oSIST prEN ISO 7817:2023

SLOVENSKI STANDARD
oSIST prEN ISO 7817:2023
01-september-2023
Informacijsko modeliranje gradenj - Raven informacijskih potreb - 1. del: Pojmi in
načela (ISO/DIS 7817:2023)
Building Information Modelling - Level of Information Need - Part 1 Concepts and
principles (ISO/DIS 7817:2023)
Bauwerksinformationsmodellierung - Informationsbedarfstiefe - Teil 1: Konzepte und
Grundsätze (ISO/DIS 7817:2023)
Modélisation des informations de la construction (BIM) - Niveau du besoin d'information -
Concepts et principes (ISO/DIS 7817:2023)
Ta slovenski standard je istoveten z: prEN ISO 7817
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
oSIST prEN ISO 7817:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 7817:2023

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oSIST prEN ISO 7817:2023
DRAFT INTERNATIONAL STANDARD
ISO/DIS 7817.2
ISO/TC 59/SC 13 Secretariat: SN
Voting begins on: Voting terminates on:
2023-07-20 2023-09-14
Building information modelling — Level of information
need — Concepts and principles
Modélisation des informations de la construction (BIM) — Niveau du besoin d'information — Concepts et
principes
ICS: 35.240.67; 91.010.01
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
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NATIONAL REGULATIONS.
ISO/DIS 7817.2:2023(E)
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
DRAFT INTERNATIONAL STANDARD
ISO/DIS 7817.2
ISO/TC 59/SC 13 Secretariat: SN
Voting begins on: Voting terminates on:

Building information modelling — Level of information
need — Concepts and principles
Modélisation des informations de la construction (BIM) — Niveau du besoin d'information — Concepts et
principes
ICS: 35.240.67; 91.010.01
This document is circulated as received from the committee secretariat.
COPYRIGHT PROTECTED DOCUMENT
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
© ISO 2023
ISO/CEN PARALLEL PROCESSING
THEREFORE SUBJECT TO CHANGE AND MAY
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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NATIONAL REGULATIONS.
Website: www.iso.org ISO/DIS 7817.2:2023(E)
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ii
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PROVIDE SUPPORTING DOCUMENTATION. © ISO 2023

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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General . 3
5 Framework to specify the level of information need . 3
5.1 General . 3
5.2 Consider the purposes . 4
5.3 Consider the information delivery milestones . 4
5.4 Consider the actors . 4
5.5 Consider the objects within a breakdown structure . 5
6 Definition of level of information need and its subdivision . 5
6.1 General . 5
6.2 Geometrical information . 6
6.2.1 General . 6
6.2.2 Detail . 6
6.2.3 Dimensionality . 9
6.2.4 Location . 10
6.2.5 Appearance . 10
6.2.6 Parametric behaviour . 11
6.2.7 Relationships of aspects of geometrical information and prerequisites .12
6.3 Alphanumerical information .12
6.3.1 General .12
6.3.2 Identification .12
6.3.3 Information content .12
6.4 Documentation .13
6.5 Relationship diagram on level of information need . 13
7 Verification and validation .14
Annex A (informative) Overview of the main concepts related to information exchange .16
Annex B (informative) Example of method to specify level of information need.17
Bibliography .21
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
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 (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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by the European Committee for Standardization (CEN) Technical
Committee CEN/TC 442, Building Information Modelling (BIM) (as EN 17412-1:2020) and drafted in
accordance with its editorial rules. It was assigned to Technical Committee ISO/TC 59, Buildings and
civil engineering works, Subcommittee SC 13, Organization and digitization of information about buildings
and civil engineering works, including building information modelling (BIM) and adopted under the “fast-
track procedure”.
