Ships and off-shore plants have very long lifecycles. Design data of ships and off-shore plants are used as master data in the subsequent phases after the design phase. Therefore, it is an important issue how to convert native design data generated from commercial shipbuilding CAD systems into neutral data with the use of international industrial data standards. International standard-based exchange of ship outfitting and off-shore plant data needs the construction of a library for specifications data of equipment and materials and the provision of external referencing mechanism for retrieving data stored in the library. This paper proposes an approach to construct a specifications data library with the use of ISO 15926 process plants. This library is used for providing specifications data through external referencing when translating ship outfitting data from TRIBON system into ISO 10303 STEP AP 227-formed data.