ISO/IEC 24751-3:2008

Information technology - Individualized adaptability and accessibility in e-learning, education and training - Part 3: "Access for all" digital resource description

ISO/IEC 24751-3:2008 provides a common language for describing digital learning resources to facilitate matching of those resources to learners' accessibility needs and preferences (as defined in ISO/IEC 24751-2). This description is one side of a pair of descriptions used in matching user needs and preferences with education delivery (as described in ISO/IEC 24751-1). ISO/IEC 24751-3:2008 discusses the basic principles adhered to in developing this model for describing digital learning resources. It explains: the assumptions made in developing ISO/IEC 24751-3:2008, the notion of an original and adapted resource, the major categories of metadata for original and adapted resources, the notion of an access mode for a resource, what is meant by adaptability, and the importance of interoperability and the role played by consistent implementation in interoperability. It contains the information model for ISO/IEC 24751-3, including the attribute, allowed occurrence and datatype of each element. It defines and describes how the terms in the information model should be used, and explains how ISO/IEC 24751-3:2008 can be extended. It discusses conformance to ISO/IEC 24751-3. Conformance is dependent on the role played by the conformant technology. Conformance requirements for both education delivery applications, resources and metadata authoring tools are explained. ISO/IEC 24751-3:2008 provides a consolidated list of all the terms defined in ISO/IEC 24751-3:2008, sorted in French alphabetical order, the ISO French language equivalent terms and definitions, and the codes representing the gender of the French terms. The vocabulary codes, values and associated rules of application are defined. An informative list of recommended default values for the learner preferences and needs is provided. It lists existing bindings of the IMS Access for All Metadata Specification Version 1 (ACCMD) that serves as the reference specification for ISO/IEC 24751-3:2008. It describes information scenarios for applying ISO/IEC 24751-3:2008 and gives informative implementation examples. Use of ISO/IEC 24751-3:2008 will assist in matching individual learner needs in a computer-mediated learning environment with the necessary user interface and resources needed to meet those needs.

Technologies de l'information — Adaptabilité et accessibilité individualisées en e-apprentissage, en éducation et en formation — Partie 3: Description des ressources numériques relatives à "accès pour tous"

General Information

• Status: Published
• Publication Date: 15-Sep-2008
• ICS: 03.100.30 - Management of human resources
• ICS: 35.240.90 - IT applications in education
• ICS: 35.240.99 - IT applications in other fields
• Technical Committee: ISO/IEC JTC 1/SC 36 - Information technology for learning, education and training
• Drafting Committee: ISO/IEC JTC 1/SC 36/WG 7 - ITLET - Culture, language and individual needs
• Current Stage: 9020 - International Standard under periodical review
• Start Date: 15-Oct-2025
• Completion Date: 15-Oct-2025

Overview

ISO/IEC 24751-3:2008 - titled Information technology - Individualized adaptability and accessibility in e-learning, education and training - Part 3: “Access for all” digital resource description - defines a common metadata language for describing digital learning resources so they can be matched to individual learners’ accessibility needs and preferences. Part 3 supplies the digital resource description (DRD) information model, the vocabulary codes, recommended defaults, conformance rules and implementation examples to support interoperable, automated matching of resources to users in computer-mediated learning environments.

Key topics and requirements

• Accessibility metadata to describe how resources can be perceived, understood and interacted with (sensory modalities, input methods, available adaptations).
• Information model specifying each element’s attributes, allowed occurrence and datatype (the DRD structure).
• Access mode statements and adaptation statements (including “is adaptation” and adaptation coverage/type) to indicate how a resource supports alternate modes (audio, visual, tactile, captions, etc.).
• Adaptability concepts - whether and how a resource can be transformed (text-to-speech, display transformability, control flexibility).
• Vocabulary codes and rules (annexed) to ensure consistent descriptions across systems.
• Conformance requirements tailored to the role of the implementer: education delivery applications, digital resources, and metadata authoring tools.
• Guidance and examples: informative annexes with recommended default values, bindings (e.g., IMS Access for All ACCMD), scenarios and implementation samples.

