IfcEvent

Item	SPF	XML	Change	Description
IFC2x3 to IFC4
IfcEvent			ADDED

Semantic definitions at the entity

Entity definition

An IfcEvent is something that happens that triggers an action or response.

HISTORY New entity in IFC4

Use definitions

IfcEvent is used to capture information about particular things that happen or that may happen. Particularly used in work plans (or process maps) they identify e.g. a point at which a message containing information may be issued or at which a rule or constraint is invoked.

Attribute definitions

#	Attribute	Type	Cardinality	Description	G
8	PredefinedType	IfcEventTypeEnum	?	Identifies the predefined types of an event from which the type required may be set.	X
9	EventTriggerType	IfcEventTriggerTypeEnum	?	Identifies the predefined types of event trigger from which the type required may be set.	X
10	UserDefinedEventTriggerType	IfcLabel	?	A user defined event trigger type, the value of which is asserted when the value of an event trigger type is declared as USERDEFINED.	X
11	EventOccurenceTime	IfcEventTime	?	The date and/or time at which an event occurs.	X

Formal Propositions

Rule	Description
CorrectPredefinedType	Either the PredefinedType attribute is unset, or the inherited attribute ObjectType must be asserted when the value of PredefinedType is set to USERDEFINED.
CorrectTypeAssigned	Either the EventTriggerType attribute is unset, or the attribute UserDefinedEventTriggerType must be asserted when the value of EventTriggerType is set to USERDEFINED.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	G
IfcRoot
1	GlobalId	IfcGloballyUniqueId		Assignment of a globally unique identifier within the entire software world.	X
2	OwnerHistory	IfcOwnerHistory	?	Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object, NOTE only the last modification in stored - either as addition, deletion or modification. IFC4 CHANGE The attribute has been changed to be OPTIONAL.	X
3	Name	IfcLabel	?	Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule.	X
4	Description	IfcText	?	Optional description, provided for exchanging informative comments.	X
IfcObjectDefinition
	HasAssignments	IfcRelAssigns @RelatedObjects	S[0:?]	Reference to the relationship objects, that assign (by an association relationship) other subtypes of IfcObject to this object instance. Examples are the association to products, processes, controls, resources or groups.	X
	Nests	IfcRelNests @RelatedObjects	S[0:1]	References to the decomposition relationship being a nesting. It determines that this object definition is a part within an ordered whole/part decomposition relationship. An object occurrence or type can only be part of a single decomposition (to allow hierarchical strutures only). IFC4 CHANGE The inverse attribute datatype has been added and separated from Decomposes defined at IfcObjectDefinition.	X
	IsNestedBy	IfcRelNests @RelatingObject	S[0:?]	References to the decomposition relationship being a nesting. It determines that this object definition is the whole within an ordered whole/part decomposition relationship. An object or object type can be nested by several other objects (occurrences or types). IFC4 CHANGE The inverse attribute datatype has been added and separated from IsDecomposedBy defined at IfcObjectDefinition.	X
	HasContext	IfcRelDeclares @RelatedDefinitions	S[0:1]	References to the context providing context information such as project unit or representation context. It should only be asserted for the uppermost non-spatial object. IFC4 CHANGE The inverse attribute datatype has been added.	X
	IsDecomposedBy	IfcRelAggregates @RelatingObject	S[0:?]	References to the decomposition relationship being an aggregation. It determines that this object definition is whole within an unordered whole/part decomposition relationship. An object definitions can be aggregated by several other objects (occurrences or parts). IFC4 CHANGE The inverse attribute datatype has been changed from the supertype IfcRelDecomposes to subtype IfcRelAggregates.	X
	Decomposes	IfcRelAggregates @RelatedObjects	S[0:1]	References to the decomposition relationship being an aggregation. It determines that this object definition is a part within an unordered whole/part decomposition relationship. An object definitions can only be part of a single decomposition (to allow hierarchical strutures only). IFC4 CHANGE The inverse attribute datatype has been changed from the supertype IfcRelDecomposes to subtype IfcRelAggregates.	X
	HasAssociations	IfcRelAssociates @RelatedObjects	S[0:?]	Reference to the relationship objects, that associates external references or other resource definitions to the object.. Examples are the association to library, documentation or classification.	X
IfcObject
5	ObjectType	IfcLabel	?	The type denotes a particular type that indicates the object further. The use has to be established at the level of instantiable subtypes. In particular it holds the user defined type, if the enumeration of the attribute PredefinedType is set to USERDEFINED.	X
	IsDeclaredBy	IfcRelDefinesByObject @RelatedObjects	S[0:1]	Link to the relationship object pointing to the declaring object that provides the object definitions for this object occurrence. The declaring object has to be part of an object type decomposition. The associated IfcObject, or its subtypes, contains the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. IFC4 CHANGE New inverse relationship, change made with upward compatibility for file based exchange.	X
	Declares	IfcRelDefinesByObject @RelatingObject	S[0:?]	Link to the relationship object pointing to the reflected object(s) that receives the object definitions. The reflected object has to be part of an object occurrence decomposition. The associated IfcObject, or its subtypes, provides the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. IFC4 CHANGE New inverse relationship, change made with upward compatibility for file based exchange.	X
	IsTypedBy	IfcRelDefinesByType @RelatedObjects	S[0:1]	Set of relationships to the object type that provides the type definitions for this object occurrence. The then associated IfcTypeObject, or its subtypes, contains the specific information (or type, or style), that is common to all instances of IfcObject, or its subtypes, referring to the same type. IFC4 CHANGE New inverse relationship, the link to IfcRelDefinesByType had previously be included in the inverse relationship IfcRelDefines. Change made with upward compatibility for file based exchange.	X
	IsDefinedBy	IfcRelDefinesByProperties @RelatedObjects	S[0:?]	Set of relationships to property set definitions attached to this object. Those statically or dynamically defined properties contain alphanumeric information content that further defines the object. IFC4 CHANGE The data type has been changed from IfcRelDefines to IfcRelDefinesByProperties with upward compatibility for file based exchange.	X
IfcProcess
6	Identification	IfcIdentifier	?	An identifying designation given to a process or activity. It is the identifier at the occurrence level. IFC4 CHANGE Attribute promoted from subtypes.	X
7	LongDescription	IfcText	?	An extended description or narrative that may be provided. IFC4 CHANGE New attribute.	X
	IsPredecessorTo	IfcRelSequence @RelatingProcess	S[0:?]	Dependency between two activities, it refers to the subsequent activity for which this activity is the predecessor. The link between two activities can include a link type and a lag time.	X
	IsSuccessorFrom	IfcRelSequence @RelatedProcess	S[0:?]	Dependency between two activities, it refers to the previous activity for which this activity is the successor. The link between two activities can include a link type and a lag time.	X
	OperatesOn	IfcRelAssignsToProcess @RelatingProcess	S[0:?]	Set of relationships to other objects, e.g. products, processes, controls, resources or actors, that are operated on by the process.	X
IfcEvent
8	PredefinedType	IfcEventTypeEnum	?	Identifies the predefined types of an event from which the type required may be set.	X
9	EventTriggerType	IfcEventTriggerTypeEnum	?	Identifies the predefined types of event trigger from which the type required may be set.	X
10	UserDefinedEventTriggerType	IfcLabel	?	A user defined event trigger type, the value of which is asserted when the value of an event trigger type is declared as USERDEFINED.	X
11	EventOccurenceTime	IfcEventTime	?	The date and/or time at which an event occurs.	X

