ISO DIS 19901-1

Description / Abstract: This 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:

those that relate to the determination of environmental conditions in general, together with the metocean parameters that are required to adequately describe them;

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 are

extreme and abnor mal 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 ac tion 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 site-specific assessment of jack-ups are contained in ISO 19905-1, for arctic structures in ISO 19906 and for topsides structures in ISO 19901-3.