Applications and practical value

• Enables learning management systems (LMS), content repositories and search engines to automatically discover and deliver resources that match a learner’s personal needs and preferences.
• Helps content authors and metadata specialists create interoperable accessibility metadata that supports personalization and adaptive delivery.
• Assists assistive technology and accessibility tool vendors to integrate resource compatibility information for better user experiences.
• Supports institutions and procurement teams aiming to deliver inclusive e-learning by enabling automated matching rather than manual remediation.

Who should use it

• LMS/platform developers, repository and content-package authors
• Metadata authoring tool vendors and metadata librarians
• Accessibility specialists, instructional designers and assistive technology vendors
• Organizations implementing personalized or adaptive e-learning at scale

Related standards

• ISO/IEC 24751-1: Framework and reference model
• ISO/IEC 24751-2: “Access for all” personal needs and preferences (PNP) - used together with Part 3 for matching
• Complementary guidance: W3C/WAI WCAG for content-level accessibility best practices

Using ISO/IEC 24751-3:2008 helps operationalize “access for all” by standardizing how digital learning resources state their accessibility and adaptability, enabling consistent, interoperable personalization across e-learning ecosystems.

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 24751-3
First edition
2008-10-01
Information technology — Individualized
adaptability and accessibility in
e-learning, education and training —
Part 3:
“Access for all” digital resource
description
Technologies de l'information — Adaptabilité et accessibilité
individualisées en e-apprentissage, en éducation et en formation —
Partie 3: Description des ressources numériques relatives à «accès
pour tous»
Reference number
©
ISO/IEC 2008
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©  ISO/IEC 2008
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ii © ISO/IEC 2008 – All rights reserved

Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
4 Symbols and abbreviations.5
5 Basic Principles.6
5.1 Assumptions.6
5.2 Original and Adapted Resources.6
5.3 Access For All Resource Metadata .7
5.4 Access Mode.7
5.5 Adaptability .8
5.6 The Importance of Interoperability and Consistent Implementation .9
6 Access For All Digital Resource Description (DRD) Information Model .10
6.1 Access For All Digital Resource Description .10
6.2 Access Mode Statement .10
6.3 Is Adaptation.11
6.4 Adaptation Statement .11
7 Attribute Descriptions and Recommended Use.11
8 Extending the Standard .15
9 Conformance .15
Annex A (normative) Consolidated List of Terms and Definitions with Cultural Adaptability:
ISO French Equivalents .16
A.1 Introduction.16
A.2 ISO English and ISO French.16
A.3 Cultural adaptability and quality control.16
A.4 List of Terms in French Alphabetical Order .17
A.5 Organization of Annex A.6, “Consolidated matrix of terms and definitions —
ISO French equivalents” .18
A.6 Consolidated Matrix of ISO/IEC 24751-3 Terms and Definitions in ISO French.19
Annex B (normative) Vocabulary Codes .23
B.1 Access Mode Usage Vocabulary Codes .23
B.2 Display Transformability Vocabulary Codes.23
B.3 Extent Vocabulary Codes .25
Annex C (informative) Recommended Default Values .26
Annex D (informative) Bindings and Implementations .27
Annex E (informative) Scenarios.28
E.1 Scenario 1: Discovery and Retrieval of Alternate Training Content .28
E.2 Scenario 2: Customization of Information about a Prescription.28
E.3 Scenario 3: Extreme Instructional Environments .28
E.4 Scenario 4: Creating a Repository for Federated Searching.29
Annex F (informative) Implementation Example.30
F.1 TILE Low Vision Example.30
F.2 TILE Caption Example.33
Annex G (informative) List of contributors.37
Bibliography.38
© ISO/IEC 2008 – All rights reserved iii

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national 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 and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 24751-3 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 36, Information technology for learning, education, and training.
ISO/IEC 24751 consists of the following parts, under the general title Information technology — Individualized
adaptability and accessibility in e-learning, education and training:
⎯ Part 1: Framework and reference model
⎯ Part 2: “Access for all” personal needs and preferences for digital delivery
⎯ Part 3: “Access for all” digital resource description
Future parts will address non-digital resource description, personal needs and preferences for non-digital
resources, personal needs and preferences for description of events and places, digital description of events
and places, and language accessibility and human interface equivalencies (HIEs) in e-learning applications.
iv © ISO/IEC 2008 – All rights reserved

