On Labor Day weekend, a local family decided to take advantage of the good weather by boating on Utah Lake. The day was especially calm, but as a group of kids were towed very slowly behind the boat they began to feel sick. Finally, one of the children passed out, rolling off a wakeboard and into the water.

Eugene R. Worth, M.D., M.Ed. — Medical Director of Hyperbaric Medicine at Utah Valley Regional Medical Center in Provo — said the children were suffering from carbon monoxide poisoning. Due to the boat’s slow speed and the lack of wind, exhaust accumulated around the family and poisoned a total of five people.

“The father felt awful,” Worth said. “He thought he was doing everything right.”

The five victims of the unusual accident were treated in the UVRMC hyperbaric chamber, and Worth said they suffered no apparent long-term damage. But, he added, the episode illustrates the dangers associated with carbon monoxide — an invisible and odorless gas. Worse still, the dropping temperatures mean the risk of carbon monoxide poisoning is rising.

“There’s a definite season for carbon monoxide poisoning,” Worth said. “And it’s now.”

Worth said anything that burns fossil fuels creates carbon monoxide. Common household sources of the gas include furnaces, fireplaces, water heaters and gas stoves. As people turn on their furnaces for the first time in the season, Worth added that the potential for poisoning goes up.

“If the furnace hasn’t been properly serviced, they’re going to be pumping carbon monoxide into their house,” he said.

Worth also recommended that people have their appliances serviced, their chimneys and flues cleaned and pointed out that they shouldn’t use fuel-burning machinery in enclosed spaces.

According to Worth, carbon monoxide poisoning occurs when people are exposed to the gas. After entering the body, carbon monoxide decreases the amount of oxygen in the blood by binding tightly to hemoglobin in blood cells. The effects can be extremely dangerous.

“It can leave you with permanent brain damage,” Worth said, adding that it even has the potential to kill.

While only victims in the more severe cases will suffer such dramatic consequences, others report experiencing nausea, headaches, difficulty thinking, fatigue and a general feeling of sickness. Some describe the symptoms as “flu-like.” And an unaddressed mild case can quickly escalate into something more severe; Provo City Fire Marshal Lynn Schofield said that most of the people who have died in Provo fires were actually killed by carbon monoxide well before the flames got to them.

Schofield said that every home should have carbon monoxide detectors on every level.

“They sound similar to a smoke alarm,” he said, “but they’re down low because carbon monoxide tends to be lower down, on the ground. They usually have to be plugged in and aren’t battery operated.”

Worth agreed with Schofield’s recommendation, and added that carbon monoxide can become trapped in tight spaces. It consequently can linger in basements, porches and other areas around homes.

According to Schofield, residents who suspect they may have found — or been victim of — carbon monoxide should call 911 immediately. Fire officials will check homes, and help people identify the source of the problem. Firefighters also can notify natural gas companies if needed.

Worth added that victims should get out of the affected area immediately, but may still need specialized treatment. At UVRMC, Worth treats victims by placing them in a hyperbaric chamber. The chamber pumps pressurized air into a room, and can dramatically speed up the process of purging the gas from the body.

So far this season authorities at UVRMC have treated eight people for carbon monoxide poisoning. Worth said the number is an increase over previous years, given how recently people have begun turning on their furnaces. In a normal season authorities typically will treat 20 to 25 patients, he said.

Worth added that authorities are working hard to encourage people to have detectors and do the proper maintenance.

“Be sure that you’re being safe,” he said.