CHICAGO » Alejandro Garibay says he knows now he wasn’t in danger when the ledge he was sitting on high above downtown Chicago started to crack — but when he first heard what sounded like breaking ice, he thought he was going to die.

"All I knew is the glass is underneath me, there’s 103 floors going all the way down, and this glass is broken — and I’m thinking I’m going to say hello to the sidewalk in just a few seconds," Garibay, a 23-year-old bank employee from Stockton, California, said Thursday.

Officials at the Willis Tower, a popular tourist attraction that was once called the Sears Tower, said it was the protective coating covering the four glass bays known collectively as The Ledge that was breaking beneath Garibay, his brother and two cousins on Wednesday night. A statement from the building’s management said the coating, which occasionally cracks, does not affect the "structural integrity" of the ledge.

But officials at the Willis Tower — the second-tallest building in the United States, according to the Council on Tall Buildings and Urban Habitat — said the four ledges were temporarily closed for "routine inspection." The rest of the Skydeck remained open.

The glass bays, which opened in 2009, attract visitors in part because walking onto them allows the disconcerting feeling of stepping onto air. And Garibay said when the coating started to look like a busted windshield and he felt tiny bits of it on his palms, he and his relatives jumped back to avoid going "flying" through the air.

"Up until that second it was awesome," he said. He and his family had been there at night so they could see fireworks at the Navy Pier. He said they did not get a refund.