ISO 6284:2023
(Main)Technical product documentation - Construction documentation - Indication of limit deviations
Technical product documentation - Construction documentation - Indication of limit deviations
This document specifies methods for the indication of limit deviations on construction documents.
Documentation technique de produits — Documentation de construction — Indication des écarts limites
Le présent document spécifie les méthodes à utiliser pour indiquer les écarts limites sur les documents de construction.
General Information
- Status
- Published
- Publication Date
- 29-May-2023
- Technical Committee
- ISO/TC 10/SC 8 - Construction documentation
- Drafting Committee
- ISO/TC 10/SC 8 - Construction documentation
- Current Stage
- 6060 - International Standard published
- Start Date
- 30-May-2023
- Due Date
- 02-Feb-2024
- Completion Date
- 30-May-2023
Relations
- Effective Date
- 06-Jun-2022
Overview
ISO 6284:2023 - Technical product documentation - Construction documentation - Indication of limit deviations - specifies standardized methods for showing limit deviations on construction documents. The third edition updates guidance to support both traditional graphical drawings and machine‑readable data templates (BIM), and clarifies types and notations for upper and lower limit deviations relative to a target size.
Key topics and requirements
- When to indicate deviations: Limit deviations are required only where a functional requirement exists to control position, dimension, orientation or form.
- Reference convention: The target size is the sole reference for expressing deviations; upper and lower limit deviations are signed values.
- Two indication methods:
- Dimensions on construction drawings - numerical indications placed with or adjacent to the concerned size; use millimetres or metres for linear sizes. Symmetrical tolerances use ±, zero must be shown explicitly as “0”, angular tolerances may be given in decimal degrees or degrees/minutes/seconds.
- Property items in data templates (BIM) - limit deviations represented as structured property groups for machine‑readability.
- Property items required (for data templates): DeviationType, ReferenceTo (if applicable), DesiredValue (e.g., TargetSize/TargetAngle/TargetXCoordinate), UpperLimitDeviation, LowerLimitDeviation. The standard recommends using PascalCase naming for properties.
- Deviation type designations: common abbreviations are provided (e.g., LD = Length deviation, AD = Angular deviation, PL = Profile/Position deviation of a line, SL = Straightness deviation, SS = Shape deviation, FS = Flatness deviation, SK = Skewness, PP = Position deviation of a point, VD/HD = Verticality/Horizontality).
- Presentation rules: Examples illustrate asymmetrical vs symmetrical tolerances, positional tolerances for locating objects, profile and straightness deviations, and how to number or provide coordinates for points.
Practical applications
- Ensures consistent, unambiguous tolerance and deviation information in construction drawings and digital models.
- Supports quality control, prefabrication coordination and site installation by defining acceptable limits for manufactured elements and on‑site work.
- Facilitates interoperable exchange of tolerance data in BIM workflows and automated checking or fabrication processes.
- Useful for drafting CAD standards, preparing factory/fabrication packages, and specifying inspection criteria.
Who should use this standard
- Architects, structural and civil engineers
- CAD/BIM managers and modelers
- Manufacturers of prefabricated building components
- Contractors, quality inspectors and surveyors
- Standards writers and technical documentation specialists
Related standards
- ISO 286-1 (tolerances and deviations on linear sizes)
- ISO 6707-1 (vocabulary for buildings/civil engineering)
- ISO 9431 (drawing layout)
- ISO 23387 (data template methodology for digital construction information)
Frequently Asked Questions
ISO 6284:2023 is a standard published by the International Organization for Standardization (ISO). Its full title is "Technical product documentation - Construction documentation - Indication of limit deviations". This standard covers: This document specifies methods for the indication of limit deviations on construction documents.
This document specifies methods for the indication of limit deviations on construction documents.
ISO 6284:2023 is classified under the following ICS (International Classification for Standards) categories: 01.100.30 - Construction drawings. The ICS classification helps identify the subject area and facilitates finding related standards.
ISO 6284:2023 has the following relationships with other standards: It is inter standard links to ISO 6284:1996. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
You can purchase ISO 6284:2023 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of ISO standards.
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 6284
Third edition
2023-05
Technical product documentation —
Construction documentation —
Indication of limit deviations
Documentation technique de produits — Documentation de
construction — Indication des écarts limites
Reference number
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General . 2
4.1 Generality . 2
4.2 Application . 2
4.3 Designations of deviation types . 2
5 Indication of limit deviations .3
5.1 As dimensions on construction drawings or figures within notes . 3
5.2 As property items within data templates . 5
Bibliography .11
iii
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
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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.
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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 Technical Committee ISO/TC 10, Technical product documentation,
Subcommittee SC 8, Construction documentation.
This third edition cancels and replaces the second edition (ISO 6284:1996), which has been technically
revised.
The main changes are as follows:
— validation of normative references;
— consideration of multiple categories of deviations;
— definitions of indications of limit deviations using building information modelling (BIM).
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.
iv
Introduction
Deviations are a common part of the built environment which are often left to operatives on site to
resolve. With the development of prefabrication, there is recognition that control of deviations is an
essential requirement to improve the quality of building and infrastructure works. It is important for
architectural designers, product manufacturers and constructors to indicate limit deviations and work
to these, where they exist.