A list of all parts in the ISO 7817 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
Introduction
This document sets out the concepts and principles for defining the level of information need and
information deliveries being part of the information exchange processes during the life cycle of built
assets when using building information modelling (BIM). Those concepts and principles can deliver
clear benefits to all participants in the various life cycle phases of built assets as they provide a common
understanding on the right level of information needed at a certain time. One purpose of defining the
level of information need is to prevent delivery of too much information. Information exchange should
ensure the required information to be delivered at the agreed time for the agreed purpose to facilitate
verification and validation processes.
This document provides methods for describing information to be exchanged according to exchange
information requirements. The exchange information requirements specify the wanted information
exchange. The result of this process is an information delivery.
There is a need that these concepts and principles are described in a common and comparable way to
allow services related to building information modelling to be procured and offered on a global scale.
The need has arisen by the fact that there are several conflicting terms, concepts and usages in place,
internationally, that hinder the objective of having a common understanding and practise in describing
the level of information need. It is therefore helpful not to use an acronym to refer to level of information
need as this can oversimplify these concepts.
The concepts and principles contained in this document are aimed at all those involved in the asset life
cycle. This includes, but is not limited to, the asset owner/operator, the client, the asset manager, the
design team, the construction team, an equipment manufacturer, a technical specialist, a regulatory
authority, an investor, an insurer and an end-user.
The information exchange, as well as related topics such as the exchange information requirements and
the information delivery are defined and explained in context of two related standards:
ISO 19650-1, Organization and digitization of information about buildings and civil engineering works,
including building information modelling (BIM) — Information management using building information
modelling — Part 1: Concepts and principles; and
ISO 29481-1, Building information models — Information delivery manual — Part 1: Methodology and
format.
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oSIST prEN ISO 7817:2023

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oSIST prEN ISO 7817:2023
DRAFT INTERNATIONAL STANDARD ISO/DIS 7817.2:2023(E)
Building information modelling — Level of information
need — Concepts and principles
1 Scope
This document specifies concepts and principles to establish a methodology for specifying level of
information need and information deliveries in a consistent way when using building information
modelling (BIM).
This document specifies the characteristics of different levels used for defining the detail and extent
of information required to be exchanged and delivered throughout the life cycle of built assets. It gives
guidelines for principles required to specify information needs.
The concepts and principles in this document can be applied for a general information exchange and
while in progress, for a generally agreed way of information exchange between parties in a collaborative
work process, as well as for an appointment with specified information delivery.
The level of information need provides methods for describing information to be exchanged according
to exchange information requirements. The exchange information requirements specify the wanted
information exchange. The result of this process is an information delivery.
This document is applicable to the whole life cycle of any built asset, including strategic planning,
initial design, engineering, development, documentation and construction, day-to-day operation,
maintenance, refurbishment, repair and end-of-life.
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 29481-1:2016, Building information models — Information delivery manual — Part 1: Methodology
and format
ISO 6707-1:2020, Buildings and civil engineering works — Vocabulary — Part 1: General terms
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 29481-1:2016, ISO 6707-1 and
the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at https:// www .electropedia .org/
— ISO Online browsing platform: available at https:// www .iso .org/ obp
3.1
information container
named persistent set of information (3.11) retrievable from within a file, system or application storage
hierarchy
EXAMPLE Including sub-directory, information file (including model, document, table, schedule), or distinct
sub-set of an information file such as a chapter or section, layer or symbol.
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
Note 1 to entry: Persistent information exists over a timescale long enough for it to have to be managed, i.e. this
excludes transient information such as internet search results.
Note 2 to entry: Naming of an information container should be according to an agreed naming convention.
[SOURCE: ISO 19650-1:2018, 3.3.12, modified - Note 1 to entry has been removed]
3.2
information delivery milestone
scheduled event for a predefined information exchange
[SOURCE: ISO 19650-2:2018, 3.1.3.2]
3.3
information exchange
act of satisfying an information requirement or part thereof
[SOURCE: ISO 19650-1:2018, 3.3.7]
3.4
information model
set of structured and unstructured information containers (3.1)
[SOURCE: ISO 19650-1:2018, 3.3.8]
3.5
level of information need
framework which defines the extent and granularity of information (3.11)
Note 1 to entry: One purpose of defining the level of information need is to prevent delivery of too much
information.
