The 34-year-old maintenance technician was investigating a fault on a new tilt table with a colleague at the UK’s largest glass manufacturer Solaglas.
Production machine manufacturer Lisec (UK and Ireland) Ltd was prosecuted following the incident at Solaglas (Architectural) Ltd, in Bishop Auckland on September 12 2007.
The table was part of a glass cutting line manufactured and installed by Lisec at the Solaglas plant just four months earlier in May 2007.
A jury at Teesside Crown Court heard the injured man was on his hands and knees while trying to fix a fault and had activated the emergency stop.
Suspended above his right wrist was a large laminated glass sheet measuring six metres by three metres and weighing almost a tonne.
The worker had his right arm extended with a mirror in his hand so he could check the status of a sensor relating to the release of the glass onto the table.
But when a colleague moved past another sensor on the tilt table the glass sheet was released, falling onto the maintenance technician’s wrist and severing his hand.
Surgeons reattached his hand with partial success and he was off work for several months while recovering from his injuries.
An HSE investigation found that there were faults within the programme controlling the movement of the glass.
Although the incident happened to a Solaglas employee at their premises, it occurred due to a fault on a new glass cutting line which had been installed by Lisec.
Lisec was found guilty of safety breached following a month-long trial and was fined £100,000 and ordered to pay costs of £150,000.
After the case, HSE Inspector Martin Baillie said: “This horrific incident should never have happened. Once he had put the table into an emergency stop condition, it should not have been possible to release the glass.”