Silent killer: Carbon monoxide and boats
Banner Health expert offers advice on how to protect yourself and your family from gas that can’t be smelt, seen or tasted
“It really is a silent killer. People will start feeling nauseous and think they’re sea sick when they actually have carbon monoxide poisoning.”


(July 19, 2018) – At the height of the summer fun-on-the-water season, a nationally recognized Banner Health expert on boating safety warns that a "silent killer," threatens people enjoying time at a lake or on boat.

Since 2000, unintentional carbon monoxide poisonings have accounted for more than 800 boating-related poisonings in 35 states; 140 of these poisonings resulted in death, according to the Centers for Disease Control and Prevention.

“It really is a silent killer,’’ says Robert Baron, MD, assistant clinical professor of Emergency Medicine at Banner – University Medical Center Phoenix. “People will start feeling nauseous and think they’re sea sick when they actually have carbon monoxide poisoning.”

Baron has studied the effects of carbon monoxide around lakes since the late 1980s, after seeing many deaths at Arizona’s Lake Powell that involved people who weren’t drunk or injured, people who simply fell into the water or lost consciousness while swimming. Baron was involved in the first of the CDC studies looking at the link between carbon-monoxide poisoning and houseboats.

Since then, Baron has worked to educate boaters as well as people who occasionally enjoy lakes to be careful of exposure to carbon monoxide.

Persons with carbon monoxide poisoning often overlook the symptoms (e.g., headache, nausea, dizziness, or confusion), and undetected exposure can be fatal.

The carbon monoxide from a boat can be more dangerous than the gas from cars, Baron says. 

Carbon-monoxide gas can build up in and around a boat in various ways, according to the United States Coast Guard:

  • Poorly ventilated canvas enclosures.
  • Exhaust gas inside enclosed places.
  • Blocked exhaust outlets.
  • Another boat's exhaust.
  • "Station wagon effect" or back drafting. 
  • Moving at slow speeds, idling or stopping. 

About Banner Health

Headquartered in Arizona, Banner Health is one of the largest nonprofit health care systems in the country. The system owns and operates 28 acute-care hospitals, Banner Health Network, Banner – University Medicine, academic and employed physician groups, long-term care centers, outpatient surgery centers and an array of other services; including Banner Urgent Care, family clinics, home care and hospice services, pharmacies and a nursing registry. Banner Health is in six states: Arizona, California, Colorado, Nebraska, Nevada and Wyoming. For more information, visit