EN ISO 9241-151:2008

Ergonomics of human-system interaction - Part 151: Guidance on World Wide Web user interfaces (ISO 9241-151:2008)

ISO 9241-151:2008 provides guidance on the human-centred design of software Web user interfaces with the aim of increasing usability. Web user interfaces address either all Internet users or closed user groups such as the members of an organization, customers and/or suppliers of a company or other specific communities of users.
The recommendations given in this part of ISO 9241:2008 focus on the following aspects of the design of Web user interfaces: high-level design decisions and design strategy; content design; navigation and search; content presentation.
The user interfaces of different types of user agents such as Web browsers or additional tools such as Web authoring tools are not directly addressed in this part of ISO 9241:2008 (although some of its guidance could apply to these systems as well).
Web user interfaces are presented on a personal computer system, mobile system or some other type of network‑connected device. While the recommendations given in this part of ISO 9241:2008 apply to a wide range of available front‑end technologies, the design of mobile Web interfaces or smart devices could require additional guidance not within its scope; neither does it provide detailed guidance on technical implementation nor on issues of aesthetic or artistic design.

Ergonomie der Mensch-System-Interaktion - Teil 151: Leitlinien zur Gestaltung von Benutzungsschnittstellen für das World Wide Web (ISO 9241-151:2008)

Dieser Teil von ISO 9241 enthält Anleitungen zur benutzerorientierten Gestaltung von Software-Benutzungs¬schnittstellen für Web-Anwendungen mit dem Ziel der Verbesserung der Gebrauchstauglichkeit. Web-Benutzungsschnittstellen richten sich entweder an alle Internetnutzer oder geschlossene Benutzer¬gruppen, wie z. B. die Mitglieder einer Organisation, Kunden und/oder Lieferanten eines Unternehmens oder andere spezifische Nutzergemeinschaften.
Die Empfehlungen in diesem Teil von ISO 9241 konzentrieren sich auf folgende Aspekte der Gestaltung von Web-Benutzungsschnittstellen:
   grundlegende Gestaltungsentscheidungen und -strategien;
   Gestaltung des Inhaltes;
   Navigation und Suche;
   Darstellung des Inhaltes.
Die Benutzungsschnittstellen bestimmter Benutzeragenten (wie Web-Browser) oder zusätzlicher Tools, wie z. B. Webautorentools werden nicht direkt in diesem Teil von ISO 9241 angesprochen, obwohl einige Richt¬linien auch für diese Systeme gelten könnten.
Web-Benutzungsschnittstellen werden auf einem PC-System, einem mobilen System oder anderen vernetz¬ten Geräten dargestellt. Während die in diesem Teil von ISO 9241 gegebenen Empfehlungen für eine große Auswahl zur Verfügung stehender Front-End-Technologien gelten, könnte die Gestaltung von mobilen Web-Schnittstellen oder von mobilen Endgeräten, sog. „Smart Devices“, unter Umständen zusätzliche Richtlinien erfordern, die genauso wenig im Anwendungsbereich liegen wie weiter führende Hilfestellung bei der technischen Umsetzung oder zu Fragen der ästhetischen bzw. künstlerischen Gestaltung.

Ergonomie de l'interaction homme-système - Partie 151: Lignes directrices relatives aux interfaces utilisateurs Web (ISO 9241-151:2008)

L'ISO 9241-151:2008 fournit des lignes directrices relatives à la conception centrée sur l'utilisateur des interfaces logicielles utilisateurs pour les applications Internet (en abrégé, les interfaces utilisateurs Web), en vue d'augmenter leur utilisabilité. Les interfaces utilisateurs Web s'adressent soit à l'ensemble des utilisateurs de l'Internet, soit à des groupes restreints d'utilisateurs, tels que les membres d'une organisation, les clients et/ou les fournisseurs d'une société ou d'autres groupes spécifiques d'utilisateurs.
Les recommandations données dans l'ISO 9241-151:2008 se concentrent sur les aspects suivants de la conception des interfaces utilisateurs Web: les décisions de conception fonctionnelle et la stratégie de conception, la conception du contenu, la navigation et la recherche, et la présentation du contenu.
L'interface utilisateur des différents types d'agents utilisateurs, tels que les navigateurs Internet, ou d'autres outils, tels que les systèmes de développement de contenu Internet, n'entrent pas dans le domaine d'application de l'ISO 9241-151:2008 (bien que certaines lignes directrices puissent également s'appliquer à ces systèmes).
Les interfaces utilisateurs Web peuvent s'afficher sur un ordinateur personnel, sur un équipement portable ou sur tout autre dispositif connecté à un réseau. Bien que les recommandations fournies par l'ISO 9241-151:2008 s'appliquent à une gamme étendue de technologies existantes, la conception des interfaces Web mobiles ou des dispositifs intelligents peut nécessiter des lignes directrices supplémentaires et n'entre pas dans le domaine d'application de l'ISO 9241-151:2008, qui ne fournit pas, non plus, des recommandations détaillées sur la mise en œuvre technique ou sur les aspects relatifs à la conception artistique ou esthétique.

