The project context includes the definition of the default units within the IFC data set. They are declared once for the context of the whole data set. Default units are those units that apply:
Default units are defined as either:
EXAMPLE Meter is an SI unit without prefix, milli meter is an SI unit with prefix, inch and foot are conversion based units to be declared with a converstion factor to the SI unit (here meter), heat flux density (W/m2) is a derived unit with the unit elements Power (W) and Area (m2), and Euro is a monetary unit.
Figure 3 illustrates an instance diagram.
Figure 3 — Project Units
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