# 8.17.3.9 IfcQuantityVolume

## 8.17.3.9.1 Semantic definition

IfcQuantityVolume is a physical quantity that defines a derived volume measure to provide an element's physical property. It is normally derived from the physical properties of the element under the specific measure rules given by a method of measurement.

## 8.17.3.9.5 Formal representation

ENTITY IfcQuantityVolume
SUBTYPE OF (IfcPhysicalSimpleQuantity);
VolumeValue : IfcVolumeMeasure;
Formula : OPTIONAL IfcLabel;
WHERE
WR21 : NOT(EXISTS(SELF\IfcPhysicalSimpleQuantity.Unit)) OR
(SELF\IfcPhysicalSimpleQuantity.Unit.UnitType = IfcUnitEnum.VOLUMEUNIT);
WR22 : VolumeValue >= 0.;
END_ENTITY;