Introduction
In this part of ISO/IEC 24751, the term disability is defined as a mismatch between the needs of the user and
the resource offered. It is not a personal trait therefore but an artifact of the relationship between the user and
the resource environment or delivery. Accessible systems adjust the user interface of the learning
environment, locate needed resources, evaluate the properties of the available resources to match the needs
and preferences of the user, and deliver to the learner the most accessible content available.
This part of ISO/IEC 24751 defines accessibility metadata that is able to express a resource's ability to match
the needs and preferences of a user, as described by their access for all personal needs and preferences
(PNP), already defined in ISO/IEC 24751-2. This part of ISO/IEC 24751 is intended to benefit anyone
experiencing a mismatch between needs and preferences and education delivered.
For people with disabilities, whose choice of access modalities is restricted, the process of matching a
resource with a user requirement is not a matter of convenience or refinement, but one of utmost importance
in ensuring access. As a result, it is necessary for systems to agree upon well-defined interfaces and usage.
This closely defined approach is taken by this part of ISO/IEC 24751 to support optimum interoperability.
This part of ISO/IEC 24751 is not judgmental but informative. The purpose is to facilitate the discovery and
use of the most appropriate content for each user. Users of alternative access systems need to know whether
a resource is compatible with their required access method, e.g. a user who is blind may need audible access
to a resource as opposed to visual access.
This part of ISO/IEC 24751 does not describe how to create accessible content; other work has been
completed that describes how content and media objects can be made more accessible [see, for example,
W3C/WAI Web Content Accessibility Guidelines (W3C/WAI WCAG) for details].

© ISO/IEC 2008 – All rights reserved v

INTERNATIONAL STANDARD ISO/IEC 24751-3:2008(E)

Information technology — Individualized adaptability and
accessibility in e-learning, education and training —
Part 3:
“Access for all” digital resource description
1 Scope
ISO/IEC 24751 is intended to meet the needs of learners with disabilities and anyone who is disabled by their
context.
This part of ISO/IEC 24751 provides a common language to describe digital learning resources to facilitate
matching of those resources to learners’ accessibility needs and preferences.
Metadata can be used for at least two accessibility-related purposes: to record compliance to an accessibility
specification or standard (e.g. for adherence to legislated procurement policies) and to enable the delivery of
resources that meet a user's needs and preferences. This part of ISO/IEC 24751 addresses the latter purpose.
Metadata to assert compliance to an accessibility specification or standard is not within the scope of this part
of ISO/IEC 24751.
This part of ISO/IEC 24751 is intended to be applied in combination with ISO/IEC 24751-2, which provides a
means to describe how a user desires to access online learning content and related applications. This part of
ISO/IEC 24751 is intended to describe aspects of a computer system (including networked systems) that can
be adjusted to improve accessibility. They are not intended to address non-digital systems that can include
physical location, other people, external processes, etc.
This part of ISO/IEC 24751 focuses on the description of the characteristics of the resource that affect how it
can be perceived, understood or interacted with by users, including
a) what sensory modalities are used in the resource,
b) ways in which the resource is adaptable, i.e. whether text can be transformed automatically,
c) which methods of input the resource accepts, and
d) what adaptations are available.
This part of ISO/IEC 24751 provides an information model for describing learning resources so that individual
learner preferences and needs (described according to ISO/IEC 24751-2) can be matched with the
appropriate user interfaces, tools and learning resources within a computer-mediated learning environment.
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 639-2:1998 (E/F), Codes for the representation of names of languages — Part 2: Alpha-3 code/Codes
pour la représentation des noms de langue — Partie 2: Code alpha-3
© ISO/IEC 2008 – All rights reserved 1

