enum IfcPermeableCoveringOperationEnum {
kIfcPermeableCoveringOperationEnum_GRILL,
kIfcPermeableCoveringOperationEnum_LOUVER,
kIfcPermeableCoveringOperationEnum_SCREEN,
kIfcPermeableCoveringOperationEnum_USERDEFINED,
kIfcPermeableCoveringOperationEnum_NOTDEFINED,
kIfcPermeableCoveringOperationEnum_unset
};