Checklist - Each Trip
- Educate all passengers about carbon monoxide poisoning.
- Make sure all exhaust clamps are in place and secure.
- Look for exhaust leaking from exhaust system components, indicated by rust and/or black streaking,
water leaks, or corroded or cracked fittings.
- Inspect rubber exhaust hoses for burned or cracked sections. All rubber hoses should be pliable and
free of kinks.
- Confirm that water flows from the exhaust outlet when the engines and generator are started.
- Listen for any change in exhaust sound that could indicate an exhaust component failure.
- Test the operation of each carbon monoxide detector by pressing the test button. Make sure the
battery is installed properly and is in good condition. Never remove the battery unless replacing
it with a new battery.
Checklist - Annually
- Replace exhaust hoses if any evidence of cracking, charring, or deterioration is found.
- Inspect each water pump impeller and the water pump housing, and replace if worn. Make sure
cooling systems are in proper working condition to prevent overheating and burn through the
exhaust system. (Refer to the engine and generator manuals for further information.)
- Inspect each of the metallic exhaust components for cracking, rusting, leaking, and loosening.
Pay particular attention to 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).
Safety Bulletin - Carbon Monoxide
AVOID THESE DEATH ZONES: Swimming near or under the back deck or swim platform. Carbon monoxide (CO) from
exhaust pipes of inboard engines and generators build up inside and outside the boat in areas near exhaust vents.
STAY AWAY from these exhaust vent areas and DO NOT swim in these areas when the motor
or generator is operating. On calm days, wait at least 15 minutes after the motor or generator has been shut off
before entering these areas. NEVER enter an enclosed area under a swim platform where exhaust is
vented, not even for a second; it only takes one or two breaths of the air in this "death chamber" for it to be
Blockage of exhaust outlets can cause carbon monoxide to accumulate in the cabin and cockpit area - even
when hatches, windows, portholes, and doors are closed.
Exhaust from another vessel that is docked, beached, or anchored alongside your boat can emit poisonous
carbon monoxide gas into the cabin and cockpit of your boat. Even with properly vented exhaust, your boat should
be a minimum of 20 feet from the nearest boat that is running a generator or engine.
Slow speeds or idling in the water can cause carbon monoxide gas to accumulate in the cabin, cockpit,
bridge, and aft deck, even in an open area. A tailwind (foce of wind entering from aft section of the
motorboat) can also increase acculmulation.
The "station wagon effect" or backdrafting can cause carbon monoxide to accumulate inside the cabin,
cockpit, and bridge when operating the boat at a high bow angle, with improper or heavy loading or if there
is an opening which draws in exhaust.
This effect can also cause carbon monoxide to accumulate inside the cabin, cockpit, aft deck, and bridge when
protective coverings are used and the boat is underway.
Teak surfing, dragging, and water skiing within 20 feet of a moving watercraft can be fatal.
is an opening which draws in exhaust.
Carbon Monoxide Facts
- Carbon monoxide is a potentially deadly gas produced any time a carbon-based fuel, such as gasoline,
propane, charcoal, or oil, burns. Sources on your boat include gasoline engines, generators, cooking ranges,
and space and water heaters. Cold or poorly tuned engines produce more carbon monoxide than warm, properly
- Carbon monoxide is colorless, odorless, and testeless and mixes evenly with the air. It enters your
bloodstream through the lungs and displaces the oxygen your body needs. Early symptoms of carbon monoxide
poisoning: irritated eyes, headache, nausea, weakness, or intoxication. Prolonged exposure to low
concentrations or very 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 carbon monoxide to migrate throughout the boat and into enclosed areas. New areas of concern
are the rear deck near the swim platform with the generator or engines running and teak surfing or
dragging behind a slow moving boat. /regular maintenance and proper boat operation can reduce the risk
of injury from carbon monoxide.
- All carbon monoxide poisonings are preventable!