ISO/IEC 24751-1:2008 (E/F), Information technology — Individualized adaptability and accessibility in
e-learning, education and training — Part 1: Framework and reference model/Technologies de l'information —
Adaptabilité et accessibilité individualisées en e-apprentissage, en éducation et en formation — Partie 1:
Cadre et modèle de référence
ISO/IEC 24751-2:2008 (E), Information technology — Individualized adaptability and accessibility in e-learning,
education and training — Part 2: “Access for all” personal needs and preferences for digital delivery
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.01
access for all
AfA
approach to providing accessibility in a computer-mediated environment in which the digital resources and
their method of delivery are matched to the needs and preferences of the user
[ISO/IEC 24751-1:2008 (2.1)]
3.02
accessibility
usability of a product, service, environment or facility by individuals with the widest range of capabilities
NOTE 1 Although "accessibility" typically addresses users who have a disability, the concept is not limited to disability
issues.
1)
NOTE 2 Adapted from ISO/TS 16071:2003 (3.2).
3.03
access mode
human sense perceptual system or cognitive faculty through which a user may process or perceive the
content of a digital resource
[ISO/IEC 24751-1:2008 (2.3)]
3.04
adaptability
〈e-learning〉 ability of a digital resource or delivery system to adjust the presentation, control methods,
structure, access mode, and user supports when delivered
[ISO/IEC 24751-1:2008 (2.4)]
3.05
adaptation
〈e-learning〉 digital resource that presents the intellectual content of all or part of another digital resource
NOTE Adaptations can also include the adjustment of the presentation, control methods, access modes, structure
and user supports.
[ISO/IEC 24751-1:2008 (2.5)]
1) The source for this adapted definition from ISO/TS 16071:2003 is now ISO/IEC 24751-1:2008 (2.2).
2 © ISO/IEC 2008 – All rights reserved

3.06
adaptation coverage
specification of the nature or genre of the adaptation
EXAMPLE Caption, tactile representation, visual representation, etc.
NOTE See the coded domain in ISO/IEC 24751-2:2008, B.2.
3.07
adaptation type
nature or genre of an adaptation
EXAMPLE Caption, tactile representation, visual representation, etc.
3.08
AfA control flexibility
characteristic of a digital resource that supports control of all functionality using an input device of the user's
choosing, i.e. the user is not restricted to any particular input device
NOTE More than one single input type can be supported by a resource. For example, a resource might support use
by keyboard only and by “mouse” only.
3.09
AfA hazard
characteristic of a digital resource that can be specified as being dangerous to a user
EXAMPLE Flashing animations can trigger seizures in people with photosensitive epilepsy.
NOTE See the coded domain in ISO/IEC 24751-2:2008, B.17.
[ISO/IEC 24751-2:2008 (3.07)
3.10
assistive technology
alternative access system
specialized software and/or hardware used in place of or in addition to commonly used software or hardware
for control, display or processing
EXAMPLES Screen reader, alternative keyboard, refreshable Braille device, screen magnifier.
[ISO/IEC 24751-1:2008 (2.8)]
3.11
digital resource
DR
any type of resource that can be transmitted over and/or accessed via an information technology system
NOTE A digital resource can be referenced via an unambiguous and stable identifier in a recognized identification
system (e.g. ISBN, ISAN, UPC/EAN, URI).
[ISO/IEC 24751-1:2008 (2.11)]
3.12
digital resource component
digital resource included in another resource either physically or logically
NOTE In using the access for all approach, one digital resource component might be replaced by an adaptation,
while other resource components are unchanged.
© ISO/IEC 2008 – All rights reserved 3

3.13
digital resource delivery
presentation of a digital resource by a display
[ISO/IEC 24751-1:2008 (2.12)]
3.14
disability
〈digital resource delivery〉 any obstacle to the use of a digital resource experienced because of a mismatch
between the needs of a user and the digital resource delivered
NOTE 1 Disability in an AfA context is not a personal trait but a consequence of the relationship between the user and
their resource system.
NOTE 2 In an e-learning context, disability refers to a mismatch between the needs of a learner and both the
educational resource and/or the method of delivery.
[ISO/IEC 24751-1:2008 (2.13)]
3.15
disability
〈medical perspective〉 any restriction or lack (resulting from an impairment) of ability to perform an activity in
the manner or within the range considered normal for a human being
NOTE 1 This definition of “disability” is included to ensure that users who may have “legal rights” to assistive
technologies are served.
NOTE 2 Adapted from World Health Organization Document A29/INFDOCI/1, Geneva, Switzerland, 1976.
3.16
display
rendering or presentation of a user interface and/or digital resource in a range of access modes
NOTE Access modes include, but are not limited to, visual, auditory, olfactory, textual and tactile.
[ISO/IEC 24751-1:2008 (2.15)]
3.17
display transformability
characteristic of a digital resource that supports changes to specific aspects of its display
NOTE See the coded domain in B.2.
[ISO/IEC 24751-1:2008 (2.16)]
3.18
display transformation
DT
restyling or reconfiguration of the rendering or presentation of a user interface and/or digital resource
[ISO/IEC 24751-1:2008 (2.17)]
3.19
e-learning
learning facilitated by information and communications technology
[ISO/IEC 24751-1:2008 (2.18)]
4 © ISO/IEC 2008 – All rights reserved

