This is the first edition of CAN/CSA-ISO 19901-7, Petroleum and natural gas industries - Specific requirements for offshore structures - Part 7: Stationkeeping systems for floating offshore structures and mobile offshore units, which is an adoption without modification of the identically titled ISO (International Organization for Standardization) Standard 19901-7 (first edition, 2005-12-01). At the time of publication, ISO 19901-7:2005 is available from ISO in English only. CSA will publish the French version when it becomes available from ISO.Scope
This part of ISO 19901 specifies methodologies for
a) the design, analysis and evaluation of stationkeeping systems for floating structures used by the oil and gas industries to support
- drilling, well intervention and production,
- production and storage,
- drilling, well intervention, production and storage, and
b) the assessment of stationkeeping systems for site-specific applications of mobile offshore units (e.g. mobile offshore drilling units, construction units, and pipelay units).
Most stationkeeping systems used with the class of floating structures covered by
a) are termed permanent mooring systems, for which this part of ISO 19901 is applicable to all aspects of the life cycle and includes requirements relating to the manufacture of mooring components, as well as considerations for in-service inspections. Most stationkeeping systems used with mobile offshore units, the class covered by
b), are termed mobile mooring systems. Throughout this document, the term floating structure, sometimes shortened to structure, is used as a generic term to indicate any member of the two classes, a) and b).
This part of ISO 19901 is applicable to the following types of stationkeeping systems, which are either covered directly in this document or through reference to other guidelines:
- spread moorings (catenary, taut-line and semi-taut-line moorings);
- single point moorings, anchored by spread mooring arrangements;
- dynamic positioning systems;
- thruster-assisted moorings.
Descriptions of the characteristics and of typical components of these systems are given in Annex A.
The requirements of this part of ISO 19901 mainly address spread mooring systems and single point mooring systems with mooring lines composed of steel chain and wire rope. This document also provides guidance on the application of the methodology to synthetic fibre rope mooring systems, and includes additional requirements related to the unique properties of synthetic fibre ropes.