[SOURCE: ISO 19650-1:2018, 3.3.16]
3.6
verification
confirmation, through the provision of objective evidence, that specified requirements have been
fulfilled
[SOURCE: ISO 9000:2015, 3.8.12, modified — Notes 1 to 3 to entry have been removed]
3.7
validation
confirmation, through the provision of objective evidence, that the requirements for a specific intended
use or application have been fulfilled
[SOURCE: ISO 9000:2015, 3.8.13, modified — Notes 1 to 3 and cross references have been removed]
3.8
breakdown structure
decomposition of a defined scope into progressive levels
[SOURCE: ISO 21511:2018, 3.13 modified — “work” has been deleted from the term, “scope of the project
and programme” has been replaced with “scope”, “progressively lower levels consisting of elements of
work” has been replaced with “progressive levels”]
3.9
object
any part of the perceivable or conceivable world
[SOURCE: ISO 12006-2:2015, 3.1.1, modified — Note 1 to entry has been removed]
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
3.10
geometry
shape, size, and location of an object (3.9)
[SOURCE: ISO/IEC 13249-3:2016, 3.1.2.27, modified — “size” has been added, “geographic location” has
been replaced with “location”, “feature” has been replaced with “object”]
3.11
information
meaningful data
[SOURCE: ISO 9000:2015]
3.12
geometrical information
information (3.11) expressed using geometry (3.10)
3.13
alphanumerical information
information (3.11) expressed using characters, digits and symbols or tokens
EXAMPLE Mathematical symbols and punctuation marks are such tokens.
3.14
documentation
collection of documents related to a given subject
[SOURCE: ISO 82045-1:2001, 3.2.4, modified — Notes to entry 1 to 4 have been removed]
3.15
information deliverable
information container (3.1) used to fulfil an appointment
4 General
To support information exchange, level of information need should be used.
The level of information need provides a framework for describing information exchanged in terms
of geometrical information, alphanumerical information and documentation. Different purposes have
their own needs of geometrical information, alphanumerical information and documentation.
The level of information need should be used to discuss and agree on the information delivery between
two or more actors.
The level of information need describes information requirements that can be human-readable and
machine-interpretable.
5 Framework to specify the level of information need
5.1 General
In specifying the level of information need and how information is going to be delivered the following
prerequisites shall be considered:
— purposes for the use of the information to be delivered;
— information delivery milestones for the delivery of the information;
— actors who are going to request and actors who are going to deliver the information;
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
— objects organized in one or more breakdown structures.
The specification of level of information need is informed by but does not include the listed prerequisites
(see also Figure 8 in 6.5 for the relationship between the prerequisites and the level of information
need).
See Annex A for more information related to the conceptual relationships between this document,
ISO 19650-1 and ISO 29481-1.
5.2 Consider the purposes
In specifying the level of information need, the purposes for information delivery shall be considered.
The purposes should be specified to clarify why the information is needed. The level of information
need should be used for the purposes it has been required for.
The level of information need does not specify the purposes.
To achieve the same purpose, the geometrical information, alphanumerical information and
documentation can vary for different objects.
EXAMPLE 1 To perform an accessibility analysis, properties such as the clear opening width of a door, its
location, the position and shape of the handle are needed. Other properties, such as the name of the manufacturer
and the acquisition cost, are not relevant to fulfil the purpose. On the other hand, for cost analysis purpose, the
acquisition cost of a door is needed, but the appearance of the handle is not relevant. For rendering purpose, the
geometrical appearance of a door is relevant, while the name of the manufacturer and the acquisition cost are
not.
At an information delivery milestone, the same level of information need required for an object can be
used for different purposes.
EXAMPLE 2 In concept design, the same geometry and information of a block can be used for clash detection
and quantity take off.