3.20
impairment
〈medical perspective〉 any loss or abnormality of psychological, physiological, or anatomical structure or
function
NOTE Adapted from World Health Organization Document A29/INFDOCI/1, Geneva, Switzerland, 1976.
3.21
individual
human being, i.e. a natural person, who acts as a distinct indivisible entity or is considered as such
NOTE Adapted from ISO/IEC 15944-1:2002 (3.28).
3.22
information technology system
IT system
set of one or more computers, associated software, peripherals, terminals, human operations, physical
processes, information transfer means, that form an autonomous whole, capable of performing information
processing and/or information transfer
[ISO/IEC 14662:2004 (3.1.8)]
3.23
intellectual content
recorded information of a digital resource independent of its representation and/or access mode
[ISO/IEC 24751-1:2008 (2.23)]
3.24
language
system of signs for communication, usually consisting of a vocabulary and rules
NOTE In this part of ISO/IEC 24751, language refers to "natural languages" or "special languages" but not
"programming languages" or "artificial languages".
[ISO 5127:2001 (1.1.2.01)]
3.25
original access mode
access mode through which the intellectual content of the digital resource was originally designed to be
communicated
4 Symbols and abbreviations
The following abbreviations and acronyms are used in this document.
AfA access for all
DR digital resource
DRD access for all digital resource description
DT display transformation
IEEE Institute of Electronic & Electrical Engineering
IMS IMS Global Learning Consortium
IT system information technology system
© ISO/IEC 2008 – All rights reserved 5

MIME multipurpose internet mail extensions
PNP access for all personal needs and preferences
W3C World Wide Web Consortium
W3C/WAI WCAG W3C/Web Accessibility Initiative Web Content Accessibility Guidelines
5 Basic Principles
5.1 Assumptions
For the purposes of the Access For All Digital Resource Description (DPD) it is assumed that content to be
presented to a learner is compliant with basic accessibility specifications as defined in the World Wide Web
Consortium Web Content Accessibility Guidelines [W3C WAI WCAG]. Compliance with W3C WAI priority 1
and 2 ensure that the presentation and control of text is transformable. This avoids the need to provide
multiple static presentations of textual material to accommodate the different needs of individual learners.
This standard assumes that all users, not just individuals with specific impairments, have accessibility
preferences and may need or want to optimize learning by configuring education delivery to meet their
individual needs and preferences. With the increasing variety of interface choices and environments in which
on-line learning occurs, users need to be able to control how they interact. Some of these choices may be
considered personal preferences, while others will be essential to access to content in environments such as
noisy locations, hands free operation, etc.
It is assumed that users have different preferences in different contexts, such as at different times or locations.
5.2 Original and Adapted Resources
The Access For All Digital Resource Description (DRD) assumes two categories of resources: original and
adapted. An original resource is the initial or default resource. An adaptation contains the same intellectual
content as an original resource but in a different form such as in a different sensory mode, or with more or less
dense semantics. Some resources, especially those compliant with W3C WAI Web Content Accessibility
Guidelines, contain several versions of content, such as a video file and text captions as an adaptation of the
auditory content of the video. An original resource may be a part of another resource.
The Access For All Digital Resource Description (DRD) enables metadata authors to record the access
modes used to communicate the intellectual content of their resources. These are called “original access
modes” because generally they were created as the original content of the resource. When an adaptation is
created, as a component of the same resource or in a separate resource, its DRD can refer back to the
original access modes of the resource being adapted. Similarly, when another existing resource is chosen as
an adaptation of the first resource, its DRD can also refer to the original access modes of the resource it
provides an adaptation for.
Many authors of resources are unaware of accessibility considerations and are not motivated or skilled to
provide extensive accessibility metadata. Such authors can supply useful information by identifying the access
modes of the resource, whether the display and method of control of the resource can be transformed, and if
there is a known adaptation. Metadata describing the display transformability and control flexibility of the
resource can be generated using accessibility evaluation tools.
On the other hand, authors of specialized adaptations are likely to be both informed and motivated about
accessibility considerations. Detailed Access For All Resource Descriptions closely match the Access For All
2)
Personal Needs and Preferences (PNP) .

