QRA techniques on dynamic positioning systems during drilling operations in the Arctic: With emphasis on the dynamic positioning operator

Abstract

With the Norwegian government moving the ice edge farther north than ever before, opening for new areas for petroleum exploration, it will need research on how these areas can affect oil and gas operations. A sensitive environment along with the harsh Arctic climate and remote distances means that severe accidents, like blowouts, will have serious impacts and make cleanup and rescue actions to challenging operations. Additionally, humans working under these conditions are prone to be affected with regards to their reliability, which means that human errors are more likely to occur. The use of dynamic positioning systems as position-keeping solutions on mobile offshore drilling units is becoming increasingly popular as it is quick and easy to change position, independent on seabed conditions and does not need handling of anchors. The dynamic positioning operation is managed by an operator who is responsible for keeping the vessel in position, in addition to being a barrier for safely shutting in the well and disconnecting the riser configuration from the BOP when position-keeping is not possible. Quantitative risk assessment techniques have been used in the offshore industry for decades. They are usually applied to operations and systems, but are also possible to utilize for analyzing humans and their contribution in a risk picture. Based on a set of precautions, a model for analyzing dynamic positioning systems during loss-of-position events in the Arctic, with the focus particularly on the dynamic positioning operator, is in this thesis developed. A fictional comparison between a dynamic positioning drilling operation influenced by Arctic conditions and a similar operation in an area not exposed to such conditions is also provided. The comparison will indicate to which extent the reliability of the dynamic positioning operator is decreased by influence of Arctic conditions, and the role this plays in the recovery phase of loss of position events. Hopefully the findings in this thesis can contribute to safer oil and gas operations in the Arctic.