The Milford Haven operators of one of the largest oil refineries in Europe have been fined £400,000 after an employee sustained serious injuries.
Valero Energy UK Ltd admitted breaching Section 2 of the Health and Safety at Work Act by failing to ensure a safe working environment.
Swansea Crown Court heard how worker David Thomas, now aged 55, fell from a walkway linked to an oil tanker at the Rhoscrowther refinery in March 2012.
Mr Thomas suffered fractures to both legs, as well as dislocating his left knee, and now can't work due to arthritis.
Rupert Lowe, prosecuting, said the accident was caused by the poor design of the access walkway, plus mechanical difficulties.
A maintenance company employed by Valero had reported various issues over the years, and at one stage warned of “a potentially fatal accident waiting to happen.”
Mr Lowe said the prosecution accepted that Valero had responded to some of the issues raised by the maintenance company, but not adequately.
A proper risk assessment had not been carried out, there had been insufficient training and instructions, previous incidents had not been investigated properly and some recommendations had not been acted upon.
Mark Watson, representing Valero, said the company had an excellent safety record and had inherited the walkway from the previous owners of the refinery.
In hindsight, he said, it was the design of the equipment that had led to the problems and another system was now under design.
Judge Peter Heywood said the breaches were serious, as were the injuries suffered by Mr Thomas.
He said: "Clearly, this piece of equipment had problems from its inception. There were significant design problems."
But he said Valero had failed to “focus” properly after a series of incidents and the “strident” warning from the maintenance firm had proved to be true.
As well as the fine, Valero must also pay £60,614 in prosecution costs, as well as their own defence costs.
Their representative said the money would be paid in full within 28 days.