Ergonomics of human-system interaction - Part 304: User performance test methods for electronic visual displays (ISO 9241-304:2008)

This part of ISO 9241 provides guidance for assessing the visual ergonomics of display technologies with user performance test methods (as opposed to the optical test methods given in ISO 9241-305). Its use will help to ensure that, for a given context of use, a display meets minimum visual ergonomics requirements. It covers only visual attributes and does not address the ergonomics or usability of the whole product that houses a visual display. The general principles laid down by this part of ISO 9241 apply to any colour or monochrome visual display attached to a system with which human beings interact. This includes, but is not limited to, visual displays used with desktop and portable computers, those used on mobile devices such as mobile telephones, digital cameras and personal digital assistants, and status displays used on consumer electronics equipment such as printers, in-car navigation systems and microwave ovens. It extends the basic idea of the visual performance and comfort test specified in ISO 9241-3:1992/Amd.1:2000 to the use of the performance and judgment of the display end users themselves for evaluating the quality of a display, and includes a more diverse range of technologies, users, tasks and environments. Because of this diversity, it is not feasible for this part of ISO 9241 to stipulate a single, generic test method that can be used with all display technologies. Instead, the basic principles for generating a test method are given. This method will be valid for evaluating specific displays in specific contexts of use: the method generated according to Clause 8 is applicable only to tasks involving the handling and processing of text. No other examples are given. An essential property of the process is that it permits the verification of the usability of a visual display for a representative task, performed by representative users, taking their performance and judgment as measured quality values. It does not, however, permit the measurement of specific perceptual attributes such as luminance contrast or display flicker in isolation. The main users of this part of ISO 9241 will be those who procure displays or who need to measure display performance during product development. Its application assumes a background in behavioural science.

Ergonomie der Mensch-System-Interaktion - Teil 304: Prüfverfahren zur Benutzerleistung (ISO 9241-304:2008)

Dieser Teil der ISO 9241 bietet einen Leitfaden zur Beurteilung der visuellen Ergonomie von Anzeigetechnolo¬gien unter Anwendung von Verfahren zur Prüfung der Leistungsfähigkeit der Nutzer (im Gegensatz zu den optischen Prüfverfahren in ISO 9241-305). Die Anwendung dieser Norm hilft in einem gegebenen Anwendungskontext sicherzustellen, dass eine Anzeige die Mindestanforderungen an die visuelle Ergonomie erfüllt. Die Norm deckt nur die visuellen Merkmale von Anzeigen ab. Sie bezieht sich nicht auf die Ergonomie oder Gebrauchstauglichkeit des gesamten Produktes, in dem die visuelle Anzeige enthalten ist.
Die in diesem Teil von ISO 9241 festlegten allgemeinen Grundsätze der Norm gelten für jegliche farbige oder einfarbige visuelle Anzeigen, die mit einem System verbunden sind, mit dem Menschen interagieren. Darin eingeschlossen, aber nicht auf diese beschränkt, sind: visuelle Anzeigen, die mit ortsfesten oder tragbaren Computern verwendet werden, Anzeigen in mobilen Geräten wie beispielsweise Mobiltelefonen, Digitalkameras und digitalen personenbezogenen Geräten sowie Statusanzeigen in elektronischen Geräten für Verbraucher wie beispielsweise Drucker, Navigationssysteme in Fahrzeugen und Mikrowellengeräten. Dadurch wird der Anwendungsbereich der in ISO 9241 3:1992/Amd.1:2000 festgelegten Prüfung der visuellen Leistung und Beeinträchtigungsfreiheit erweitert, um die Leistung der Endverbraucher selbst und deren Beurteilung der Anzeige zur Bewertung der Qualität der betreffenden Anzeige zu verwenden, um einen mannigfaltigeren Bereich von Technologien, Benutzern, Aufgaben und Umgebungen abzudecken.
Aufgrund dieser Mannigfaltigkeit ist es unmöglich, in diesem Teil von ISO 9241 ein einziges, generelles Prüfverfahren festzulegen, das auf sämtliche Anzeigetechnologien anwendbar ist.

