During retrieval of a document, when a create task is generated, the adapter must select a symbol to be used by the task. The adapter uses the Catalog Index to quickly find a suitable symbol to be used. The Catalog Index lookup is based on the type properties. For example, when generating a create task for Equipment, the Equipment Class/Subclass/Type properties are used to perform the lookup. Before the Catalog Index lookup can take place, the incoming SmartPlant type values must be converted into Smart P&ID type values. This conversion of an SmartPlant schema enum value into a Smart P&ID enumerated value is performed by the EnumConversions object just like any other enumerated property value. It depends on the mapping of enumerated values found in the tool schema.