4 1 10 2004 (E) Petroleum and Natural Gas Industries - Specific Requirements for Offshore Structures - part 2 : Seismic Design Procedures and Criteria International Standard Primary Author mixed material ISO 2004 2002 (E) Petroleum and Natural Gas Industries - General Requirements for Offshore Structures International Standard Primary Author mixed material ISO 2002 2005-11-15 Petroleum and Natural Gas Industries - Specific Requirements for Offshore structures - Part 1: Metocean Design and Operating Considerations British Standars Institution Primary Author mixed material 2005 2006 (E) Petroleum and Natural Gas Industries- Floating Offshore Structures- Part 1: Monohulls, Semi-Submersibles and Spars International Standard Primary Author mixed material ISO 2006