prEN ISO 12006-2

SLOVENSKI STANDARD
01-februar-2025
Nadomešča:
SIST EN ISO 12006-2:2020
Gradnja objektov - Organizacija informacij v gradbeništvu - 2. del: Okviri za
klasifikacijo (ISO/DIS 12006-2:2024)
Building construction - Organization of information about construction works - Part 2:
Framework for classification and breakdown structures (ISO/DIS 12006-2:2024)
Hochbau - Organisation des Austausches von Informationen über die Durchführung von
Hoch- und Tiefbauten - Teil 2: Strukturen für die Klassifizierung und die Gliederung
(ISO/DIS 12006-2:2024)
Construction immobilière - Organisation de l'information des travaux de construction -
Partie 2: Cadre pour les structures de classification et les arborescences(ISO/DIS 12006
-2:2024)
Ta slovenski standard je istoveten z: prEN ISO 12006-2
ICS:
35.240.67 Uporabniške rešitve IT v IT applications in building
gradbeništvu and construction industry
91.010.01 Gradbeništvo na splošno Construction industry in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 12006-2
ISO/TC 59/SC 13
Building construction —
Secretariat: SN
Organization of information about
Voting begins on:
construction works —
2024-12-10
Part 2:
Voting terminates on:
2025-03-04
Framework for classification and
breakdown structures
ICS: 91.010.01
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
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Reference number
ISO/DIS 12006-2:2024(en)
DRAFT
ISO/DIS 12006-2:2024(en)
International
Standard
ISO/DIS 12006-2
ISO/TC 59/SC 13
Building construction —
Secretariat: SN
Organization of information about
Voting begins on:
construction works —
Part 2:
Voting terminates on:
Framework for classification and
breakdown structures
ICS: 91.010.01
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2024
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
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Published in Switzerland Reference number
ISO/DIS 12006-2:2024(en)
ii
ISO/DIS 12006-2:2024(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Structures .2
3.2 Objects .2
3.3 Asset related .3
3.4 Process .5
3.5 Resource .6
3.6 Supporting aspects .6
4 Principles for structuring information for the built environment . 7
4.1 Concept model .7
4.2 Information structures .8
4.3 Breakdown structures .9
4.4 Classification structures .9
4.5 Characteristics.10
4.5.1 Properties .10
4.5.2 Uncertainty .10
4.5.3 Information purposes .10
4.6 Partial breakdown structures .11
5 Implementation . .11
5.1 Structure development .11
5.2 Options for sub-tables . 12
5.2.1 Space classification . 12
5.2.2 Component classification . 12
5.2.3 Task classification . 12
5.2.4 Actor classification . 12
5.3 Short code . 12
5.4 Descriptive phrase . 12
5.5 Maintenance . . 13
5.6 Conversion . 13
5.7 Uses of information structures . 13
5.8 Combining information structures . 13
5.9 Use within applications and databases .14
5.10 Other classification tables .14
Annex A (informative) Classification table examples .15
Annex B (informative) Example breakdown and classification structures .27
Bibliography .34

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ISO/DIS 12006-2:2024(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent
rights identified during the development of the document will be in the Introduction and/or on the ISO list of
patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,
as well as information about ISO's adherence to the WTO principles in the Technical Barriers to Trade (TBT),
see the following URL: Foreword — Supplementary information.
The committee responsible for this document is ISO/TC 59, Buildings and civil engineering works,
Subcommittee SC 13, Organization of information about construction works.
This third edition cancels and replaces the second edition (ISO 12006-2:2015), which has been technically
revised.
ISO 12006 consists of the following parts, under the general title Building construction — Organization of
information about construction works:
— Part 2: Framework for classification
— Part 3: Framework for object-oriented information
Annexes A and B of this document are for information only.

iv
ISO/DIS 12006-2:2024(en)
Introduction
0.1  Background
This part of ISO 12006 was first produced when there was little international standardization of classification
systems for the built environment. Now, IEC/ISO 81346 and several national classification systems have
been developed, for example, in North America, Scandinavia, and the UK, that implement the 2001 and 2015
editions. Lessons learned in these implementations have been applied in this third edition.
This part of ISO 12006 has also been revised to take into account developments in information technology
(notably building information modelling) and construction procurement. It has been extended and
definitions have been refined to better serve all industry sectors, including building, civil engineering,
infrastructure and process engineering. It continues to serve traditional information technologies and
procurement methods.
