Carbon Monoxide Danger From Boats a Grim Surprise

The houseboat trip to Lake Powell went without a hitch last fall until Ken Kidder, 42, of Denver dived under the boat, the Notorious, to retrieve an anchor rope tangled in a propeller. He sank and drowned.

“He said, ‘Hey, there’s an air pocket under here,’ and that was the last anyone ever heard from him,” recalled Jim Gabriel, 59, Kidder’s father-in-law, who was aboard the boat. “Four men dove in to find him and I’m leaning over the back of that deck calling his name and calling his name and it’s like every feeling I had in my body just drained out of me and I went numb. You knew he was gone. It was just too long underwater.”

When Kidder’s body surfaced four days later, tests showed extremely high levels of carbon monoxide in his blood. Boat exhaust had claimed another life at the Colorado River lake.

As more and more people enjoy water sports, new studies show that many mysterious drownings are the result of carbon monoxide emissions from boat engines and generators.

Since 1990, 482 boat-related carbon monoxide poisonings have occurred in 26 states, including California. Ninety-four of those victims died and 77 lost consciousness, according to a study conducted over the past two years by the U.S. Centers for Disease Control and Prevention and the U.S. Department of the Interior. Investigators suspect that the actual number of deaths is much higher because drowning victims are not always tested for carbon monoxide.

Carbon monoxide is colorless, odorless and tasteless and persists in the air. Once in the bloodstream, it rapidly starves the body of oxygen. Early symptoms, including headache, fatigue, confusion, nausea and dizziness, are easily confused with heatstroke, seasickness or intoxication. At high levels, it can lead to coma or heart attack.

Like Kidder, other people have succumbed after having swum under houseboats into air cavities filled with carbon monoxide. Others have been gassed as they clung to a wooden platform behind a slow-moving boat in a popular activity called “teak surfing.”

Eleven-year-old Anthony Farr was doing just that before he disappeared in Folsom Lake near Sacramento in late May. An autopsy determined that he had been overcome by carbon monoxide before drowning. His family filed a lawsuit last month against the boat maker.

A 9-year-old girl died and another was sickened when they stood in 2 feet of water beside a cabin cruiser as they rinsed their hair in warm water mixed with exhaust that spilled from an idling boat at Lake Powell last year, according to the Centers for Disease Control and Prevention.

Many houseboats vent exhaust gas from on-board generators to a hollow spot under the rear patio deck near the engines. Gases get trapped there.

The deaths came as a surprise to investigators. Carbon monoxide typically kills people in such confined places as garages. Yet, the gas can be deadly outdoors, when, for example, it blows back over the rear of a boat or enters the rear window of a moving station wagon.

“These deaths are very hard to deal with. People have no clue this is happening. I was shocked at what we found on these boats. It’s a serious public health issue,” said Jane McCammon, director of the Rocky Mountain office for the National Institute for Occupational Safety and Health.

With the peak boating season at hand this summer, and a long Independence Day weekend ahead, officials have stepped up warnings to the public.

At Lake Powell, just north of the Grand Canyon, houseboat rental firms now routinely tell people of the danger of carbon monoxide.

The 186-mile-long lake is among the nation’s premier destinations for houseboats and water-skiers. About 500,000 boat trips occurred at the lake last year, according to the National Park Service.

In the last nine years, 164 people have been poisoned by carbon monoxide at Lake Powell and 13 of them have died, McCammon said.

In 1995, a 16-year-old girl died inside a pleasure boat at the lake after riding for 45 minutes in the back of the boat near the exhaust pipes. That same year, rescue personnel found a beached cabin cruiser with one man dead at the helm and three others unconscious inside. Their boat had run aground after they were overcome by fumes and passed out. In 2000, two young boys from Colorado died when, like Kidder, they swam under a houseboat, went into convulsions and drowned.

After that accident, Dr. Robert Baron, the medical director for Glen Canyon National Recreation Area, pushed for a scientific study of air pollution around houseboats.

“These people are dying on my watch. I want it to stop. It’s heart-wrenching,” Baron said last week. “We were all mystified about this. We were recognizing this for the first time anyplace.” What’s happening at Lake Powell, he said, “is just the tip of the iceberg.”

Many boaters have no idea that boat exhaust can be a serious hazard.

“It’s not something I ever thought about, but I’ll guess we’ll do what they say and take these precautions,” said Andy Rodriguez of Mission Viejo as he boarded a houseboat at Lake Powell last month with his brother and their families.

Carbon monoxide is a product of poor combustion in engines. When concentrations reach 1,200 parts per million of air, federal health and safety experts consider it an immediate threat to health. At 12,800 ppm, just a few breaths can kill in minutes.

But at the exhaust port of the Sea Ray cabin cruiser where the girl died while washing her hair, researchers found up to 41,600 ppm of carbon monoxide.

In Kidder’s case, federal investigators said tests showed that carbon monoxide concentrations beneath the 68-foot houseboat he dived under reached 88,200 ppm -- seven times the lethal dose.

McCammon said investigators at Lake Powell sometimes wear protective moon suits when they test for carbon monoxide levels. McCammon, a federal industrial hygienist who has studied carbon monoxide in the workplace for the past 12 years, said not even factory workers or firefighters encounter such high concentrations of the toxic gas.

“I’ve never seen concentrations like this. It’s like a car was before catalytic converters. These people had no clue this was happening,” McCammon said.

At Lake Havasu on the California-Arizona border, up to 40,000 people in boats converge on a busy weekend. They concentrate in narrow Bridgewater Channel under the London Bridge, which crosses the Colorado River. Tests by Arizona health officials on Memorial Day weekend showed boaters had five times more carbon monoxide in their blood than a smoker has and enough to cause serious illness. Police and rescue personnel rotate shifts to shorten their exposure to the polluted air.

“All the exhaust leaves a smoggy haze in the channel you can see. It’s oil smoke haze and carbon monoxide mixed in with it. During busy times, the emissions hang in the air and it looks like a smoggy freeway in Los Angeles,” said Charlie Cassens, spokesman for Lake Havasu City.

Unlike cars, boats lack stringent emissions controls, particularly for carbon monoxide, although officials of the U.S. Environmental Protection Agency say it plans to regulate carbon monoxide from boats sometime in the future. Regulations have been approved for generators, but typically do not apply to those used on houseboats, according to the EPA.

Also, boats spend much of the year idle, so engines are often poorly maintained and dirty once they get on the water. Lakes, rivers and shorelines are getting more crowded -- about 17 million boats and personal watercraft are in use nationwide, according to industry estimates.

And boats are getting bigger, especially houseboats. Some come equipped with freezers, refrigerators, microwaves, TVs and electric ranges, all of which require bigger generators to power.

Monita W. Fontaine, vice president of government relations for the National Marine Manufacturers Assn., said boat builders have begun posting warning labels and installing carbon monoxide detectors in vessels and are working with the government and the American Boat and Yacht Council to develop carbon monoxide standards for boat engines. She said that houseboat makers are changing exhaust systems and that some boat owners, though not all, are complying with a Coast Guard-ordered recall of certain houseboats. Meanwhile, the Coast Guard has issued advisories against “teak surfing” and swimming around houseboats.

Fontaine said safety efforts are proceeding. “It’s a serious concern.... It would be wonderful if we could engineer this problem away, but we’re not there yet,” she said.