Ergonomie de l'interaction homme-système - Partie 304: Méthodes d'essai de la performance de l'utilisateur pour écrans de visualisation électroniques (ISO 9241-304:2008)

L'ISO 9241-304:2008 fournit des lignes directrices relatives à l'évaluation de l'ergonomie visuelle des technologies d'affichage, au moyen de méthodes d'essai de la performance humaine (par opposition aux méthodes d'essai optique données dans l'ISO 9241-305). Son utilisation aidera à s'assurer que, pour un contexte d'utilisation donné, un affichage satisfait aux exigences ergonomiques visuelles minimales. Elle ne concerne que les attributs visuels, et ne couvre ni l'ergonomie ni l'utilisabilité du produit entier qui intègre l'écran de visualisation.
Les principaux utilisateurs de l'ISO 9241-304:2008 seront des personnes qui achètent des écrans de visualisation ou qui doivent mesurer la performance de l'affichage pendant l'élaboration d'un produit. Son application suppose une base de connaissance en science comportementale.

Ergonomija medsebojnega vpliva človek-sistem - 304. del: Preskusni postopki za določanje uporabnikove sposobnosti delovanja (ISO 9241-304:2008)

General Information

Status
Published
Publication Date
22-Dec-2008
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
08-Dec-2008
Due Date
12-Feb-2009
Completion Date
23-Dec-2008

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SLOVENSKI STANDARD
SIST EN ISO 9241-304:2009
01-februar-2009
(UJRQRPLMDPHGVHERMQHJDYSOLYDþORYHNVLVWHPGHO3UHVNXVQLSRVWRSNL]D
GRORþDQMHXSRUDEQLNRYHVSRVREQRVWLGHORYDQMD ,62
Ergonomics of human-system interaction - Part 304: User performance test methods for
electronic visual displays (ISO 9241-304:2008)
Ergonomie der Mensch-System-Interaktion - Teil 304: Prüfverfahren zur
Benutzerleistung (ISO 9241-304:2008)
Ergonomie de l'interaction homme-système - Partie 304: Méthodes d'essai de la
performance de l'utilisateur pour écrans de visualisation électroniques (ISO 9241-
304:2008)
Ta slovenski standard je istoveten z: EN ISO 9241-304:2008
ICS:
13.180 Ergonomija Ergonomics
35.180 Terminalska in druga IT Terminal and other
periferna oprema IT peripheral equipment
SIST EN ISO 9241-304:2009 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 9241-304:2009

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SIST EN ISO 9241-304:2009
EUROPEAN STANDARD
EN ISO 9241-304
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2008
ICS 13.180; 35.180

English Version
Ergonomics of human-system interaction - Part 304: User
performance test methods for electronic visual displays (ISO
9241-304:2008)
Ergonomie de l'interaction homme-système - Partie 304: Ergonomie der Mensch-System-Interaktion - Teil 304:
Méthodes d'essai de la performance de l'utilisateur pour Prüfverfahren zur Benutzerleistung (ISO 9241-304:2008)
écrans de visualisation électroniques (ISO 9241-304:2008)
This European Standard was approved by CEN on 11 July 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 9241-304:2008: E
worldwide for CEN national Members.

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SIST EN ISO 9241-304:2009
EN ISO 9241-304:2008 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 9241-304:2009
EN ISO 9241-304:2008 (E)
Foreword
This document (EN ISO 9241-304:2008) 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 May 2009, and conflicting national standards shall be withdrawn at the
latest by May 2009.
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 9241-304:2008 has been approved by CEN as a EN ISO 9241-304:2008 without any
modification.

3

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SIST EN ISO 9241-304:2009

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SIST EN ISO 9241-304:2009

INTERNATIONAL ISO
STANDARD 9241-304
First edition
2008-11-15


Ergonomics of human-system
interaction —
Part 304:
User performance test methods for
electronic visual displays
Ergonomie de l'interaction homme-système
Partie 304: Méthodes d'essai de la performance de l'utilisateur pour
écrans de visualisation électroniques





Reference number
ISO 9241-304:2008(E)
©
ISO 2008

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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
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ii © ISO 2008 – All rights reserved