0.2  The need for standardization
Building information modelling and modern forms of procurement require that object groupings to be
used. Information management and building information modelling, in particular, is about exchange
of information of all types throughout the asset life cycle, including delivery and operational phases and
between participants and applications. This is also the case for cooperative forms of procurement. For this
exchange to be successful, a complete and consistent approach to object classification is required. This part
of ISO 12006 is intended to facilitate this exchange.
Information types include geometrical data, functional and technical data, and cost and maintenance data
amongst others. The asset lifecycle runs from inception to eventual deconstruction. Participants include
clients and owners, designers, authorities, constructors, end users, and operators. Applications include
modelling, specification, product information, and cost information systems.
Overarching principles for classification and breakdown structures are also needed for different
international and national reporting, so that quantities and values are defined according to the same
principles and are comparable. These values and quantities can be related to sustainability and financing.
While national classifications that implement this part are still likely to differ in their detail (for example,
due to differences in construction, culture and legislation), mapping between them can be aided if they are
using the same overarching classification and breakdown structure frameworks. This, in turn, can help with
international project work (with participants from many countries), and with development of applications
intended to be used internationally.
0.3  Breakdown structures and classification structures
Information structuring is critical to the delivery of the information purposes. Information purposes can
be expressed in terms of desired outcomes as use-cases, or in terms of specific outputs as documentation.
The purpose of information structures including breakdown structures and classification structures is to
organize concepts hierarchically thereby supporting cataloguing and grouping information and sharing
unambiguous meaning (semantic interoperability) throughout the information and asset lifecycles.
The purpose of a breakdown structure is to organize the decomposition of the domain to support naming of
instances, way-finding and search paths and the management of capacity and performance within a given
context by making distinctions between types of objects.
The purpose of a classification structure is to organize similar types of objects to support searching, sorting,
matching and retrieval.
0.4  Types of structures
According to ISO 22274, classification and breakdown structures can be enumerative, faceted, or a
combination of enumerative and faceted.

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ISO/DIS 12006-2:2024(en)
Enumerative classification systems attempt to list all possible groupings within their defined area of
applicability. They are in many cases represented using hierarchies. A complete enumerative classification
system is often very complex in nature and its basic principles of development can be difficult to identify.
Faceted classification systems allow the assignment of multiple classifications to an object. An object can be
characterized by any combination of the groupings from the facets. By using a combination of enumerative
and faceted classification, the higher levels of the classification system can follow an enumerative approach
to narrow down the areas of applicability of the individual groupings to a manageable size. At the lower level,
faceted approaches are applied to clearly specify the nature of the concepts contained in the leaf groupings
of the classification system.
This document defines a reference breakdown structure for the built environment supported by definitions
and a set of requirements for partial breakdown structures and classification tables. It does not propose the
implementation of a schema or data model.
0.5  Relationship to other standards
This document addresses breakdown and classification structures whereas ISO12006-3 identifies a data
structure for a data dictionary capable of relating concepts using terms relevant to multiple contexts.
ISO 22274 implements content previously proposed as Part 1 of this series. ISO 704 provides criteria for the
definition of concepts.
Annex B illustrates a number of implementations of this document including ISO 81346 series with diagrams
developed from figure 2 and keys to name the included tables. ISO16739-1 is illustrated as a data schema.
0.6  Relationship to earlier versions of this document
This version of ISO 12006:
a. Considers the whole life cycle of the built environment, removing the prefix ‘construction’ from concepts
with wider a.
b. Distinguishes breakdown structures from classification structures.
c. Refines the previous figure 1 (now figure 2) and table 1 to focus on non-abstract concepts.
d. Addition of zones, uncertainty and information purpose whilst maintaining the list of recommended
classification tables and annex listings example.
e. Refines the definitions according to the intensional principal described in ISO 704.

vi
DRAFT International Standard ISO/DIS 12006-2:2024(en)
Building construction — Organization of information about
construction works —
Part 2:
Framework for classification and breakdown structures
1 Scope
This part of ISO 12006 defines a framework for the development of built environment classification systems.
The framework is a breakdown structure supporting the spatial, physical, process aspects along with
relevant resources and support This framework provides a set of recommended classification table titles for
a range of information object groupings according to particular views, e.g., by form or function, supported
by definitions. It shows how the object groupings classified in each table are related, e.g., in a building
information model.
