IfcRailing proper ownership

As we know, IfcStair can be represented in two ways

The IfcStair shall either be represented:

  • as a stair assembly entity that aggregates all parts (stair flight, landing, etc. with own representations),
    or
  • as a single stair entity without decomposition including all representation directly at the stair entity.

However it’s not possible to provide exact IfcRailing ownership data exporting IfcStair like assembly entity. Sometimes it’s important to assign IfcRailing to a particular IfcStairFlight/IfcRampFlight.

My question is, is it semantically correct to connect particular IfcStairFlight & IfcRailing using IfcRelNests without aggregating IfcRailing inside IfcStair assembly?