RM Berwick Steel Erection Services boss Richard Mark Berwick was fined £40,000 by Lincoln Crown Court and ordered to pay costs of £5,000.
He was also disqualified as a director for four years after a 23-year old worker from Kettering fell more than nine metres leaving him paralysed from the chest down.
The Health and Safety Executive prosecuted SDI Group UK Ltd of Main Street, Hardwick, Cambridge, Steel Construction Ltd of Bodmin Road, Coventry, and Berwick, the managing director of RM Berwick Steel Erection Services Ltd of Fairfield Road, Isham, Northamptonshire, after the incident on 8 February 2007 in Glossop, Derbyshire.
SDI Group were fined £80,000 and ordered to pay costs of £20,000 while Steel Construction was fined £50,000 and ordered to pay £22,000 costs.
The court heard that Wayne Simpson, now 26, from Kettering, Northamptonshire, was working at a construction site off Waterside, Hadfield in Glossop on the day of the incident. He was installing a new racking system when he fell more than nine metres to the concrete floor below.
The incident has left Simpson paralysed from the chest down and he is likely to use a wheelchair for the rest of his life.
HSE inspector Kevin Wilson said: “It is unacceptable that a young man should suffer such life-changing injuries while just trying to do his job. Mr Simpson has been left with a long-term debilitating condition because the two companies and Richard Berwick failed to ensure his health and safety.
“Employers must understand the importance of protecting their workforce. Mr Simpson should have been provided with an appropriate safe system of work to protect against falls. This could have included personal fall protection, such as a harness and work restraint lanyard fitted to a running line, and properly fitted safety nets.
“Companies should adequately plan for working at height and ensure fall protection and mitigation measures are in place so incidents like this do not happen.”