This part of ISO 12006 applies to the complete life cycle of assets, including briefing, design, documentation,
construction, operation and maintenance, demolition and possible reuse of assets or components. It applies
to both building and civil engineering works, including associated engineering services, landscaping and its
natural environment. It is intended for use by organizations which develop and publish such classification
systems and tables, which can vary in detail to suit local needs. When this part of ISO 12006 is applied in the
development of local classification systems and tables, then harmonization between them will be facilitated.
The management of the built environment above the level of complex, entities and project/programmes (for
example geographic catchment areas, asset portfolios, functional requirements and organizational activity)
are outside the scope of this document.
This part of ISO 12006 does not provide the content of the tables, though it does give examples.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 22274, Systems to manage terminology, knowledge and content — Concept-related aspects for developing
and internationalizing classification systems
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
NOTE 1 The definitions are arranged in the following order: structure, objects, spatial aspects, physical aspects,
process aspects, resource aspects and supporting aspects.
NOTE 2 In the definitions, terms that are defined elsewhere within this clause are shown in italics.
NOTE 3 Examples are given in Annex A.

ISO/DIS 12006-2:2024(en)
3.1 Structures
3.1.1
information structure
classification system
hierarchy of named groupings used to organize information for sorting, comparisons and matching, sorting
and retrieval
Note 1 to entry: a hierarchy need not be a tree but, with multiple links, can be a directed network (polyhierarchy), for
example if an occurrence is a member of several groupings.
Note 2 to entry: ISO 22274 defines classification system to include both breakdown and classification structures.
3.1.2
breakdown structure
meronomy
decomposition hierarchy
framework for efficiently controlling aspects of the process, physical and spatial objects of the built
environment
[SOURCE: ISO 27026:2011, 3.1.1; ISO 10795:2019(en), 3.30 [Modified] ]
Note 1 to entry: a breakdown structure comprises a hierarchy of named dissimilar groupings organized by whole-part
or other extrinsic associations such as ‘contains’, ‘bounds’ , ‘enables’, ‘serves’ or ‘specifies’
Note 2 to entry: Clause 5 provides a reference breakdown structure and discusses partial breakdown structures
3.1.3
classification structure
taxonomy
specialization hierarchy
exhaustive set of mutually exclusive categories to aggregate objects at a pre-prescribed level of specialization
for a specific purpose
Note 1 to entry: a classification structure comprises a hierarchy of named similar groupings organized by type-of
relationships based on intrinsic properties
Note 2 to entry: Clause 6 provides requirements for the development and application of classification structures
[SOURCE: ISO 17115:2007, 2.7.1; ISO/TS 22558:2019, 3.3, modified - data replaced with objets]
3.2 Objects
3.2.1
object
any part of the perceivable or conceivable world
Note 1 to entry: An object is something abstract or physical toward which thought, feeling, or action is directed.
Note 2 to entry: Previously ‘construction object’
3.2.3
built environment
built asset
managed environment
infrastructure
artificial aspect of the environment
Note 1 to entry: The built environment can be viewed spatially as a collection of spaces and/or physically as a collection
of components and/or as process as a collection of tasks.
EXAMPLE towns, drainage
ISO/DIS 12006-2:2024(en)
3.2.4
natural environment
non-artificial aspect of the environment
EXAMPLE hills, rainfall
3.3 Asset related
3.3.0
asset
item, thing or entity that has potential or actual value to an organization
[SOURCE: ISO 55000:2014, 3.2.1, modified - The notes to entry have been removed.]
3.3.1
complex
construction complex
site
set of entities serving intended to serve a common function or user activity
Note 1 to entry: a complex is intended to serve at least one function or user activity within a geo-spatial boundary.
Note 2 to entry: See A.9. Previously ‘construction complex’
EXAMPLE Airport, Motorway, Hospital. An airport, business park, motorway. e.g., an airport typically is composed
of the entities such as runway, control tower, terminal building, aircraft hangar, etc. A business park typically is
composed of a number of buildings, access roads, and landscaping (each an object in its own right). A motorway from A
to B typically is composed of service stations, the motorway pavement, bridges, embankments, landscaping, etc.
3.3.2
zone
spatial extent that has characteristics that distinguishes it from other spatial extents
Note 1 to entry: Characteristics can relate to regulations, purposes, or functions.
Note 2 to entry: Zone can be part of, as well as an aggregation of, other spatial extents such as spaces.
Note 3 to entry: Zones need not be mutually exclusive, so spaces can be assigned to multiple zones. Zones therefore
can serve rather than be part of the complex.
Note 4 to entry: Zones can be hierarchical, if the common factor is amenable to disaggregation
Note 5 to entry: the set of spaces in a Zone need not be contiguous
Note 6 to entry: See A.15
EXAMPLE access zone, fire safety zone, climate zone, smoking area, quiet zone.
