THE LOOP — A tourist checking out the Willis Tower's glass "Ledge," which allows folks to walk into glass boxes to see the city from 1,340 feet above the ground, got a scare this week when the Ledge cracked beneath him, NBC Chicago reports.
Willis Tower spokesman Randy Stancik said the tourist was never in danger — but all four ledge boxes were closed for "routine inspection" Thursday afternoon.
In a statement Thursday, Skydeck officials said the boxes were "temporarily closed" for the inspection and that they "hope to reopen shortly." The Skydeck remains open while a protective coating is being replaced.
A worker at the Skydeck said the four boxes would be closed for the rest of the day.
Stancik said the top layer of the Ledge was purely cosmetic, and was designed that way so tourists wouldn't have to wear special booties or socks when stepping out onto it, "like you'll have to do at the Grand Canyon," Stancik said, referring to the Skywalk, a transparent horseshoe bridge in Arizona.
"[The top layer of the Ledge] is designed to crack when somebody drops something on it," Stancik said. "It's not structural. The top piece is protective."
Despite the scary appearance of cracked glass, Stancik said the Ledge was totally safe and the top layer was being replaced Thursday.
"It's perfectly fine, you can go on it now," he said. "The top piece did it's job. It's a scratch piece for all practical purposes."
Until it is replaced, there's a carpet over the broken glass.
"But nobody wants to go on it," he said.
A professional design blog describes the ledge being made of three 12 mm tempered layers of glass and a 6 mm layer of "fully tempered, heat-soaked glass on top that can be removed or replaced if it gets scratched, cracked or damaged."
The post says that the ledge is designed with redundancies so that just one layer of glass is strong enough to support the lookout.
At the Skydeck on Thursday, Steve Truman and his two kids, visiting from Tennessee, were on the first elevator to visit the attraction. The group noticed one of the four "Ledge" boxes roped off with carpet covering it and thought nothing of it.
"They didn't say anything... That's crazy," Truman said showing a picture of his two kids jumping on another Ledge.
Michael Shatter was visiting for Australia and was also turned away but heard about the shattered ledge as he was exiting. He wished he still had the opportunity to see the Ledge.
"I'd be a bit nervous, but these things happen," said Shatter, 40.
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