Ian Dixey, prosecuting, told Chichester Crown Court on Monday that B&Q had failed in its duty of care to customers and a paramedic who were injured by stock which fell from the top of shelving at the Lyons Farm superstore on June 5, 2004.

Stuart Lednor, 48, from Lancing, suffered head injuries, a broken thigh and a fractured ankle after being hit by a cascade of kitchen doors which fell 15ft from the top of a storage rack.

His partner, Julie Forrest, was struck on the head by falling flat-packed boxes as she went to help him. Another customer, Mark Greening, was also hit as he went to assist the stricken couple.

Paramedic David Wells attended 10 minutes later and was told by staff the scene was secure. But as he injected Mr Lednor with pain relief, he, too, was hit a when yet another box fell, injuring his shoulders and spine.

Mr Dixey told the court how Mr Wells continued to treat the wounded customers even after he himself had been hurt.

Judge William Wood commended Mr Wells' action, saying "Despite an injury, he did his best to safeguard himself and carried on caring for the more seriously injured."

Mr Dixey said B&Q, who admitted breaching section three of the Health and Safety Act 1974, had been convicted of a catalogue of health and safety violations dating back to 1996 across the country.

He said the company's extensive health and safety "systems" for preventing accidents were not enough.

He added: "One can have the best systems in the world, but if you do not employ competent employees, you suffer the consequences of that."

Nicholas Haggan QC, for B&Q, said the company had a chain of health and safety accountability running from basic store employees and management
up to the board of directors.

But, he added, "There was a failure by managerial and other supervisory staff to implement in a satisfactory manner the system the company had put in place to ensure proper and safe storage of stock at all of its stores."

Mr Haggan said B&Q "very much regretted" both the "tragic accident" itself and the fact people had been injured as a result.

He said overall responsibility for the accident lay with the "highly-paid" general store manager who failed to ensure the appropriate checks were completed.

In sentencing, Judge Wood described the events as "a freak accident" and said he was impressed by B&Q's attitude to safety issues and its own investigation into what occurred to cause the accident.

He ordered B&Q to pay £33,641.14 costs in addition to a £15,000 fine.