3.3.3
space
built space
location
area
spatial extent defined physically or notionally
Note 1 to entry: identified spatial extent in 2 or 3 dimensions having a common purpose or other property, defined
physically or notionally
Note 2 to entry: A space can be defined by activity, bounds or work extent.
Note 3 to entry: See 5.2.1 and A.10 . Previously ‘construction space’ or ‘activity space’
EXAMPLE Traffic lane, bedroom, room defined by floor, ceiling, and walls, footpath, power-line corridor defined
by natural forest.
ISO/DIS 12006-2:2024(en)
3.3.4
entity
construction entity
facility
building
structure
independent unit of the built environment with a characteristic form and spatial structure, intended to serve
at least one function or user activity
Note 1 to entry: An entity is intended to serve at least one function or user activity. It is recognizable as a physically
independent object even though a number of entities might be seen as parts of a particular complex. Ancillary works
such as access roads, landscaping, service connections, can be regarded as part of an entity or if the ancillary works
are of sufficient scale, they can be regarded as entities in their own right.
Note 2 to entry: See A.9. Previously ‘construction entity’.
EXAMPLE bridge, hotel, car park
3.3.5
element
functional system
system
construction element
set of components with a characteristic function, form or position
Note 1 to entry: ISO 81346 uses ‘object with characteristics which predominantly represents an overall inherent
function’
Note 2 to entry: Components can be part of one or more elements and need not be contiguous. Elements therefore
serve an entity rather than be part of the entity.
Note 3 to entry: Elements can be hierarchical, with higher level functions being disaggregated into lower-level
(technical) systems. a single technical system (such as a wall system) can satisfy several elements or many technical
systems can satisfy a single element (such as a security system)
Note 4 to entry: The concept of element is used in a broad sense, not linked to any specific domain or discipline.
Note 5 to entry: See A.11. Previously ‘construction element’
EXAMPLE Load-bearing system, roof system, wall system, HVAC system, drainage system, electrical system,
communication system, transportation system, planting system, landscape system, window system, suspension
system, hinge system, fan system.
3.3.6
component
material or manufactured item used as a constituent in an assembled product, technical system or plant
Note 1 to entry: A component is generally incorporated in a permanent manner in an entity. Otherwise, this would be
an aid (3.6.2). Components can initially be resources.
Note 2 to entry: See A.3. Previously ‘construction product’
EXAMPLE a lighting pole, a door, a beam
3.3.6.1
technical system
element or system defined by its providing a coherent technical solution enabling one or more elements
Note 1 to entry: ISO 81346 uses ‘object with characteristics which predominantly represents a coherent technical
solution with an inherent function’

ISO/DIS 12006-2:2024(en)
3.3.6.2
product or material
product
material
construction product
specification of properties common to a number of components (3.4.4)
EXAMPLE door unit, material, soil type
3.4 Process
3.4.0
process
set of interrelated or interacting activities that use inputs to deliver an intended result
[SOURCE: ISO 9000:2015, 3.4.1, modified - The notes to entry have been removed.]
3.4.1
management
project
programme
coordinated activities to direct and control
[SOURCE: ISO 9000:2015, 3.3.3, modified – The words “an organization” have been removed.]
Note 1 to entry: Typically coordinated activities directed towards the accomplishment of agreed objectives
Note 2 to entry: See A.6
EXAMPLE new-build, renovation
3.4.2
activity
work package
work section
work result
identified piece of work that is required to be undertaken to complete a process
[SOURCE: ISO 10006:2017, 3.1, modified – The word “project” has been replaced with “process”.]
Note 1 to entry: These can be hierarchical, if the package is amenable to disaggregation of tasks for sub-contracting or
delegation.
Note 2 to entry: A package can be enabling, creating resources.
Note 3 to entry: See A.12. Previously ‘work result’
EXAMPLE steel framing, groundworks, fire engineering
3.4.3
task
set of activities required to achieve a result
[SOURCE: ISO 6707-2:2017, 3.2.55, modified – The word “activities” has been replaced with “set of activities”.
The word “goal” has been replaced with “result”.]
Note 1 to entry: a task can use resources (3.6) to affect components (3.4.4)
Note 2 to entry: See A.7. Previously ‘construction process’
EXAMPLE a preparation task, an execution task, a finishing-off task

ISO/DIS 12006-2:2024(en)
3.5 Resource
3.5.0
resource
object used in a process to achieve a result
3.5.1
actor
agent
person, organization or organizational unit involved in a process
Note 1 to entry: Organizational units include, but are not limited to, departments, teams
EXAMPLE supervisor, engineer, labourer.
