Walking in the east side of William Oxley Thompson Memorial Library, students might notice something different once they reach the atrium. A wooden barrier now rests where a glass panel once was.

Library employees noticed the broken panel the night of Feb. 26, before closing, and notified library security. It is unclear to employees and students when exactly the glass broke. Some officials said the window broke before the library closed Friday, Feb. 25.

The panel, located on floor 3M, has now been removed and replaced with plywood for precautionary reasons.

Library officials still don’t know what caused the glass to break.

Lucas Hatmaker, a fifth-year in criminology and sociology, said he heard the panel break Friday night.

“I was here when it happened,” Hatmaker said. “I heard this loud thud coming from the area. I just looked up quickly and didn’t notice anything or think anything of it, you hear noises in here all the time.”

David Lee, an architect from Acock Associates and project manager for the Thompson library renovation, said he expects a small percentage of the glass from Novum Structures to break due to internal stress or a defect in the glass.

“It’s a low percentage, less than 1 percent,” Lee said. “It’s a result of some unpredictability in internal stress as a part of the glass making.”

If there is deemed to be a flaw in the glass, Ohio State is not liable for the replacement costs as it is factored into the warranty with Novum Structures, a contractor for high technology architectural structures with several worldwide locations and four U.S. headquarters. If it is found to be an external cause breaking the glass, however, OSU will be responsible for the costs involved in replacement.

An internal flaw seems to be an unlikely cause, said Brad Anderson, project manager at Anderson Aluminum Corporation, the Columbus-based company in charge of replacing the glass.

“In my 28 years, I’ve seen it maybe twice,” Anderson said. “It’s extremely rare that it happens on its own.”

His best estimation is that something being thrown at the glass from the atrium side caused the breakage. This is due to only the exterior side of the panel breaking and a clear impact point on the glass itself, Anderson said.

This particular panel contains two pieces of glass, one exterior and one interior, encased by plastic. Anderson said it is four times harder to break than normal glass.

OSU Police has not been notified about the breakage, although it is under investigation, said Duke Morgan, head of security for OSU’s libraries.

Morgan also said if a culprit is found, there is sure to be legal action.

Weekend supervisor Amy Yuncker said the cause could be anything from vandalism to a bird possibly crashing into the window as wildlife sometimes finds its way into the building.

“We were really just baffled by it but delighted that they ruled out the possibility of an architectural flaw,” Yuncker said.

Students said they were not overly concerned about the issue.

“It really surprised me how little people questioned,” Yuncker said.

This is the first problem Thompson library has seen with the 192 atrium glass panels since its reopening in August 2009, Lee said.

OSU gave Anderson Aluminum a $1,000 purchase order to remove the glass and temporarily replace it while a new window is manufactured. The exact cost of the new window and installation is not yet known, but Lee estimates a total cost of about $2,000 to $3,000.

Anderson said the library will be without its window for a bit longer. He expects the new pane from Novum Structures to be manufactured in eight to 12 weeks.