Definitions applying to General Usage

Instance diagram

Concept usage

Object Typing

The Object Typing concept template applies to this entity as shown in Table 10.

HasType	RelatingType
	IfcEventType

Table 10 — IfcEvent Object Typing

The IfcEvent defines the anticipated or actual occurrence of any event; common information about event types is handled by IfcEventType.

Property Sets

The Property Sets for Objects concept template applies to this entity as shown in Table 11.

PsetName

Properties

Pset_Risk

Template	PropertyName	Value
Single Value	NatureOfRisk	IfcLabel
Single Value	SubNatureOfRisk1	IfcLabel
Single Value	SubNatureOfRisk2	IfcLabel
Single Value	RiskCause	IfcText
Single Value	AffectsSurroundings	IfcBoolean
Enumerated Value	RiskType	IfcLabel
Enumerated Value	AssessmentOfRisk	IfcLabel
Enumerated Value	RiskConsequence	IfcLabel
Enumerated Value	RiskRating	IfcLabel
Enumerated Value	RiskOwner	IfcLabel

Table 11 — IfcEvent Property Sets for Objects

Nesting

The Object Nesting concept applies to this entity.

IfcEvent may be contained within an IfcTask using the IfcRelNests relationship. The event is considered active during the time period of the enclosing task (including any assigned IfcWorkCalendar); that is such event may be triggered within the task time period but not outside of it. As an IfcEvent is considered to be atomic, no use is anticipated for nesting processes inside the event.

Sequential Connectivity

The Sequential Connectivity concept applies to this entity.

The relationship IfcRelSequence is used to indicate control flow. An IfcEvent as a predecessor (IfcRelSequence.RelatingProcess) indicates that the succeeding process (typically IfcProcedure or IfcTask) is triggered in response to the event. An IfcEvent as a successor (IfcRelSequence.RelatedProcess) indicates that the completion of the preceeding process causes the event to be triggered. As events have zero duration, the IfcRelSequence.SequenceType attribute has no effect on an IfcEvent but still applies to the opposite end of the relationship if IfcTask is used.

Control Assignment

The Control Assignment concept applies to this entity.

An IfcEvent may be assigned to an IfcWorkCalendar to indicate times when such event is active using IfcRelAssignsToControl; otherwise the effective calendar is determined by the nearest IfcProcess ancestor with a calendar assigned.

Product Assignment

The Product Assignment concept applies to this entity.

For building operation scenarios, IfcEvent may be assigned to a product (IfcElement subtype) using IfcRelAssignsToProduct to indicate a specific product occurrence that sources the event.