3.5.2
aid
construction equipment
construction aid
temporary works
resource which supports an actor
Note 1 to entry: An aid is generally temporary. An object intended for permanent incorporation is a component.
Note 2 to entry: See A.5: Previously ‘construction aid’
EXAMPLE scaffolding, bracing, hammer, excavator.
3.5.3
information
construction information
meaningful data
[SOURCE: ISO 9000:2015, 3.8.2]
Note 1 to entry: See A.2. Previously ‘construction information’
EXAMPLE map, model, drawing, specification, product data sheet
3.6 Supporting aspects
3.6.1
property
defined characteristic suitable for the description and differentiation of an object (3.2.1)
[SOURCE: ISO 22274:2013, 3.25, modified - The words "the objects in a class" have been replaced with "an
object". The Example has been removed.]
Note 1 to entry: a property is expected to reflect current or past characteristics
Note 2 to entry: See A.13. Previously ‘construction property’
EXAMPLE name, description, classification, volume, density, duration
3.6.2
uncertainty
risk/opportunity
lack of certitude resulting from inaccuracies in, or lack of, information
Note 1 to entry: Uncertainties can be expressed as opportunities and risks, reflecting choices associated with future
spatial, physical and activity aspects of the built environment
Note 2 to entry: See A.15
ISO/DIS 12006-2:2024(en)
EXAMPLE fall from height, energy saving
3.6.3
information purpose
intention or objective for which information is created for
Note 1 to entry: See A.16
4 Principles for structuring information for the built environment
4.1 Concept model
Information structuring for the built environment shall address the spatial and physical asset, the processes
and the resources involved so as to support its description and narration as shown in Figure 1.
NOTE The built environment is experienced and exploited spatially, created physically and is affected (designed,
constructed and operated) through processes which are effected through using resource. Conversely, resources are
used to effect processes which affect entities which contain complexes.
Figure 1 — Narrative (left to right) and descriptive (right to left) view
Figure 2 — Recommended classification tables for objects
Objects labelled © shall have classification tables. *Components can initially be considered as resources.
*Information can ultimately be considered as an asset.

ISO/DIS 12006-2:2024(en)
Figure 2 and Table 1 should be read together with further detail in relation to each aspect in Clause 5 and
the details on implementation in Clause 7.
NOTE Figure 2 is not intended to define a data-model.
4.2 Information structures
Structured information shall be used to support information management for the built environment.
Breakdown structures shall create a hierarchy predominantly based on decomposition, whereas
classification structures shall create a purely specialization hierarchy.
NOTE Whilst such structures are hierarchical, breakdown structures need not be a strict tree, since the presence
of horizontal relationships such as ‘serves’ can create a ‘directed network’ (polyhierarchy) where branches converge
on a common terminal leaf. as when an occurrence is a member of several management groupings.
As an illustration, Figure 3 shows on the left a wall assembly is decomposed into studs, insulation and plates
components and a ventilation element is decomposed into fans, insulation and ductwork, whereas on the
right a ventilation system is specialized down to passive, hybrid and mechanical elements, and insulation
components is specialized down into wall batts and duct insulation.
Figure 3 — Illustration of a breakdown structure (left) and a classification structure (right)
As an illustration, Figure 4 shows the combination of a breakdown structure and classification structure
where a window frame component can be a part of window component which is part of a wall technical
system. The window can be classified by its mode of operation, but its glazing components can be classified
by its number of glass layers.
Figure 4 — Illustration of combining breakdown and classification structures

ISO/DIS 12006-2:2024(en)
NOTE Figures 3 and 4 illustrates the principle behind each kind of hierarchy (type-of and part-of). The graphic
representation is based on ISO 1087, Annex A.1. They serve to illustrate the principle and do not attempt to standardize
any class, sub-class, whole, or part.
4.3 Breakdown structures
Breakdown structures shall be distinguished in that they apply extrinsic relationships to create each level,
so that breakdown structures shall contain different kinds of objects.
NOTE Breakdown structures are often relevant to the analysis of outcomes and outputs.
The breakdown structure approach shall handle wholes as distinct from parts and also associations such as
‘is-enabled-by’ and ‘specifies’. By identifying related types of objects, the relationships among these shall be
determined, and monitored, to ensure that all objects are similarly related.
