Oil giant Shell has been repeatedly warned by the UK authorities about the poor state of its North Sea platforms.

The company’s dismal record undermines Shell’s public commitment to improve its performance after a fatal explosion on the Brent field in the North Sea in 2003 and raises further concerns about Britain’s ageing oil and gas equipment.

As recently as last November, the releveant authority, the Health and Safety Executive warned Shell it had “failed to implement a suitably resourced maintenance regime to achieve compliance with their maintenance strategy. This has led to an excessive backlog of maintenance activities for safety critical equipment”.

HSE records that Shell has been served with 42 notices since 1999, while BP, a company of similar size, has received 25. From 2002 to the end of last year among other North Sea operators, Total had been served with four notices, Chevron one and Amerada Hess two. Despite these high numbers, a Shell spokesman said at the weekend the company had been working hard and successfully to improve its track record. “Improving our performance is an important priority and we have set ourselves tough targets to do this,” he told the Guardian newspaper.