4.1.7.1.6 Clearance Geometry
Elements requiring surrounding space for clearance provide a 'Clearance' representation. The reason for clearance space may be due to ventilation, maintenance, or other purpose. Examples of such elements include boilers and chillers. Such representation may be used for interference checks, where the 'Clearance' representation must not intersect with the 'Body' representation of other objects, though may intersect with the 'Clearance' representation of other objects.
The representation identifier of the clearance representation is:
The following diagram shows the generic classes and relationships used when applying this concept.
In addition, concepts may have particular importance to common or standardised industry practices and scenarios. For these specific usage scenarios, the table below shows a recommended list of general usage patterns that users may adopt.
G
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcElement.htm'>IfcElement</a>
IfcElement
1. GlobalId
[1:1]
2. OwnerHistory
[0:1]
3. Name
[0:1]
4. Description
[0:1]
HasAssignments
[0:?]
Nests
[0:1]
IsNestedBy
[0:?]
HasContext
[0:1]
IsDecomposedBy
[0:?]
Decomposes
[0:1]
HasAssociations
[0:?]
5. ObjectType
[0:1]
IsDeclaredBy
[0:1]
Declares
[0:?]
IsTypedBy
[0:1]
IsDefinedBy
[0:?]
6. ObjectPlacement
[0:1]
7. Representation
[0:1]
ReferencedBy
[0:?]
PositionedRelativeTo
[0:?]
ReferencedInStructures
[0:?]
8. Tag
[0:1]
FillsVoids
[0:1]
ConnectedTo
[0:?]
IsInterferedByElements
[0:?]
InterferesElements
[0:?]
HasProjections
[0:?]
HasOpenings
[0:?]
IsConnectionRealization
[0:?]
ProvidesBoundaries
[0:?]
ConnectedFrom
[0:?]
ContainedInStructure
[0:1]
HasCoverings
[0:?]
HasSurfaceFeatures
[0:?]
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProductDefinitionShape.htm'>IfcProductDefinitionShape</a>
IfcProductDefinitionShape
1. Name
[0:1]
2. Description
[0:1]
3. Representations
[1:?]
ShapeOfProduct
[1:?]
HasShapeAspects
[0:?]
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcElement.htm'>IfcElement</a>:Representation1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProductDefinitionShape.htm'>IfcProductDefinitionShape</a>:IfcProductDefinitionShape0
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>
IfcShapeRepresentation
1. ContextOfItems
[1:1]
Identifier
2. RepresentationIdentifier
[0:1]
Type
3. RepresentationType
[0:1]
Items
4. Items
[1:?]
RepresentationMap
[0:1]
LayerAssignments
[0:?]
OfProductRepresentation
[0:?]
OfShapeAspect
[0:1]
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcProductDefinitionShape.htm'>IfcProductDefinitionShape</a>:Representations1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:IfcShapeRepresentation0
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcGeometricRepresentationContext.htm'>IfcGeometricRepresentationContext</a>
IfcGeometricRepresentationContext
1. ContextIdentifier
[0:1]
2. ContextType
[0:1]
RepresentationsInContext
[0:?]
3. CoordinateSpaceDimension
[1:1]
4. Precision
[0:1]
5. WorldCoordinateSystem
[1:1]
6. TrueNorth
[0:1]
HasSubContexts
[0:?]
HasCoordinateOperation
[0:1]
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:ContextOfItems1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcGeometricRepresentationContext.htm'>IfcGeometricRepresentationContext</a>:IfcGeometricRepresentationContext0
IfcLabel_0
IfcLabel
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:RepresentationIdentifier1->IfcLabel_0:IfcLabel0
IfcLabel_1
IfcLabel
<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcShapeRepresentation.htm'>IfcShapeRepresentation</a>:RepresentationType1->IfcLabel_1:IfcLabel0
constraint_0
=Clearance
IfcLabel_0->constraint_0
Figure 4.1.7.1.6.A
General UsageTable 4.1.7.1.6.B