ISO 3864-3:2024

International
Standard
ISO 3864-3
Third edition
Graphical symbols — Safety colours
2024-05
and safety signs —
Part 3:
Design principles for graphical
symbols for use in safety signs
Symboles graphiques — Couleurs de sécurité et signaux de
sécurité —
Partie 3: Principes de conception pour les symboles graphiques
utilisés dans les signaux de sécurité
Reference number
© ISO 2024
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Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Designing graphical symbols for use in safety signs. 2
5 Review of existing International Standards . 2
6 Assignment of meaning, function, image content and hazard to the safety sign . 2
7 Design criteria . 3
7.1 Geometric shapes and colours of safety signs .3
7.2 Size and position of the graphical symbol .3
7.3 Layout of templates .6
7.4 Exclusion zone . .7
7.4.1 General .7
7.4.2 Prohibition signs .7
7.4.3 Mandatory action signs .8
7.4.4 Warning signs .8
7.4.5 Safe condition signs and fire equipment signs .9
7.5 Line width .9
7.6 Consistency within a family of graphical symbols .11
7.7 Determinants . 12
7.8 Combination of graphical symbols or graphical symbol elements . 13
7.9 Use of arrows in graphical symbols . .14
7.10 Characters.14
Annex A (informative) Additional design guidelines .15
Bibliography .26

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 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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 Technical Committee ISO/TC 145, Graphical symbols, Subcommittee SC 2,
Safety identification, signs, shapes, symbols and colours.
This third edition cancels and replaces the second edition (ISO 3864-3:2012), which has been technically
revised.
The main changes are as follows:
— references have been added in the Introduction to the list of translations of referents and to the ISO
Online Browsing Platform;
— normative references have been updated;
— exclusion zone for warning signs in 7.4.4 has been clarified.
A list of all parts in the ISO 3864 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.

iv
Introduction
Graphical symbols in safety signs are used for a wide range of purposes. There is a need to standardize the
principles for creating these graphical symbols to ensure visual clarity, to maintain consistency and thereby
to improve recognition and comprehension. The principles set out in this document specify the design
criteria by which graphical symbols are judged for standardization and publication in ISO 7010.
Graphical symbols used in safety signs are not always intuitively understood. Often training can be necessary
to inform people about the meaning of a graphical symbol. Such training can take place by including the
meaning of a graphical symbol in operation manuals, company bulletins and training programme materials,
as well as by using supplementary text with the safety sign.
NOTE 1 Information on procedures, criteria of acceptability, safety sign templates and application of safety signs,
as well as translations of the referents, can be found at https://www.iso.org/tc145/sc2.
NOTE 2 All safety signs are available on the ISO Online Browsing Platform at https://www.iso.org/obp.

v
International Standard ISO 3864-3:2024(en)
Graphical symbols — Safety colours and safety signs —
Part 3:
Design principles for graphical symbols for use in safety signs
IMPORTANT — The colours represented in the electronic file of this document can be neither viewed
on screen nor printed as true representations. For the purposes of colour matching see ISO 3864-4,
which provides colorimetric and photometric properties together with, as a guideline, references
from colour order systems.
1 Scope
This document provides principles, criteria and guidance for the design of graphical symbols for use in
safety signs as defined in ISO 3864-1, and for the safety sign element of product safety labels as defined in
ISO 3864-2.
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 3864-1:2011, Graphical symbols — Safety colours and safety signs — Part 1: Design principles for safety
signs and safety markings
ISO 3864-4, Graphical symbols — Safety colours and safety signs — Part 4: Colorimetric and photometric
properties of safety sign materials
ISO 7010, Graphical symbols — Safety colours and safety signs — Registered safety signs
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
determinant
graphical symbol used as a common element within a series of graphical symbols
EXAMPLE The fire determinant, when used with the graphical symbol for a hose reel, conveys the meaning “fire
hose reel”; see Figure 17.
4 Designing graphical symbols for use in safety signs
Before designing a graphical symbol the designer shall:
— develop a clear and unambiguous description of the hazard that the graphical symbol is intended to
address;
— confirm that a new graphical symbol for use in a safety sign is required (i.e. confirm that a suitable
graphical symbol does not already exist; see Clause 5);
— identify the safety message that the safety sign is intended to convey;
— define the characteristics of the target group, including their general skill and ability to understand the
information that the particular safety sign is intended to convey, and design the graphical symbol for
that group;
— assign a meaning and function to the safety sign in accordance with Clause 6;
— identify the type of the safety sign required in accordance with 7.1.
Consideration should be given as to the types of safety sign for which the graphical symbol can be appropriate
and to the design implications such multiple applicability can have. For example, a graphical symbol for use
in a mandatory action sign can be adversely affected by the diagonal bar of a prohibition sign. Also, the
restricted space within the triangle of a warning sign can adversely affect the graphical symbol originally
designed for a prohibition sign.
During the creation process, the designer shall follow the criteria given in Clause 7.
Designers are strongly recommended to use the guidelines set out in Annex A.
5 Review of existing International Standards
The designer shall determine:
— whether a safety sign incorporating a graphical symbol conveying the required meaning is specified in
ISO 7010;
— in cases where a safety sign incorporating a graphical symbol conveying the required meaning is not
specified in ISO 7010, whether there is a registered graphical symbol conveying the required meaning;
— whether registered graphical symbols with similar meanings can be adapted or combined to form the
graphical symbol for the new safety sign;
— whether there are standardi
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