Building merchant Travis Perkins has been fined £2m after a customer was run over and killed at its Milton Keynes yard.
Mark Pointer from Leighton Buzzard, died after being crushed by a company vehicle at Travis Perkins in Old Wolverton in November 2012.
The company had earlier pleaded guilty at Amersham Crown Court to two Health and Safety offences, where Judge Justin Cole said it "was an accident waiting to happen".
Pointer was loading planks onto the roof rack of his Land Rover, when he fell backwards after one of the cargo straps snapped. He fell to the ground where he was run over by a vehicle operating in the yard and died from crushing injuries.
Martin Brown, environmental health team leader at Milton Keynes Council, said the company had "failed to ensure loading and unloading activities were undertaken in a safe manner in a safe area".
"Individuals falling whilst loading and unloading vehicles is a common risk.
"While the term 'health and safety' is often incorrectly associated with trivial matters, true health and safety breaches can have devastating consequences as they did on this occasion."
John Carter, chief executive of Travis Perkins told Builders Merchant Journal: "It is with deep regret that we acknowledge the conclusion of the court hearing regarding the tragic incident that occurred in 2012. Our thoughts continue to be with the family of Mr Pointer.
"Minimising the risks for everyone working in and visiting our challenging environment is my responsibility, and I take it very seriously. Safety will remain at the top of our agenda; we will continue to apply the lessons learnt from this terrible event with the aim of ensuring that an accident such as this never occurs again."