This mobile drilling facility is operated by Valaris (formerly Rowan), and was working for Equinor on the Gudrun field in the Norwegian North Sea when the incident occurred.
During routine pressure testing of the BOP, the door of the blind shear ram came loose and was shot from its position. It landed four metres horizontally and 1.35 metres vertically from the BOP. The door is reported to weigh 1.9 tonnes.
The area around the BOP had been cordoned off in connection with the pressure testing, but the component which came loose is understood to have landed outside the cordon.
Nobody was injured in the incident.
The PSA takes a serious view of this occurrence. Work on the investigation will begin as soon as possible.
Its findings will be summarised in a report published on psa.no