What is ISO 19904-1- Floating offshore structures about?
ISO 19904-1 provides requirements and guidance for the structural design and/or assessment of floating offshore platforms used by the petroleum and natural gas industries to support the following functions:
- Production
- Storage and/or offloading
- Drilling and production
- Production, storage, and offloading
- Drilling, production, storage, and offloading
The following types of floating structure are explicitly considered within the context of ISO 19904-1:
- Ship-shaped structures and barges
- Semi-submersibles
- Spars
- Shallow-draught cylindrical structures
ISO 19904-1 is applicable to all possible life-cycle stages of the structures defined above, such as:
- Design, construction, and installation of new structures, including requirements for inspection, integrity management and future removal,
- Structural integrity management covering inspection and assessment of structures in-service, and
- Conversion of structures for different use (e.g., a tanker converted to a production platform) or reuse at various locations.
In addition to the structural types listed above, this document covers other floating platforms intended to perform the above functions, consisting of partially submerged buoyant hulls made up of any combination of plated and space frame components. These other structures can have a vast range of variability in geometry and structural forms (e.g., tension leg platforms) and, therefore, can be only partly covered by the requirements of this document. In other cases, specific requirements stated in ISO 19904-1 can be found not to apply to all or part of a structure under consideration.
ISO 19904-1 is applicable to steel floating structures. The principles documented herein are, however, considered to be applicable to structures fabricated in materials other than steel.
NOTE: ISO 19904-1 is not applicable to the structural systems of mobile offshore units (MOUs). These include, among others, the following:
- Floating structures intended primarily to perform drilling and/or well intervention operations (often referred to as MODUs), even when used for extended well test operations;
- Floating structures used for offshore construction operations (e.g., crane barges or pipelay barges), for temporary or permanent offshore living quarters (floatels), or for transport of equipment or products (e.g. transportation barges, cargo barges), for which structures reference is made to relevant recognized classification society (RCS) rules.
Who is ISO 19904-1- Floating offshore structures for?
ISO 19904-1- floating offshore structures is useful for:
- Petroleum and natural gas industry
- Floating offshore structure operating companies
- Disaster management companies
Why should you use ISO 19904-1- Floating offshore structures?
It is important to recognize that structural integrity is an overall concept comprising models for describing actions, structural analyses, design rules, safety elements, workmanship, quality control procedures and national requirements, all of which are mutually dependent. The modification of one aspect of design in isolation can disturb the balance of reliability inherent in the overall concept or structural system. The implications involved in modifications, therefore, need to be considered in relation to the overall reliability of all offshore structural systems.
ISO 19904-1 addresses the offshore industry’s demand for a coherent and consistent definition of methodologies to design, analyze and assess floating offshore structures of the class described in Clause 1. Further applicable requirements are found in national and international codes and standards, and RCS rules.
ISO 19904-1 provides wide latitude in the choice of structural configurations, materials, and techniques without hindering innovation.
What’s changed since the last update?
BS EN ISO 19904-1:2019 supersedes EN ISO 19904-1:2006. BS EN ISO 19904-1:2019 includes technical changes with respect to EN ISO 19904-1:2006. These include:
- Title has been modified by replacing 'monohulls' with 'ship-shaped' and adding 'shallow-draft cylindrical structures'
- List of normative references (Clause 2) has been expanded
- Some definitions have changed, and some added terms and definitions (Clause 3) have been added
- Subclause on planning requirements (5.3) has been expanded by addressing inspection and maintenance philosophy (5.3.5), documentation (5.3.6), extreme weather preparedness (5.3.7), and disconnect able floating platforms (5.3.8)
- Subclause on use for project application (5.4.2) has been expanded with a paragraph regarding documentation for disconnect able floating platforms

