The user would like to access notifications of a MachineryItem. Those notifications may include prognosis information, noteworthy or abnormal conditions.

That leads to the requirement:

• All notifications of a MachineryItem shall be easily accessible (see 18).

Note: The notifications mentioned here are not necessarily all OPC UA Events a MachineryItem may produce (e.g., for job management defined in OPC 40001-3 (see [7])), but general notifications of a MachineryItem that may, or may not be modelled by OPC UA Events.