrounding Carbon Monoxide poisoning.
Carbon Monoxide (CO) is a non flammable colourless, odourless, tasteless toxic gas produced
during the incomplete combustion of fuel - Natural Gas, Oil, Coal, Wood, Kerosene, etc.
Carbon Monoxide inhibits the blood capacity to carry oxygen. By replacing oxygen with carbon
monoxide in our blood, our bodies poison themselves by cutting off the needed oxygen to our
organs and cells, causing various amounts of damage - depending on exposure.
Low levels of carbon monoxide poisoning (10%) result in symptoms commonly mistaken for flu
and cold symptoms - shortness of breath or mild exertion, mild headaches and nausea. With
higher levels of poisoning (30%) the symptoms become more severe -dizziness, mental
confusion, severe headaches, nausea, fainting on mild exertion. At high levels of poisoning (50%
or more) there may be unconsciousness and death. Smokers and individuals with pathological
medical conditions are more susceptible to the effects of CO poisoning. Medical experts agree
that it is difficult to estimate the total number of carbon monoxide incidents because the
symptoms of carbon monoxide poisoning resemble so many other common ailments and these
go unreported as such.
Cooking, heating, or even leaving a motor on idle for too long, particularly where there are
enclosed or partially enclosed spaces, can result in a dangerous build-up of CO.
Particular attention should be paid to this issue when there are after market changes to a vessel
(cabin extensions, canvas tops fitted etc.) All boaters should use fuel-burning appliances only
under well-ventilated conditions. It is also important to be aware of exhaust gases and likely
places they may billow up and drift into an enclosed or partially enclosed space.
Carbon Monoxide Detectors (marine grade recommended) must be installed in accordance with
the manufacturer's instructions. CO Detectors should be mounted inside where recommended by
the manufacturer.
Enclosed spaces within the vessel are not the only places where the danger of CO poisoning
exists. Swimmers are urged to refrain from entering areas under swimming platforms mounted
on vessels or between the pontoons of houseboats or any other areas where air circulation may
be poor if any engine exhaust gases may have recently been released in these areas.
A person can be overcome by and succumb to CO inhalation in as little as a few breaths. This
danger is real and is known to have caused death within seconds. Carbon Monoxide being
colorless, tasteless and odorless, a sleeping person could not be aware that he or she is inhaling
it and may succumb in his or her sleep.
Note: The above statements are meant to be general in nature only and are not intended to
cover all possible situations. Anyone seeking further detailed information on Carbon Monoxide
poisoning should seek professional advice. Also, it should be noted that the symptoms described
may vary from person to person.
http://www.tc.gc.ca/eng/marinesafety/debs-obs-operation-carbon-menu-2034.htm