EXAMPLE An IfcSensor for a motion sensor may have a "Motion Sensed" event. If the IfcEvent is defined by an IfcEventType and the IfcEventType is assigned to a product type (using IfcRelAssignsToProduct), then the IfcEvent must be assigned to one or more occurrences of the specified product type using IfcRelAssignsToProduct.

mvdXML Specification


<?xml version="1.0"?>

<ConceptRoot xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" uuid="9a2ab9d1-08ba-4ea8-a84d-58e09f2ac59b" name="IfcEvent" status="sample" applicableRootEntity="IfcEvent">

  <Applicability uuid="00000000-0000-0000-0000-000000000000" status="sample">

    <Template ref="ea5cc6ee-1aa1-4da3-baec-f274e3806538" />

    <TemplateRules operator="and" />

  </Applicability>

  <Concepts>

    <Concept uuid="3ca2a179-a68a-4b61-9c5e-485beb184787" name="Object Typing" status="sample" override="false">

      <Template ref="35a2e10e-20df-40f4-ab2f-dacf0a6744f4" />

      <TemplateRules operator="and">

        <TemplateRule Parameters="RelatingType[Type]='IfcEventType'" />

      </TemplateRules>

    </Concept>

    <Concept uuid="c6574ea2-9c5c-4854-8ea2-28112a690155" name="Property Sets" status="sample" override="false">

      <Template ref="f74255a6-0c0e-4f31-84ad-24981db62461" />

    </Concept>

    <Concept uuid="c203d56a-56d6-4896-be2c-c122fc6bcc8d" name="Nesting" status="sample" override="false">

      <Template ref="38ca8788-5e47-411c-8294-d56f9e9a5691" />

    </Concept>

    <Concept uuid="6ada702b-6fdf-4c06-a829-0d9db744aba3" name="Sequential Connectivity" status="sample" override="false">

      <Template ref="c9f11880-8cf6-47fe-abac-05c73b4041b1" />

    </Concept>

    <Concept uuid="6c60f112-7269-4de1-9336-ecc0e362158b" name="Control Assignment" status="sample" override="false">

      <Template ref="813e73fe-5641-4648-a680-8887cf4359f1" />

    </Concept>

    <Concept uuid="401817a4-1ed1-4cad-8dc1-f89855248de6" name="Product Assignment" status="sample" override="false">

      <Template ref="ec9cfb04-adfe-4868-8168-d78fe995a913" />

    </Concept>

  </Concepts>

</ConceptRoot>

Concept inheritance

#	Concept	Template	Model View
IfcRoot
	Identity	Software Identity	General Usage
	Revision Control	Revision Control	General Usage
IfcObjectDefinition
	Classification Association	Classification Association	General Usage
IfcObject
	Object User Identity	Object User Identity	General Usage
	Object Predefined Type	Object Predefined Type	General Usage
	Property Sets with Override	Property Sets with Override	General Usage
IfcEvent
	Object Typing	Object Typing	General Usage
	Property Sets	Property Sets for Objects	General Usage
	Nesting	Object Nesting	General Usage
	Sequential Connectivity	Sequential Connectivity	General Usage
	Control Assignment	Control Assignment	General Usage
	Product Assignment	Product Assignment	General Usage

Formal representations

XML Specification

 <xs:element name="IfcEvent" type="ifc:IfcEvent" substitutionGroup="ifc:IfcProcess" nillable="true"/>

 <xs:complexType name="IfcEvent">

  <xs:complexContent>

   <xs:extension base="ifc:IfcProcess">

    <xs:sequence>

     <xs:element name="EventOccurenceTime" type="ifc:IfcEventTime" nillable="true" minOccurs="0"/>

    </xs:sequence>

    <xs:attribute name="PredefinedType" type="ifc:IfcEventTypeEnum" use="optional"/>

    <xs:attribute name="EventTriggerType" type="ifc:IfcEventTriggerTypeEnum" use="optional"/>

    <xs:attribute name="UserDefinedEventTriggerType" type="ifc:IfcLabel" use="optional"/>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcEvent

 SUBTYPE OF (IfcProcess);

  PredefinedType : OPTIONAL IfcEventTypeEnum;

  EventTriggerType : OPTIONAL IfcEventTriggerTypeEnum;

  UserDefinedEventTriggerType : OPTIONAL IfcLabel;

  EventOccurenceTime : OPTIONAL IfcEventTime;

 WHERE

  CorrectPredefinedType : NOT(EXISTS(PredefinedType)) OR (PredefinedType <> IfcEventTypeEnum.USERDEFINED) OR ((PredefinedType = IfcEventTypeEnum.USERDEFINED) AND EXISTS(SELF\IfcObject.ObjectType));
  CorrectTypeAssigned : NOT(EXISTS(EventTriggerType)) OR (EventTriggerType <> IfcEventTriggerTypeEnum.USERDEFINED) OR ((EventTriggerType = IfcEventTriggerTypeEnum.USERDEFINED) AND EXISTS(UserDefinedEventTriggerType));
END_ENTITY;

 EXPRESS-G diagram

	Ereignis
	Event
	Evènement