This explanation was requested by the PSA following its investigation of a gas leak on Gullfaks B in December 2010.
Published on 23 April, the inquiry report identified a number of deficiencies which had features in common with shortcomings noted during the follow-up of earlier incidents.
The PSA is worried about an apparent lack of effect for improvement processes established in Statoil after these and other incidents.
It accordingly asked Mr Michelsen, as the most senior executive responsible for the company’s operations on the NCS, to submit his account by 29 April.
The PSA will now review and assess the content of Mr Michelsen’s report, and will make no further comment until it has drawn its conclusions and decided how to follow up Statoil in the future.
See article on Statoil's web site (In Norwegian)