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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
Contents Page
Foreword .iv
Introduction.vi
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
4 Guiding principles .2
5 Conformance .2
6 Specifying the visual ergonomics test objectives .3
6.1 General .3
6.2 Criterion description .3
6.3 Measuring method.3
6.4 Performance criteria.3
7 Defining the test procedure.4
7.1 General .4
7.2 Alphanumeric and non-alphanumeric text .4
8 Visual performance and comfort test — Carrying out the test and analysing the data.5
8.1 General .5
8.2 Purpose .5
8.3 Overview.5
8.4 Test participants.6
8.5 The displays.6
8.6 Test setup.6
8.7 Dependent measures .11
8.8 Statistical treatment of results.12
8.9 Critical values for Barnard's U test.14
Annex A (informative) Overview of the ISO 9241 series .16
Bibliography.20

© ISO 2008 – All rights reserved iii

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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(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 9241-304 was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 4,
Ergonomics of human-system interaction.
This first edition of ISO 9241-304, together with ISO 9241-302:2008, ISO 9241-303:2008, ISO 9241-305:2008
and ISO 9241-307:2008, cancels and replaces ISO 9241-3:1992, of which it constitutes a technical revision. It
also incorporates the Amendment ISO 9241-3:1992/Amd.1:2000, replacing that Amendment's test method
with the one specified in Clause 8.
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 4: Keyboard requirements
⎯ Part 5: Workstation layout and postural requirements
⎯ Part 6: Guidance on the work environment
⎯ 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

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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
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 for electronic visual displays
⎯ 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
For the other parts under preparation, see Annex A.
© ISO 2008 – All rights reserved v

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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
Introduction
ISO 9241 was originally developed as a seventeen-part International Standard on the ergonomics
requirements for office work with visual display terminals. As part of the standards review process, a major
restructuring of ISO 9241 was agreed to broaden its scope, to incorporate other relevant standards and to
make it more usable. The general title of the revised ISO 9241, “Ergonomics of human-system interaction”,
reflects these changes and aligns the standard with the overall title and scope of Technical Committee
ISO/TC 159, Subcommittee SC 4. The revised multipart standard is structured as series of standards
numbered in the “hundreds”: the 100 series deals with software interfaces, the 200 series with human centred
design, the 300 series with visual displays, the 400 series with physical input devices, and so on.
See Annex A for an overview of the entire ISO 9241 series.
ISO 9241-3:1992, Annex C, offered users a provisional alternative method for testing the visual quality of a
display, intended for novel display technologies for which no optical test method was available. The
Amendment ISO 9241-3:1992/Amd.1:2000 replaced this test method and made the previously informative
Annex C normative. ISO 9241-7:1998, ISO 9241-8:1997 and ISO 13406-2:2001 (all three of which have since
been cancelled and replaced by other parts of the ISO 9241 “300” subseries) referred to that Amendment as
providing an alternative user performance test method.
This part of ISO 9421 not only incorporates the Amendment, but extends its basis to provide guidance on the
general process of assessing the visual ergonomics of displays in a specific context of use by means of a user
performance test method. The test method specified in this part of ISO 9241 is applicable only to user tasks
involving the handling and processing of text. However, it is expected that test procedures will also be
developed for using maps and for handling and interpreting photographs and moving images, with these then
being incorporated into a future edition.
The structure of this part of ISO 9241 is an exception in the ISO 9241 “300” subseries in that it establishes the
conformance of a visual display used for text rendition according to its own user performance test method,
instead of by means of a compliance route given in ISO 9241-307 (in which no compliance route relevant to
this part of ISO 9241 is provided).

vi © ISO 2008 – All rights reserved

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SIST EN ISO 9241-304:2009
INTERNATIONAL STANDARD ISO 9241-304:2008(E)

