PrefaceThis is the first edition of CAN/CSA-ISO 19901-1, Petroleum and natural gas industries - Specific requirements for offshore structures - Part 1: Metocean design and operating considerations, which is an adoption without modification of the identically titled ISO (International Organization for Standardization) Standard 19901-1 (first edition, 2005-11-15). At the time of publication, ISO 19901-1:2005 is available from ISO in English only. CSA will publish the French version when it becomes available from ISO.
ScopeThis part of ISO 19901 gives general requirements for the determination and use of meteorological and oceanographic (metocean) conditions for the design, construction and operation of offshore structures of all types used in the petroleum and natural gas industries.
The requirements are divided into two broad types:
a) those that relate to the determination of environmental conditions in general, together with the metocean parameters that are required to adequately describe them;
b) those that relate to the characterization and use of metocean parameters for the design, the construction activities or the operation of offshore structures.
The environmental conditions and metocean parameters discussed comprise
- extreme and abnormal values of metocean parameters that recur with given return periods that are considerably longer than the design service life of the structure,
- long-term distributions of metocean parameters, in the form of cumulative, conditional, marginal or joint statistics of metocean parameters, and
- normal environmental conditions that are expected to occur frequently during the design service life of the structure.
Metocean parameters are applicable to
- the determination of actions and action effects for the design of new structures,
- the determination of actions and action effects for the assessment of existing structures,
- the site-specific assessment of mobile offshore units,
- the determination of limiting environmental conditions, weather windows, actions and action effects for pre-service and post-service situations (i.e. fabrication, transportation and installation or decommissioning and removal of a structure), and
- the operation of the platform, where appropriate.
NOTE Specific metocean requirements for tension leg platforms are to be contained in ISO 19904-2[1], for site specific assessment of jack-ups in ISO 19905-1[2], for arctic structures in ISO 19906[3] and for topsides structures in ISO 19901-3[4].