The previous edition, ISO 6284:1996, pointed out some basic principles and ways to indicate limit
deviations. It focused on graphical presentations, generally drawings, as a method for delivering
construction and product information. Technically, limit deviations are about not only geometric
information but also the requirements, which shall be delivered objectively by parties to a project.
The digitization of construction requires both graphical and alphanumeric information to be presented
in a formal way to achieve both human-readability and machine-readability.
Data templates are a formal representation method adopted widely to describe exchange information
or product specifications for machine-readability. ISO 23387 has been developed to support digital
processes using formats which are machine-interpretable, based upon standardized data structures, to
exchange information about any type of construction object.
This document focuses on how to provide indication methods for limit deviations that are humanly
recognizable, which is essential given that humans are ultimately the decision-makers, even though
more and more tasks are carried out with the assistance of computers. Therefore, this document
provides two ways to indicate limit deviations:
a) classical graphical or symbolic representations;
b) natural language property items for data templates.
The illustrations included in this document are intended to illustrate the text and/or to provide
examples of the related technical drawing specification. These illustrations are not fully dimensioned
and toleranced, showing only the relevant general principles.
v
INTERNATIONAL STANDARD ISO 6284:2023(E)
Technical product documentation — Construction
documentation — Indication of limit deviations
1 Scope
This document specifies methods for the indication of limit deviations on construction documents.
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 286-1:2010, Geometrical product specifications (GPS) — ISO code system for tolerances on linear sizes
— Part 1: Basis of tolerances, deviations and fits
ISO 6707-1:2020, Buildings and civil engineering works — Vocabulary — Part 1: General terms
ISO 9431, Construction drawings — Spaces for drawing and for text, and title blocks on drawing sheets
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 286-1 and ISO 6707-1 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
construction document
document which specifies construction information
Note 1 to entry: A construction document can be a drawing or a document used to convey or record construction
requirements.
Note 2 to entry: See ISO 5127:2017, 3.1.1.38 for more information about the term “document”.
3.2
data template
schema providing a data structure used to describe the properties of objects
[SOURCE: ISO 23387:2020, 3.3, modified — Definition revised, examples and notes to entry removed.]
3.3
limit deviation
upper limit deviation (3.4) or lower limit deviation (3.5) from target size (3.6)
Note 1 to entry: In this document, “target size” is used for applying deviations to comply with the conventions in
the built environment sector, while “nominal size” is commonly used in engineering fields.
Note 2 to entry: See ISO 6707-1:2020, 3.7.2.6 for more information about the term “deviation”.
[SOURCE: ISO 286-1:2010, 3.2.5, modified — Definition modified and notes to entry added.]
3.4
upper limit deviation
upper limit of size minus target size (3.6)
Note 1 to entry: Upper limit deviation is a signed value and may be negative, zero or positive.
[SOURCE: ISO 286-1:2010, 3.2.5.1, modified — Symbols and figure removed, definition modified.]
3.5
lower limit deviation
lower limit of size minus target size (3.6)
Note 1 to entry: Lower limit deviation is a signed value and may be negative, zero or positive.
[SOURCE: ISO 286-1:2010, 3.2.5.2, modified — Symbols removed and definition modified.]
3.6
target size
reference size used in design and in practice in order to indicate the size desired and to which the
deviations, which would ideally be zero, are to be related
[SOURCE: ISO 6707-1:2020, 3.7.2.12, modified — Note 1 to entry removed.]
4 General
4.1 Generality
4.1.1 A limit deviation shall be indicated on a construction document only when there is a functional
requirement to control position, dimension, orientation or form.
4.1.2 Target size shall be the only reference to limit deviation in construction documents.
NOTE The term “deviation” is defined in relation to “nominal size” in ISO 286-1. However, this term is
relevant to “desired value”, associated with the term “target size” in ISO 6707-1, which specifies a vocabulary for
the construction industry.
4.2 Application
Indication of limit deviations shall be applied using the following methods:
a) dimensions on construction drawings or figures within notes;
b) property items within data templates.
4.3 Designations of deviation types
An indication of limit deviations should clarify its type requirements with a designation, when
applicable. Designations of popular deviation types may follow Table 1 or the conventions of the
manufacturing industry.
Table 1 — Designations of popular deviation types
Deviation type Designation
Length deviation LD
Angular deviation AD
Profile deviation of a line PL
Straightness deviation of a line SL
TTabablele 1 1 ((ccoonnttiinnueuedd))
Deviation type Designation
Shape deviation of a surface SS
Flatness deviation of a surface FS
Skewness SK
Position deviation of a point PP
Position deviation of a line PL
Verticality deviation VD
Horizontality deviation HD
NOTE Deviation types listed in Table 1 are defined in ISO 6707-1 and the sequence of the items is the same as
that in ISO 6707-1.
5 Indication of limit deviations
5.1 As dimensions on construction drawings or figures within notes
5.1.1 A limit deviation shall be indicated numerically and be placed with, or adjacent to, the size
concerned in dimensions on construction drawings. A single reference within notes in the space for
text in accordance with IS
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