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This guide describes SNOMED CT Release Format 2 (RF2), to be used for official production releases of SNOMED CT. This format is not mandated for internal terminology development usage or as an interchange mechanism between terminology development systems. RF2 provides a format that is flexible, unambiguous and useful. It was designed to strengthen SNOMED CT by providing a simple and stable format that enables innovation through adaptations to cater for changing requirements1 .

The component release files are defined in the following sections:

Ref Notes
1 This specification was developed by harmonizing proposals reviewed by IHTSDO Enhanced Release Format Project Group, including:
  • Enhanced Release Format Specification (SNOMED International Proposed Specification , 21 June 2007);
  • Reference Set Specification (SNOMED International Proposed Specification , 31 July 2007);
  • Alternate Release Format (proposed by NEHTA and their Australian Affiliates).