You can use the namespaces of Expression Variables to differentiate between local variables and domain (business) object attributes. The namespaces are fixed and their names always start with a capital letter. Refer to the list of supported namespaces. Symbols for supported namespaces are always lowercase. If symbols have values that are Enumerated lists, the values may be all uppercase or all lowercase, depending on the symbol. Pay careful attention to case for these symbols.
Alarm.name
== "SomeAlarmName"
Alarm.state == "ESCALATED"
Location.location
== "71.0912121, -71,0812081"
supported attributes [None]
DataItem.EE425_DI.value
== 1.0
supported attributes [ value,
last, changed, unit, type, description, alias, age]
Device.serial == "PS121221"