Martin McMenemy, aged 52, of Grimsby, was working for O Turner Insulation on the construction of a food processing plant in Ratby Lane, Leicester, on April 12 2008.
Leicester Crown Court heard today that he was using the scissor lift to install wall and ceiling panels when he drove it into a shallow pit. McMenemy was thrown clear when when the machine overturned but died later in hospital of head injuries.
An investigation by the Health and Safety Executive (HSE) revealed that O Turner Insulation and main contractor Clegg Food Projects, of Nottingham, had failed to take simple precautions to cover the hole.
The court heard the incident could have been prevented if the hole been covered with a metal plate or cordoned off.
Speaking after the hearing, HSE inspector Stephen Farthing said: "This was an entirely preventable tragedy. A family has been left without a father because simple precautions were not taken to eliminate what was an obvious hazard.
"Both companies had a duty to plan, manage and monitor the work being carried out under their control, but failed in that duty."
McMenemy’s oldest son, Ashley, 33, worked with him as a thermal insulation engineer at O Turner Insulation but changed career after the accident.
"I lost interest in working as a thermal insulation engineer following the incident,” said Ashley McMenemy. “The work wasn't the same and I simply didn't enjoy it any more.
"I miss Dad and I am upset that if I ever have any children he will not get to see them. I often think of him, and all the things we haven't yet done. I miss getting to know him better."
O Turner Insulation pleaded guilty to breaching the Construction (Design and Management) Regulations 2007 and was fined £22,500 with £12,806 costs.
Clegg Food Projects admitted breaching the same regulations and was also fined £22,500 with £12,674 costs.