The Bradford-based firm, whose services include digital and screen printing, was sentenced over the June 2014 incident last week.

Richard Perry, 43, fell 5.5 metres through a fragile roof light to the fabrications department below while working alongside a colleague covering roof lights with blackout vinyl at Whiteghyll Plastics’ premises. This was in an attempt to block out the sunlight to reduce the heat within the factory.

The company, which works for high-street retailers, was found to have failed to have adequately supervised Perry and the other employee, with a number of managers missing several opportunities to stop them from working on the roof.

The Health & Safety Executive (HSE) prosecuted Whitegyll Plastics over the incident. The firm pleaded guilty to breaching Section 2(1) of the Health and Safety at Work Act 1974 and was fined £120,000 with £37,655 costs by Bradford Crown Court.

HSE inspector Andrea Jones said: “Two employees were on the roof for some time with no precautions in place to prevent falling through fragile roof material or off the open edge of the roof.

“This accident would not have happened if these two employees had been appropriately supervised by management. Falls from height, particularly from roofs, is the highest cause of fatal accidents.”

Perry’s wife Samantha, who was pregnant with the couple’s second son when he died, said: “Not only did my boys lose their daddy but I lost my husband, my best friend and my soulmate.

“Nobody should die at work and leave behind a young family and wife. He had his whole life ahead of him.”

Whitegyll Plastics was unavailable for comment at the time of writing.