The Norwegian Petroleum Safety Authority said it will begin an investigation into a gas leak at Statoil’s Mongstad facility last month.
Around 600 people were called to muster at the site after concerns the suspected gas leak could catch fire.
The aim of the investigation will be to clarify the events and identify the triggering and underlying causes of the incident.
It comes after Statoil was called to a number of meetings with the safety body following a string of incident both onshore and offshore.