2) Defined in ISO/IEC 24751-2.
6 © ISO/IEC 2008 – All rights reserved

5.3 Access For All Resource Metadata
Access For All metadata for original resources includes:
• Access Mode: whether the user requires vision, hearing, touch and/or text literacy to access the
resource
• Access Mode Usage: whether the content in each access mode is informative or ornamental
• Display: amenability of a resource to transformation of the display
• Control: flexibility of control of a resource
• Adaptations: any known adaptations
and, where appropriate,
• Components: any parts that make up this resource (a sound file, an image, etc.) or a composite
resource of which this resource is a part
• Hazards: any dangerous characteristics
• Support tools: electronic tools associated with the resource (calculator, dictionary, etc.)
Access For All metadata for adapted resources (adaptations) includes the same metadata as for original
resources but also includes the:
• Identity of the original resource: the resource for which it is an adaptation
• Type: kind of adaptation
• Extent: extent of original resource contained in the adaptation
• Detailed description of adaptation: description of characteristics necessary for matching resource
3)
characteristics to a PNP .
The Access for All Digital Resource Description may be used in combination with other Metadata
specifications and standards, or independently. Similarly, metadata bindings employed to describe resources
may integrate the Access for All Digital Resource Description into the more generic binding or apply it
independently.
5.4 Access Mode
The access mode of a resource is not the same as the format of a resource. The format of a resource can be
represented as a MIME type but its access mode will depend upon a combination of its format and its genre:
an image of a poem in a tapestry will have a visual format but a text genre. A user viewing the image on a
screen can read the text of the poem but a screen reader (an assistive technology) cannot access the text as
it is locked in the image.
The important information, from the viewpoint of a user with specific access needs and preferences, is which
sensory modes are required to access the content of the resource. The possibilities are based on the human
computer interface modes of sight, sound, and touch, with an additional special mode, 'textual' to include text
literacy. Text literacy is not the same as literacy in everyday parlance. In this context, text literacy may mean
accessing the content of text by listening to an aural rendition of the text or viewing a transformation of it into
symbolic or sign language, or feeling it as Braille.
If an access mode is not suitable for a user (including after any possible transformations), the content in that
access mode should be adapted by another resource.
As many resources contain multiple files (i.e., aggregate resources), adding the necessary metadata in order
to deliver accessible resources may involve a dis-aggregation of the composite resource into a set of
components. Once such components can be associated with their own access modes (as opposed to being
represented in the aggregation of modes of the original resource), they can be individually matched to a PNP

