EXPERTS at Arup are testing two glass panels that mysteriously shattered and fell off the Millennium Point building in Birmingham.
Temporary scaffolding and a canopy have also been erected across the entrance of the £114 million building in case any more glazing fails.
The centre was built by a Galliford Try and Christiani & Neilsen joint venture and was completed in September 2001.
A team from Galliford Try is liaising with Arup and the glazing subcontractor Baco Contracts of Hertfordshire, which installed the cladding under a £4.6 million subcontract.
Galliford Try managing director Chris Bond said: 'We, in conjunction with our client Millennium Point, are investigating two incidents of glass breakage.
'We attended the site on the following day to survey the damage.We are consulting our specialist subcontractors to get a better understanding of how and why the glass failed.
'We do not yet know the nature of the failure and it would be premature to speculate.'
But sources at the client believe the fault lies in the actual glass rather than its installation.
A spokesman said: 'The two shattered panels have been sent for analysis and it will be a while before we identify the problem. But we are pretty sure that is is not down to the way that it was fitted but with the glass itself.'
No one was hurt when the glass shattered because, despite being more than 1 sq m in size, it was safety glazing and broke into small pieces.
The spokesman said: 'The building is fully operational and the shattered panel was not glass in the sense of a window - it was a decorative panel backed by a solid wall.
'The canopy has been put up as a precaution but these were just two panels out of hundreds in the building.'
Millennium Point is the largest Millennium project outside London and contains an Imax cinema and the Think-Tank science exhibition.