A Corby firm has been fined £50,000 after 250 tonnes of wet concrete collapsed, leaving seven builders lucky to escape with their lives.
MPB Structures, of Crucible Road, admitted breaching the Health and Safety At Work Act by putting workers at risk.
The firm was also ordered to pay £35,362 costs.
Liverpool Crown Court was told the men fell more than 30ft on to wet concrete which contained bits of metal and wood at Liverpool John Moores University where the firm were building an atrium along with Wates Construction, of Leatherhead, Surrey.
Wates Construction, the principal contractor, also admitted breaching the act and was fined £50,000 and ordered to pay costs of £35,591.
The court heard that workers had been pumping concrete onto the third floor of the building for most of the day on September 19, 2007, when the supporting scaffolding holding up the concrete suddenly collapsed.
Workers suffered cement burns to their skin and eyes, as well as bone fractures.
A Health and Safety Executive investigation found both firms involved allowed the supporting scaffolding to be put up from a preliminary design which was clearly marked “for discussion and pricing purposes only”.
The drawing did not include all the information needed to erect the scaffolding correctly or safely. The scaffolding was not checked before the concrete was poured.
Health and Safety Executive inspector Susan Ritchie said: “This incident resulted in seven men falling about 10 metres on to wet concrete which contained various bits of metal and wood.
“The companies should have made sure they had an appropriate design they could use to build from, and that the structure was inspected before the concrete was poured.
“Instead, more than 250 tonnes of concrete was poured on to scaffolding incapable of taking such loads and the inevitable happened – it collapsed. These basic errors could easily have resulted in people dying.”
Nobody from MPB Structures was available to comment.