Ergonomija medsebojnega vpliva človek-sistem - 151. del: Smernice za oblikovanje uporabniških vmesnikov za svetovni splet (World Wide Web) (ISO 9241-151:2008)

General Information

• Status: Published
• Publication Date: 14-May-2008
• Withdrawal Date: 29-Nov-2008
• ICS: 13.180 - Ergonomics
• ICS: 35.240.99 - IT applications in other fields
• Technical Committee: CEN/TC 122 - Ergonomics
• Drafting Committee: CEN/TC 122/WG 5 - Ergonomics of human-computer interaction
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 15-May-2008
• Completion Date: 15-May-2008
• Ref Project: SIST EN ISO 9241-151:2008 - Ergonomics of human-system interaction - Part 151: Guidance on World Wide Web user interfaces (ISO 9241-151:2008)

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2008
(UJRQRPLMDPHGVHERMQHJDYSOLYDþORYHNVLVWHPGHO6PHUQLFH]D
REOLNRYDQMHXSRUDEQLãNLKYPHVQLNRY]DVYHWRYQLVSOHW:RUOG:LGH:HE,62

Ergonomics of human-system interaction - Part 151: Guidance on World Wide Web user
interfaces (ISO 9241-151:2008)
Ergonomie der Mensch-System-Interaktion - Teil 151: Leitlinien zur Gestaltung von
Benutzungsschnittstellen für das World Wide Web (ISO 9241-151:2008)
Ergonomie de l'interaction homme-système - Partie 151: Lignes directrices relatives aux
interfaces utilisateurs Web (ISO 9241-151:2008)
Ta slovenski standard je istoveten z: EN ISO 9241-151:2008
ICS:
13.180 Ergonomija Ergonomics
35.240.99 8SRUDEQLãNHUHãLWYH,7QD IT applications in other fields
GUXJLKSRGURþMLK
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 9241-151
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2008
ICS 13.180; 35.240.99
English Version
Ergonomics of human-system interaction - Part 151: Guidance
on World Wide Web user interfaces (ISO 9241-151:2008)
Ergonomie de l'interaction homme-système - Partie 151: Ergonomie der Mensch-System-Interaktion - Teil 151:
Lignes directrices relatives aux interfaces utilisateurs Web Leitlinien zur Gestaltung von Benutzungsschnittstellen für
(ISO 9241-151:2008) das World Wide Web (ISO 9241-151:2008)
This European Standard was approved by CEN on 8 May 2008.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9241-151:2008: E
worldwide for CEN national Members.

Contents Page
Foreword.3

Foreword
This document (EN ISO 9241-151:2008) has been prepared by Technical Committee ISO/TC 159
"Ergonomics" in collaboration with Technical Committee CEN/TC 122 “Ergonomics” the secretariat of which is
held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by November 2008, and conflicting national standards shall be withdrawn
at the latest by November 2008.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 9241-151:2008 has been approved by CEN as a EN ISO 9241-151:2008 without any
modification.
INTERNATIONAL ISO
STANDARD 9241-151
First edition
2008-05-15
Ergonomics of human-system
interaction —
Part 151:
Guidance on World Wide Web user
interfaces
Ergonomie de l'interaction homme-système —
Partie 151: Lignes directrices relatives aux interfaces utilisateurs Web

Reference number
ISO 9241-151:2008(E)
©
ISO 2008
ISO 9241-151:2008(E)
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ii © ISO 2008 – All rights reserved