Ergonomics of human-system interaction —
Part 304:
User performance test methods for electronic visual displays
1 Scope
This part of ISO 9241 provides guidance for assessing the visual ergonomics of display technologies with user
performance test methods (as opposed to the optical test methods given in ISO 9241-305). Its use will help to
ensure that, for a given context of use, a display meets minimum visual ergonomics requirements. It covers
only visual attributes and does not address the ergonomics or usability of the whole product that houses a
visual display.
The general principles laid down by this part of ISO 9241 apply to any colour or monochrome visual display
attached to a system with which human beings interact. This includes, but is not limited to, visual displays
used with desktop and portable computers, those used on mobile devices such as mobile telephones, digital
cameras and personal digital assistants, and status displays used on consumer electronics equipment such
as printers, in-car navigation systems and microwave ovens. It extends the basic idea of the visual
performance and comfort test specified in ISO 9241-3:1992/Amd.1:2000 to the use of the performance and
judgment of the display end users themselves for evaluating the quality of a display, and includes a more
diverse range of technologies, users, tasks and environments.
Because of this diversity, it is not feasible for this part of ISO 9241 to stipulate a single, generic test method
that can be used with all display technologies. Instead, the basic principles for generating a test method are
given. This method will be valid for evaluating specific displays in specific contexts of use: the method
generated according to Clause 8 is applicable only to tasks involving the handling and processing of text. No
other examples are given. An essential property of the process is that it permits the verification of the usability
of a visual display for a representative task, performed by representative users, taking their performance and
judgment as measured quality values. It does not, however, permit the measurement of specific perceptual
attributes such as luminance contrast or display flicker in isolation.
The main users of this part of ISO 9241 will be those who procure displays or who need to measure display
performance during product development. Its application assumes a background in behavioural science.
2 Normative references
The following referenced documents are indispensable for the application 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 9241-5, Ergonomic requirements for office work with visual display terminals (VDTs) — Part 5:
Workstation layout and postural requirements
ISO 9241-6, Ergonomic requirements for office work with visual display terminals (VDTs) — Part 6: Guidance
on the work environment
ISO 9241-302, Ergonomics of human-system interaction — Part 302: Terminology for electronic visual
displays
© ISO 2008 – All rights reserved 1

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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
ISO 9241-303:2008, Ergonomics of human-system interaction — Part 303: Requirements for electronic visual
displays
ISO/IEC 8859 (all parts), Information technology — 8-bit single-byte coded graphic character sets
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9241-302 apply.
4 Guiding principles
The guiding principles of this part of ISO 9241 are that visual displays should help people carry out their tasks
effectively and efficiently, and that displays should be satisfying to use and not in any way be harmful to their
users' health.
Formal optical test methods as specified in ISO 9241-305 might not be available to support the procurement
of newer display technologies. In such cases, requiring manufacturers to demonstrate evidence of the
usability of their displays provides the most effective route for ensuring good ergonomics quality. This is the
approach taken by this part of ISO 9241.
It sets out four steps for generating test methods that can be used to measure the ergonomics visual quality of
visual displays:
a) specify the visual ergonomic test objectives (see Clause 6);
b) define the test procedure (see Clause 7);
c) carry out the test (see Clause 8);
d) analyse the data (see Clause 8).
5 Conformance
Whereas ISO 9241-303 and ISO 9241-305 refer to the compliance routes defined in ISO 9241-307 to
establish the conformance of a visual display, this part of ISO 9241 itself specifies a test method for
establishing such conformance.
If the test display is compared to a benchmark display and the test procedure is based on either alphanumeric
or non-alphanumeric text, conformance is achieved when both
⎯ the search speed for the test display is not statistically significantly lower than the search speed obtained
with the benchmark display, and
⎯ the perceived quality, as measured by its visual comfort rating, of the test display is not statistically
significantly lower than that of the benchmark display.
The procedure used for determining search speed and perceived quality shall be in accordance with Clause 8.
2 © ISO 2008 – All rights reserved

