Transcript for What parents need to know about summertime hidden dangers
Back now with a hidden danger parents need to know about. Children being overcome by carbon monoxide fumes when outside swimming. Here's erielle reshef. Reporter: Tonight, a warning from the parents of these little girls. A day of fun taking a terrifying turn because of a hidden danger you can't see or smell. She was lifeless and limp. And her eyes were rolling back in her head. Reporter: The two girls, poisoned by carbon monoxide leaking from the generator of a houseboat. Maybe a minute and a half or two minutes was all it took for them to be overcome. Reporter: The girls, rushed to the E.R. Since 2000, 140 have died from boat-related posening. A 2015 death prompting Minnesota lawmakers to pass the first legislation in the country requiring carbon monoxide detection on boats. They may feel light-headed, nauseous, as starting to pass out. Reporter: Experts say swim and play away from areas that vent exhaust. And watch children closely when they play on rear swim decks and platforms. The sisters are okay, but their ordeal is a reminder. It's pretty scary. Thankfully, they're going to be just fine. Reporter: Experts say, find a place with fresh air. If no improvement, don't wait to seek medical attention. Thank you. Still ahead, the Powerball
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