ISO 15926

The ISO15926 standard was started as a non-STEP standard in order to achieve results quicker by avoiding the complexity of translating the protocol from ARM to AIM level as is required by STEP. The standard initially comprised a data model and a reference data library, and now comprises the following parts:


Part 1: Overview and fundamental principles 
Part 2: Data model 
Part 3: Ontology for geometry and topology 
Part 4: Reference data 
Part 5: Procedures for registration and maintenance of reference data 
Part 6: Methodology for the development and validation of reference data 
Part 7: Implementation methods for the integration of distributed systems 

ISO15926-2 (Data model)
During the years 1990 -1997 the EPISTLE Core Model ('ECM') was developed by USPI-NL, PISTEP and POSC/Caesar. This was formalised as ISO 10303-221 ('AP221', see there). In 1996 POSC/Caesar proposed a new ISO standard, ISO 15926, that originally was based on a POSC data model, and would not require the mapping to the ISO 10303 "Integrated Resources". In the period 1997 - 2003 the POSC data model and the ECM were harmonised into the present version 4.5.1 of the ECM. In 2003 the model has been registered as the formal ISO 15926-2 standard.
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The modelling team consisted of:
- Mr. Matthew West, Shell IT International, UK
- Mr. Jan Sullivan, Information Logic, UK
- Mr. Hans Teijgeler, (then) Fluor Daniel, The Netherlands

ISO 15926-4 (Reference Data)
During the years 1990 -1997 the EPISTLE Reference Data Library STEPLib was developed by USPI-NL, PISTEP and POSC/Caesar. In 1996 POSC/Caesar developed the "PoscCaesar specification" derived from STEPLib with the aim to market it commercially. That was not successful and end 1998 a merger program was started to merge both libraries into the EPISTLE Reference Data Library (ERDL). This has not been a simple process as the reference data library contains many thousands of classes. Currently about 12000 classes have been merged. The library has now been registered as ISO TS 15926-4 (TS=Technical Specification).

Project leaders for the ISO15926-4 project are:
- Mr. Paul van Exel, Director Stichting USPI-NL
- Mr. Nils Sandsmark, Director POSC Caesar, Norway

The editors of the project are::
- Mr. Magne Valen Sendstad, POSC Caesar, Norway
- Mr. David Leal, Caesar Systems UK


Maintenance Agency
Currently the MA ( Maintenance Agancy) is setup that will operate under TC184/SC4. An ad hoc group develops the terms of reference for the maintenance operation. The main procedure to be followed has been approved by the ISO TMB and IEC SMB.

ISO15926-7 (Implementation)
Part 7 defines implementation methods required to use ISO 15926 to its full extent for data integration, sharing, exchange, and hand-over. This activity started in 1999, with the support from the EPISTLE Management Board. Initially the W3C (= World Wide Web Consortium) Recommendation for XML Schema was used, because that was the only schema available at that time. In 2004 the W3C Recommendation for OWL was published, and Part 7 was rewritten in OWL (= Ontology Web Language), because that language was considered more suitable for ISO 15926. The ballot for formal TS status closes June 6th, 2008.
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Project leader for the ISO15926-7 project is:
- Mr. Peter Paul Pruijn, Fluor, The Netherlands

The authors of the standard are: 
- Mr. Hans Teijgeler, (then) Fluor Daniel, The Netherlands (resigned as author on March 31, 2008)
- Mr. Onno Paap, Fluor, The Netherlands