This document specifies requirements and provides recommendations applicable to fixed, floating and grounded concrete offshore structures for the petroleum and natural gas industries and for structures supporting nationally important power generation, transmission or distribution facility. This document specifically addresses: a) the design, construction, transportation and installation of new structures, including requirements for in-service inspection and possible removal of structures; b) the assessment of structures in service; c) the assessment of structures for reuse at other locations. This document is intended to cover the engineering processes needed for the major engineering disciplines to establish a facility for offshore operation.