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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
6 Specifying the visual ergonomics test objectives
6.1 General
Visual ergonomics can be measured like any other engineering attribute. Although the data from user
performance tests are derived from objective and subjective measures of human performance, this does not
mean that the data are simply personal opinions. A good test design will generate data that are objective and
unbiased. Useful information on many practical aspects of test design in general is given in ISO 20282;
ISO 20282-1, in particular, provides valuable background information in this area.
Testing only makes sense if the test results are compared with criteria that define a display as acceptable or
unacceptable. The aim of this step is to define those criteria for the display to be tested.
6.2 Criterion description
The criterion description defines the context of the measurements and the performance characteristics that
will be measured. In most cases — when, for instance, a novel display technology is used in a visual display
that helps perform an existing task (such as word processing in an office) — the visual quality of the test
display is assessed against that of a benchmark display known to meet or exceed the requirements of
ISO 9241-303, using a measuring method according to ISO 9241-305 and a conformance method according
to ISO 9241-307.
EXAMPLE A test of a display that will be used for in-car navigation might use as the criterion: “Ease of reading
information from the display when it is used by experienced drivers in bright ambient lighting”.
6.3 Measuring method
The measuring method describes how the criterion will be measured, i.e. the scale that will be used for the
measurement and how the values will be derived.
As an example, in ISO 9241-11, three separate measures are taken:
⎯ effectiveness (the accuracy and completeness with which customers achieve specified goals);
⎯ efficiency (the accuracy and completeness of goals achieved in relation to resources);
⎯ satisfaction (freedom from discomfort, and positive attitudes towards the use of the visual display).
It needs be realized that these three measures from ISO 9241-11 are context-dependent; this means that, for
example, the effectiveness of a mobile phone display could be low — even very low compared to that of a
desktop display — yet entirely satisfactory in the context of mobile phone use.
EXAMPLE A test of a display used on a mobile phone measures the accuracy with which a participant can
distinguish different colours (effectiveness), the speed with which a participant can read text on the display (efficiency) as
well as the participant's overall attitude towards the display's image quality (satisfaction).
6.4 Performance criteria
If the test display is compared to a benchmark display, the performance criterion is normally that the test
display have at least the same visual quality as the benchmark one. But in other cases, making a decision on
the value that is acceptable can require some market analysis. Useful questions to ask at this stage include
the following.
⎯ Is there an earlier version of the tested display that is relevant in this context? If so, how is its visual
quality rated?
⎯ How do competitors displays perform?
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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
These values provide the engineer with a lower limit to place on the performance of the display. Human
factors specialists recommend that the response range be considered as a continuum ranging from
“Unacceptable”, through a “Minimum” range into a “Target” range, and finally into an “Exceeds” range, as
follows.
a) Unacceptable
If the display performs within this range, it cannot be released.
b) Minimum
If the display performs within this range, it is barely acceptable. Management must weigh the benefits of
releasing a barely adequate display now, versus waiting for the usability defects to be fixed.
c) Target
If the display performs within this range, it can be released. This is the performance range thought to be
necessary to succeed.
d) Exceeds
If the display performs within this range, it could be that the development team have put too much effort
into the design of the display and/or developed a product surpassing requirements.
This approach makes it unlikely that the development team will either under- or over-engineer the display.
7 Defining the test procedure
7.1 General
The test procedure shall be oriented towards a task carried out with the help of a visual display: a user
performance test method as defined in this part of ISO 9241 relies on a user behaving as when performing a
typical task of this kind.
7.2 Alphanumeric and non-alphanumeric text
The visual performance and comfort test specified in Clause 8 may be used to establish the conformance of a
visual display to a certain quality, according to user performance, applicable to tasks involving the handling
and processing of text. Its test procedure is suitable for such tasks, typical of an office environment. Test
methods for other types of tasks, with their appropriate devices, remain to be developed.
NOTE 1 So far, no test procedure for using maps has been developed.
NOTE 2 So far, no test procedure for handling and interpreting photographs has been developed.
NOTE 3 So far, no test procedure for handling and interpreting moving images has been developed.
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SIST EN ISO 9241-304:2009
ISO 9241-304:2008(E)
8 Visual performance and comfort test — Carrying out the test and analysing
the data
8.1 General
This clause specifies a method that can be used to test the visual quality of electronic visual displays where
the entire set of physical requirements (viz. ISO 9241-303) cannot be applied — for example, in the case of
novel display technologies such as new types of flat panel display (e.g. electroluminescent or field emission
displays). The test consists of a letter search task and an assessment of visual comfort.
The context of use is text processing, such as that which takes place in office work. The combination of test
results will be referred to as the visual quality of the display.
The various stages of the test, such as recruiting participants, running a pilot test and administering the final
test are described (see also ISO/TS 20282-2), as is the analysis of the test data, including application of
statistics.
8.2 Purpose
The method tests displays that cannot otherwise be tested for conformance with ISO 9241. It is not an
alternative test met
...

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