Man Says His Harness Broke on Water Slide That Killed 10-Year-Old Boy

Matt Hess said he had to hold on for dear life on the world's tallest water slide.

For advice on how to stay safe at water parks, see these tips shared by the International Association of Amusement Parks and Attractions and the Red Cross.

A year before 10-year-old Caleb Schwab died on a water slide at a Kansas City park, another visitor says his harness snapped off on the ride -- leaving him holding on for dear life.

Read: Lawmaker's Son, 10, Suffered 'Fatal Neck Injury' On World's Tallest Water Slide, Cops Reveal

Matt Hess says his harness broke as he visited the Schlitterbahn Water Park last year. A friend, Erika Conrad, took video of the terrifying moment.

“I heard Matt say ‘my harness is off’ and I’m like, ‘what?’ I was in shock," she told Inside Edition. “There are bars or handles you can hold on to... He said he just held on as tight as he could going down. My husband said that his harness was a little loose but he just held on as well.”

Conrad said the recent incident with little Caleb left her stunned.

“After something so tragic has happened it opened our minds up to, wow, that really could have turned out bad,” she said.

Caleb was killed Sunday. Police say he was one of three people in a raft as it dropped 168 feet. The two women in the raft with Caleb were unrelated to him and suffered minor facial injuries, police said.

Read: 3 Girls Injured In 40-Foot Fall From County Fair Ferris Wheel

One theory is that the little boy and the two women had a combined weight that was less than 400 pounds, which is the weight needed to keep the raft on the slide.

A witness said he overheard Caleb’s brother tell a water park employee: "I just saw my little brother die because of one of your attractions."

The water slide is called "Verruckt," which is German for insane. It stands at 168 feet tall, which is about the same height as Niagara Falls.

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