Digging holes in the sand can be a serious hazard for you and your family.
"Early Show" Consumer Correspondent Susan Koeppen said plenty of people dig holes in the sand, but they don't know their holes can quickly cave in and trap those inside.
That's what happened to 12-year-old Reno Ciotola, who was playing on the beach in Ocean City, Md., last summer. He was digging a tunnel in the sand when suddenly it collapsed, trapping him underneath.
His mother, Debbie Ciotola, told Koeppen, "It was like concrete. I couldn't pull him out."
Lifeguards were able to dig him free, but he was unconscious with no vital signs.
Debbie said, "He was blue and purple and he had no pulse -- he wasn't breathing. He was clinically dead."
After CPR was performed, Reno eventually came to.
Reno says he doesn't remember anything of the cave-in; he just remembers waking up in a doctor's office.
As it turns out, Reno's case is hardly an isolated incident. Koeppen said in the past month, there have been two cases of sand hole collapses on beaches in California.
Harvard researcher Bradley Maron told Koeppen these aren't necessarily freak accidents. He's been following sand hole collapses for years, and of the 72 he's tracked over the past decade, 60 percent have been fatal.
In Ocean City, Butch Arbin, chief lifeguard, says people are being warned about sand hole safety "every day, all day long."
Arbin has been patrolling the beaches of Ocean City for 38 years. He says most people have no idea sand holes can be so dangerous. "It seems like good fun, but they don't think of the possible consequences," he said.
Koeppen pointed out sand holes can be stable one minute -- but any vibration -- even someone walking by -- can cause them to collapse. And the sand, Arbin said, can weigh, literally, hundreds of pounds.
Koeppen decided to see just how it would feel to be buried in the sand. She was placed into a three-foot hole and buried up to her neck.
She said the sand felt like a ton of bricks and it was hard to breathe while covered.
"The more I move the tighter it's getting," she said. "I wouldn't want that to happen in real life."
As for Ciotola, he has fully recovered from his real-life brush with death and says his sand hole digging days are behind him.
Debbie Ciotola told Koeppen parents who let their kids dig holes in the sand need to know something they think is innocent and isn't going to hurt your child "can be potentially harmful and take your child's life from you right in front of your eyes."
Koeppen added on "The Early Show" Thursday, a good rule of thumb for digging holes in the sand is to not make it any deeper than the knees of the smallest person in the hole.
And if you see a sand hole collapse, the best way to rescue someone, she said, is to dig with fewer people.
She explained, "Too many people trying to dig the person out can be bad and cause more sand to collapse. So you need one person digging and the other people behind that person moving the sand back and away from the person in the hole."