It’s summer, steaming and people are heading to lakes to go boating and cool off. In other words, it’s the season for carbon monoxide poisoning.

The exhaust from a boat engine and from on-board generator this weekend killed one man, and sickened others, in two separate incidents in the boiling hot Southwest.

On Saturday at Bear Lake in Randolph, Utah, a passenger on a boat became sick, according to the Associated Press. His boat mates called 911 for help, assuming that he had heat stroke.

The man’s friends, and EMTs, performed CPR on the 22-year-old, to no avail. He was pronounced dead at the scene, and the Medical Examiner said the cause of death was carbon monoxide poisoning, AP reported.

The boat was an older model without an outboard engine, according to AP, and authorities believe the victim was sitting near an exhaust pipe and inhaled the lethal fumes.

In the second incident, on Sunday morning about a dozen people who were boating on Lake Mead in Nevada became ill because of exposure to carbon monoxide, apparently from a generator on the vessel, AP reported.

Five people were airlifted to a Las Vegas hospital; four were transported by ambulance; and three were treated and released, according to AP.

A family in Eau Claire, Wis., was rescued from potentially fatal carbon monoxide poisoning Wednesday night, which came from a generator in their basement, according to WEAU-TV.–203517181.html?ref=181

The local fire department was called to a home on Reserve Street, where two children had already exited and were standing with their grandmother, WEAU reported.

The first responders had carbon monoxide meters that showed them there were high levels of the lethal gas present in the house, according to WEAU. The parents were inside the home, unresponsive. They were taken to a hospital for medical treatment.

The source of the carbon monoxide was a generator that the family had operating in its basement, WEAU said. The Eau Claire fire chief advised town residents that gas-powered generators need to be kept outside and far enough away from a residence that its fumes can’t be blown back into the building by any wind, WEAU reported.

The home did not have any carbon monoxide detectors, according to authorities.