The incident is the third serious safety issue to affect the building in as many years. The 3 x 1m panel, which was located on the rear facade of the building is understood to have smashed due to a build up of chemical compounds in the glass.
According to the tower's managers the incident was a 'one off', but in February 2005 a piece of scaffolding fell from the roof of Birmingham's tallest tower, dropping 40 storeys to the ground, miraculously missing workers and cars below.
And in November of the same year, another incident took place where five pieces of aluminium cladding fell from the 122m-tall tower because of high winds, forcing the city centre to close.
Speaking to the Birmingham Post, project manager for the tower Russell Markow said: 'A single-glazed green coloured panel did shatter on the eighth floor of the building at around 6.30am on Sunday in the south-east corner of the tower,' he said.
'The glass panel shattered into small rounded fragments as all glass in the building is designed to do, so that if any panel is smashed it wouldn't pose a threat to the public.
'The incident was caused by nickel sulphide, which builds up over time and can cause glass to break. Our consultants say it is very unlikely this will happen again.'