Developing Best Practices for Arctic Offshore Structures

In order to improve existing industry guidelines for the safe design of both fixed and floating structures in Arctic offshore regions, DNV is kicking off a new joint industry project. Several of the major oil and gas players have already committed themselves and a recommended practice for ice effects on offshore structures will now be developed.

The most important standard for Arctic offshore structures is ISO 19906 (Petroleum and natural gas industries -- Arctic offshore structures). This is intended to harmonize and update existing regional and national codes and to ensure that Arctic offshore structures provide an appropriate level of reliability with respect to personal safety, environmental protection and asset values.

"However, ISO 19906 is 'open-ended' in a number of its recommended design practices, and it does not contain specific requirements for mobile drilling units or FPSOs for cold regions," said Gus Cammaert, DNV's director for Arctic technology.

A Cohesive Industry Development

The DNV-led joint industry project will produce a recommend practice (RP) for ice effects on Arctic offshore structures. The document will identify and discuss issues that should preferably be addressed during the concept screening or FEED stage.

The main scope is to provide practical guidance on key issues related to the following topics:

  • Design methodology, particularly relating to safety philosophy and probabilistic design.
  • The characteristics, properties and conditions of sea ice and icebergs in selected areas.
  • Ice action scenarios and load prediction algorithms for fixed and floating structures.
  • A discussion of structure response for key design issues.
  • Case studies for fixed and floating structures.

In close dialogue with the ISO working group, the RP will be a companion document to the ISO19906 standard. The RP should be considered as a supplement to ISO19906’s informative provisions that provides practical design recommendations.

In order to ensure a unified approach and include the most relevant experience, representatives of operators, engineering and shipbuilding companies and research institutes are committing and contributing to the development.

Some of the major participants include StatoilHydro, Shell, Transocean, Daewoo Shipbuilding, Hyundai Heavy Industries, Aker Arctic and Olav Olsen. In total, in addition to four business units within DNV, a total of 15 organisations from eight countries (including the US, Russia and China) are represented. Additional sponsors are welcome.