In some cases, the purpose should not be explicit to all actors (e.g. for security reasons). In those cases,
the purpose should be considered as “not disclosed” and only authorized actors should be informed.
EXAMPLE 3 The purposes can be extracted from organizational information requirements, project
information requirements and asset information requirements as described in ISO 19650-1:2018 5.2, 5.3, 5.4 and
ISO 19650-2:2018, 5.1.2.
5.3 Consider the information delivery milestones
In specifying the level of information need, information delivery milestones shall be considered.
The information delivery milestones should be specified to clarify when the information is needed.
The level of information need does not specify the information delivery milestones.
At the same information delivery milestone, the geometrical information, alphanumerical information
and documentation can vary for different objects.
EXAMPLE 1 To do accessibility analysis, usually the same level of information need is required at different
milestones.
EXAMPLE 2 To do energy analysis, different level of information need is required at different milestones.
5.4 Consider the actors
In specifying the level of information need, actors who require and deliver the information shall be
considered.
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
The level of information need does not specify the actor (actors).
EXAMPLE 1 The same level of information need can be required by different actors at the same milestone to
fulfil different purposes.
EXAMPLE 2 Different level of information need can be required by different actors at the same milestone to
fulfil the same purpose.
NOTE 1 At different milestones, e.g. especially in the early phase, the actor responsible of delivering specified
level of information need might not be specified.
EXAMPLE 3 A client might ask for a specific level of information need for an object at an agreed information
delivery milestone without specifying who needs to deliver it. In this case the supply chain is free to assign
responsibilities as preferred.
NOTE 2 Different actors can be responsible for different level of information need at the same information
delivery milestone to fulfil the same purpose.
NOTE 3 For design purposes, at an agreed information delivery milestone, a wall in a project can be
made up of a structural element, architectural cladding and an air duct penetration with an air duct passing
through the penetration. Mechanical, electrical and plumbing engineers are responsible for providing reliable
information concerning the sizing of the duct and associated desired penetration sizing so that the structural
and architectural teams can continue their work to respectively validate the wall structure and cladding design.
5.5 Consider the objects within a breakdown structure
In specifying the level of information need, the objects within a breakdown structure for the information
delivery shall be considered.
The level of information need does not specify the objects within a breakdown structure.
To be able to specify the level of information need, the considered objects within a breakdown structure
should be specified, identifying the semantic, functional and/or spatial decomposition of the project
into objects (e.g. construction elements and spaces are identified) or any other breakdown structure.
NOTE 1 Based on the purpose, the level of information need can be related to:
1) Construction results (spaces, construction complexes, construction entities and construction
elements);
2) Construction information (information model, building model, specification, documentation,
diagram).
NOTE 2 Breakdown structures can follow a classification system, systems engineering principles or a
federation strategy.
NOTE 3 Different purposes can require different breakdown structures and derived decompositions.
EXAMPLE 1 To fulfil the purpose of cost estimation during the construction phase, a breakdown structure
can be different from a breakdown structure required for scheduling.
6 Definition of level of information need and its subdivision
6.1 General
The level of information need is the framework which defines the extent and granularity of information
to be exchanged. In accordance with this standard the level of information need should be described by
different concepts: geometrical information, alphanumerical information and documentation.
The level of information need can be answered by a combination of geometrical information,
alphanumerical information and/or documentation (see Annex B).
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oSIST prEN ISO 7817:2023
ISO/DIS 7817.2:2023(E)
Information contained within documentation, geometrical information and alphanumerical information
can overlap and/or be contradictory, which can create consistency problems within the information
model. A clear hierarchy of the information provided within different information containers should
then be established.
Level of information need can either be predefined or can be defined for a particular information
delivery.
NOTE 1 A predefined level of information need can be included in regulations, standards, plans of work,
recommendations or specific project requirements; while other level of information need can be project specific.
If an aspect of lev
...