NOTE An object is a part if when added to a whole, the whole still remains.
EXAMPLE If a brick is added to or subtracted from a wall system, the whole is still a wall system, or if a wall
system is added to an object, the whole is still that object.
Examples
— using a functional aspect, the function of a part is fundamental to the function of the whole;
— using a spatial aspect, the spatial extension of a part is included in that of the whole;
— using an assembly aspect, the part-whole relation means that the existence of a physical part precedes the existence
of the whole.
4.4 Classification structures
Classification structures shall be distinguished in that they apply intrinsic properties to create each level, so
that classification structures shall contain the same kind of objects.
NOTE Classification is often relevant to the management of inputs such as libraries and information resources.
A classification table shall define the type of object in the classification. Then the properties of interest to
the classification shall be distinguished, and finally the objects shall be assigned by considering the chosen
properties.
For the classification to be exhaustive, every object in the collection shall be assignable to a grouping, and in
order to be distinct, the groupings shall be mutually exclusive, meaning that any specific object only belongs
to one group.
Groupings shall be defined by descriptions indicating the properties representing the attributes of interest.
The properties common to the whole collection shall be determined so that the resulting group is the most
general in the classification. The general grouping shall be subdivided into more specialized groupings in
several steps. The subdivision shall result in groupings that run from the general to the specialized. The
groupings shall be ordered in levels determined by the type-of relation, where specific groupings are types
of more general groupings
Groupings shall be divided into sub-groupings by a principle of specialization, resulting in a classification
table. If there is a second principle of specialization for a particular grouping, then this shall be applied
separately so that another classification table generated.
EXAMPLE A group representing furniture should not be divided into sub-groups such as “office furniture”,
“domestic furniture”, “metal furniture”, “wooden furniture” because a given object can belong to more than one sub-
division.
ISO/DIS 12006-2:2024(en)
4.5 Characteristics
4.5.1 Properties
Objects being structured shall have properties. These properties shall be used for grouping, to define and to
subdivide the objects for classification.
4.5.2 Uncertainty
Uncertainties such as risks and opportunities represent potential change in the built environment and arise
from the spatial, physical and process context.
NOTE Uncertainty can be associated to one or more than one objects in terms of causation and in terms of effect.
Risks can be managed and treated, whereas opportunities can be enabled and promoted.
4.5.3 Information purposes
Information purposes shall be defined to organize the production of information and the management of the
interventions in the built environment. Reference breakdown structure and recommended classification tables
The reference breakdown structure which is shown in figure 2 and is summarized in table 1 shall be used to
organize information structuring.
NOTE Table 1 shows the minimum set of classification tables by aspects along with the suggested criteria when
developing specialization with cross-references to definitions in clause 3 and examples in Annex A. Implementations
can choose to not offer all of these tables. Examples are given in Annex B
Table 1 — Summary of recommended classification tables
Definition reference Table Example criteria Annex A reference
3.3 Asset
3.3.1 Complex — function, A.8
3.3.2 Zone A.14
— form,
— user,
3.3.4 Space A.10
— service
3.3.4 Entity — function, — position, A.9
3.3.5 Element A.11
— form, — material,
3.3.6 Component A.3
— activity, — medium
3.4 Process
3.4.1 Control — activity, A.6
3.4.2 Activity A.12
— stage,
— resource,
3.4.5 Task A.7
— material
3.5 Resource
— discipline,
3.5.1 Actor A.4
— role
— function, — user,
3.5.2 Aid A.5
— form, — permanence
ISO/DIS 12006-2:2024(en)
TTabablele 1 1 ((ccoonnttiinnueuedd))
Definition reference Table Example criteria Annex A reference
— content,
3.5.3 Information A.2
— form
3.6 Supporting
3.6.1 Property — intrinsic / extrinsic A.13
— impact,
3.6.2 Uncertainty — causal factors, A.15
— consequence
— strategic goals,
3.6.3 (Information) Purposes — management controls, A.16
— detailed operations
4.6 Partial breakdown structures
Partial breakdown structures shall be based on the reference breakdown structure so as to create links to
the equivalent classification structures.
Partial breakdown structures shall use a limited number of levels, typically 3-5.
EXAMPLE Complex – Entity – Space
EXAMPLE Entity – Element – Component
EXAMPLE Entity – Component – Product or Material
EXAMPLE Product or Material – Space – Element (see ISO 81346—1)
EXAMPLE Element – Product or Material – Space (see ISO 81346—10)
NOTE Parti
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