Carbon Monoxide Campaign Launched
since the late 1990s when a rash of fatalities aboard houseboats
underscored the dangers of carbon monoxide poisoning, the marine
industry and the U.S. Coast Guard have been trying to figure out
how to minimize or eliminate infiltration of this dangerous exhaust
byproduct into the living spaces of recreational boats.
of carbon monoxide (CO) on boats include gasoline engines and generators,
cooking ranges, and space and water heaters. The tasteless, odorless,
colorless gas, produced any time a material containing carbon — such
as gasoline, wood, propane, coal or natural gas — is burned,
is called “the silent killer” for
good reason. Exposure to prolonged or high concentrations of CO
can result in death or serious injury because CO reacts with
hemoglobin and reduces blood’s oxygen-carrying capacity.
Symptoms mimic sea sickness.
more boatbuilders are installing carbon monoxide detectors
as standard equipment and boat owners are more aware of CO’s
the recent recall of certain sport cruisers, the firsthand report
of a boat owner and an ongoing study by the U.S. Coast Guard
all demonstrate that the risk of CO poisoning remains because the
problem defies a simple solution.
levels of CO at the helm stations and cockpits of 47 and 37 Excalibur
express cruisers sold by Wellcraft and Four Winns prompted their
Australian builder, The Riviera Group, to initiate a recall campaign
in late 2005.
Riviera’s report to the Coast Guard states that
no accidents or fatalities have occurred, federal law requires
that boatbuilders recall vessels when they contain defects
a substantial risk of personal injury.”
to a report by a Riviera spokesman,“ After the
design and building of our new M360and M400 Sport Cruisers, we tested
these products extensively for CO levels.
“What we found were levels of CO that exceeded the American
Boat & Yacht Council (ABYC) guidelines in the cockpit and helm
station areas. It is important to note that the ABYC guidelines seem
to say that ventilation is the only solution; we disagree and have
gone much further in developing other modifications to the boats
to reduce CO levels,” said Riviera.
in an aerodynamicist from the Australian GMH race car team to help
with a re-design of the boats’ hardtops to
eliminate backdrafting, also known as the “station wagon” effect.
Air moving over
or around a boat creates a low pressure or suction area around
the stern that can increase the CO level on the boat, according
to ABYC. “Under certain speed and operating conditions,
the low pressure area may form in other regions and permit carbon
monoxide to enter the hull through openings that are not on the back
of the boat.” These openings could include vents for air conditioning,
the head and galley, as well as port lights, hatches, doors and cockpit
and deck drains.
determined that the design of the exhaust bellows used on the MerCruiser
MX6.2 320HP, 496 MAG and 496 MAG HO engines with which the boats
were equipped was also contributing to carbon monoxide build-up. “Once the testing was complete we liaised
with Mercury in Stillwater, OK, who approved the fitting of enclosed
exhaust bellows,” according to Riviera.
The last component of the recall requires boat owners to take specific
measures to decrease risk.
Riviera says, “Ventilation of the cockpit is still paramount.” To
this end, a recalled boat will receive a decal warning of the need
to keep forward-facing port lights or windows open when vessels are
underway, particularly at speeds below 10 knots or when anchored,
docked or rafted with other vessels. Boat operators need to make
sure that the cockpit is well ventilated at all times when engines
and generators are running because CO can migrate from there into
enclosed cabin spaces.
owner of a 2004 Brunswick-built Meridian 381 Sedan Flybridge
reported to BoatU.S. that he’s been unable to use the boat
due to high concentrations of CO — in excess of 1,000 ppm,
high enough to cause permanent brain damage or death in less than
an hour — in the main cabin. The problem has been present since
the day he took delivery, regardless of whether the boat is in the
slip, underway or at anchor.
Although the “new boat smell” that
comes from plastic resins, veneers and upholstery can sometimes
trip CO detectors, the owner says that the detectors on his boat
sound only when the twin MerCruiser 8.1L engines and the generator
are running. Factory technicians have attempted without success
to locate the source of the fumes. The manufacturer continues to
test and make repairs. The owner is considering litigation since
his requests for a replacement boat have been denied.
for Meridian told BoatU.S. that the only issues they’ve
had with CO detectors occur when boat batteries drop below 12 volts.
He said they had problems with the “station wagon effect” on
the Meridian 580 model until the exhaust was routed underwater. He
also said that a design change for the 2006 391 (the 381 will be
discontinued) also routes the exhaust underwater.
to U.S. Coast Guard accident statistics, nearly 200 fatal CO poisonings
are known to have occurred on or near recreational boats over the
years. Since the symptoms from exposure to low levels are similar
to seasickness, the actual number of boaters who have been affected
by CO may be considerably higher than statistics indicate.
For the past
year, the Coast Guard and ABYC have been testing express cruisers
to “provide a better understanding of the CO exposures
that occur, to identify the most hazardous conditions and to begin
the process of identifying controls to prevent or reduce CO exposures,” says
Dan McCormick of the Coast Guard’s Office of Boating Safety.
The tests follow guidelines set up by the National Institute for
Occupational Safety and Health. NIOSH, which is part of the Centers
for Disease Control and became involved in the boating CO issue following
the houseboat deaths.
“A great deal of work has already been performed to evaluate
CO exposures and controls on houseboats, but less effort has been
given to understanding the extent of the CO hazard on other types
of recreational boats,” McCormick said.
monoxide accumulation is affected by a multitude of variables:
boat geometry, hatch, window and door openings, ventilation openings,
proximity to other structures (like docks and neighboring boats),
swim platforms, canvas enclosures, location of exhaust outlets,
vessel attitude, wind direction, boat speed and boat system maintenance.”
Ten different models of boats built by five different manufacturers
were evaluated while stationary and at various speeds from 5 to 25
mph. Each test boat was fitted out with multiple sensors so that
CO concentrations could be measured at various places on board and
with canopy enclosures set up in different configurations. Results
of the study are under review and should be published within a few
avoid CO dangers, the Coast Guard recommends:
- Install and maintain CO alarms inside your boat. Do not ignore
any alarm. Replace alarms as recommended by the alarm manufacturer.
[Note: At present, there are no known CO detectors designed for
permanent use in exterior areas.]
- Never sit, teak surf, or hang on the back deck or swim platform
while the engines and generators are running. Teak surfing is NEVER
a safe activity.
- 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 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.
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.
- Know where
and how CO may accumulate in and around your boat. The Coast
Guard Web site, www.uscgboating.org,
or call 800-368-5647 for a copy of the Coast Guard’s brochure, “Carbon Monoxide
Poisoning: What You Can’t See...”
- Get a Vessel Safety Check. A VSC is a free bow-to-stern safety
examination performed by local U.S. Coast Guard Auxiliary and U.S.
Power Squadron members. For more information, visit www.SafetySeal.net.
BoatU.S. Magazine, July 2006