ISO 9241-151:2008(E)
Contents Page
Foreword. iv
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Application . 6
5 A reference model for human-centred design of World Wide Web user interfaces . 7
6 High-level design decisions and design strategy . 8
7 Content design. 10
8 Navigation and search. 16
9 Content presentation. 26
10 General design aspects . 33
Annex A (informative) Overview of the ISO 9241 series. 36
Annex B (informative) Sample procedure for assessing applicability and conformance . 40
Bibliography . 49

ISO 9241-151:2008(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 9241-151 was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 4,
Ergonomics of human-system interaction.
ISO 9241 consists of the following parts, under the general title Ergonomic requirements for office work with
visual display terminals (VDTs):
⎯ Part 1: General introduction
⎯ Part 2: Guidance on task requirements
⎯ Part 3: Visual display requirements
⎯ Part 4: Keyboard requirements
⎯ Part 5: Workstation layout and postural requirements
⎯ Part 6: Guidance on the work environment
⎯ Part 7: Requirements for display with reflections
⎯ Part 8: Requirements for displayed colours
⎯ Part 9: Requirements for non-keyboard input devices
⎯ Part 11: Guidance on usability
⎯ Part 12: Presentation of information
⎯ Part 13: User guidance
⎯ Part 14: Menu dialogues
⎯ Part 15: Command dialogues
⎯ Part 16: Direct manipulation dialogues
⎯ Part 17: Form filling dialogues
iv © ISO 2008 – All rights reserved

ISO 9241-151:2008(E)
Guidance on software individualization is to form the subject of a future part 129.
ISO 9241 also consists of the following parts, under the general title Ergonomics of human-system interaction:
⎯ Part 20: Accessibility guidelines for information/communication technology (ICT) equipment and services
⎯ Part 110: Dialogue principles
⎯ Part 151: Guidance on World Wide Web user interfaces
⎯ Part 171: Guidance on software accessibility
⎯ Part 300: Introduction to electronic visual display requirements
⎯ Part 302: Terminology for electronic visual displays
⎯ Part 303: Requirements for electronic visual displays
⎯ Part 304: User performance test methods
⎯ Part 305: Optical laboratory test methods for electronic visual displays
⎯ Part 306: Field assessment methods for electronic visual displays
⎯ Part 307: Analysis and compliance test methods for electronic visual displays
⎯ Part 308: Surface-conduction electron-emitter displays (SED) [Technical Report]
⎯ Part 309: Organic light-emitting diode (OLED) displays [Technical Report]
⎯ Part 400: Principles and requirements for physical input devices
⎯ Part 410: Design criteria for physical input devices
⎯ Part 920: Guidance on tactile and haptic interactions
Framework for tactile and haptic interaction is to form the subject of a future part 910.
ISO 9241-151:2008(E)
Introduction
It is widely accepted that usability is a key factor in successful website design but until now there has been no
internationally agreed standard that specifically addressed the usability of World Wide Web (WWW or Web)
user interfaces.
World Wide Web user interfaces pose particular usability problems:
⎯ their users are diverse in knowledge, capabilities, language and other factors — for example, a World
Wide Web user interface that works well for subject-matter experts may be sub-optimal for ordinary users;
⎯ users’ goals vary considerably — for example, a site optimized for one set of tasks (such as e-commerce
transactions) could be sub-optimal for users whose tasks are different (such as information gathering);
⎯ different Web browsers or user agents often render Web content in different ways — for example, the
layout of individual pages can change, sometimes quite dramatically.
Users of the World Wide Web will have experienced the problems of inconsistency between websites and
often even within the same website. For example, something as straightforward as a link may be denoted by
underlining on one page, by a mouse-over on a second page and by nothing at all on a third page.
A number of guidelines for good practice exist, many on the Web itself, but these guidelines sometimes
conflict and can also be difficult to put into practice. While not addressing Web user interfaces specifically, a
number of International Standards are available that provide useful guidance on usability and the design of
user interfaces: ISO 9241-11 to ISO 9241-17 and ISO 9241-110 provide ergonomic guidance on the design of
software user interfaces in general, ISO 13407 on achieving usability by incorporating user-centred design
activities throughout the life cycle of interactive computer-based systems, and the ISO 14915 series of
standards on the design of multimedia and hypermedia aspects of user interfaces.
The recommendations and guidelines provided in this part of ISO 9241 apply primarily to the design of the
content of a website or, more generally, a Web application, the user's navigation and interaction, as well as
the presentation of the content. The user interface of different types of user agents (such as Web browsers) or
additional tools such as Web authoring tools ar
...