scope:

NEN-EN-ISO 19901-1 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 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.