3) As specified in ISO/IEC 24751-2.
© ISO/IEC 2008 – All rights reserved 7

with access mode requirements. Matching individual components to a PNP ensures that a resource that is
re-aggregated will also match that PNP.
5.5 Adaptability
5.5.1 Display Transformability
The presentation or display of most resources can be transformed if appropriate formats, mark-up or software
development practices are used to create the resources. This requires that the content and content-structure
are independent of the presentation of the content. The means to achieve this is to keep presentational and
structural mark-up separate (see W3C guidelines [W3C WAI WCAG]). This enables the display or method of
presentation to be transformed using styling mechanisms (e.g., Cascading Style Sheets, system based
display settings, XSLT or others).
Display transformability specifies how the display or presentation of a resource (e.g., font colour, font size,
background colour, layout, image size) is amenable to transformation. It can be determined using a number of
4)
available Web content evaluation and repair tools .
5.5.2 Control Flexibility
Some resources can only be controlled using a mouse or mouse equivalent. This means users who do not
have a mouse or cannot control a mouse cannot control such resources. If all of the functions controlled by
the mouse can also be controlled using keyboard commands, users will have access to the same functionality
using a keyboard or any number of other keyboard-emulating devices (e.g., scanning systems, coding
systems, enlarged keyboards, etc.).
Some interfaces require many sequential actions to navigate to a desired control, such as a button. This can
be difficult for some users. Interfaces that allow reconfiguration of the actions required to access specific
controls, buttons, links or input fields enable the optimization of the control method.
Control flexibility describes how the resource supports a choice of methods of controlling the resource
functions. It is anticipated that this will be determined using accessibility-checking tools.
5.5.3 Pointer to Adaptation from Original Resource
When the authors of metadata for original resources are aware of the existence of an adaptated resource,
they can point in the metadata to a known adaptation for the original resource. A description of the adaptation
is recorded in the metadata for the adaptation. Further detail on adaptation metadata is in the next section.
5.5.4 Adaptation Embedded in an Original Resource
When an original resource contains an adaptation (such as a video that contains a text caption), a metadata
record for the original resource will have both an original resource description and an adaptation description.
Thus, both components of the Access for All Digital Resource Description (DRD) record will be completed for
the single resource.
5.5.5 Adaptation Metadata
Adaptations are used two ways: to replace or to augment an original resource. Although in most cases the
original and adapted resources will be separate, an original resource may contain a supplementary adaptation.
For example, a video could have text captions included. In this case the resource would be classified as
original containing an adaptation.

4) The range of possible display transformations is described in the Access For All Personal Needs and Preferences
(PNP) specification in ISO/IEC 24751-2.
8 © ISO/IEC 2008 – All rights reserved

Adaptations are not always complete alternatives (replacements or supplements) to an original resource. For
example, an alternative for a video that contains audio and visual modes may be an alternative for the audio
(e.g., a caption) or for the visual (e.g. a video description). Each adaptation statement must indicate which
access mode the adaptation is for. This detail is required to enable precise matching of resources to a PNP.
Original resources may have any number of adaptations. An adaptation can serve as an alternative to more
than one original resource, but a separate DRD is required to describe each such relationship. That is, by
definition, and adaptation’s DRD must refer to only one original resource. For example, a transcript of Martin
Luther King’s “I Have a Dream” speech could serve as a text equivalent to both a video of that speech and an
audio file of the same speech, as long as two separate DRDs are available.
In a case where an adaptation is derived from another adaptation, such as when there is a French version of
an English transcript, both transcripts are defined as Access for All adaptations of the original resource. (The
resources may have other metadata that describes the derivation of the French transcript from the English
one.)
5.6 The Importance of Interoperability and Consistent Implementation
While interoperability is important for e-learning, the importance is heightened for learners who use assistive
technologies or specialized devices such as refreshable Braille displays, enlarged keyboards or voice
recognition systems. Many people with a physical, sensory or intellectual impairment are dependent on
assistive technologies to use a computer. Because of the diversity of alternative access systems, from an
information technology developer’s perspective every person using an alternative access system potentially
represents a unique external system that needs to interoperate. Additionally, in order to function, each
assistive technology needs to interoperate with a large array of interfaces and applications. Although very
varied, the user base and development base of assistive technologies is very small and under-resourced. For
this reason, it is critical that there is consistency in the implementation and interpretation of these standards to
increase the likelihood of interoperability for assistive technologies.
Whether involving an assistive technology or not, user needs and preferences of people with a disability (in
the traditional sense) are frequently very particular with little or no room for variance. A slight variation in font
size, button size, or background colour, for example, can be the difference between an accessible resource
and an unusable one for a specific user. Ensuring access for users whose choice of access modes is
restricted by an impairment often requires exact matching of a resource with a user’s requirement: in such a
case it is not a matter of convenience or optional refinement but one of utmost importance. As a result, it is
necessary for systems to agree upon well-defined interfaces and for the standard to deter free, non-
conformant extension in its usage. A strictly defined approach is taken in this multi-part standard to support
maximum interoperability.
© ISO/IEC 2008 – All rights reserved 9

6 Access For All Digital Resource Description (DRD) Information Model
The attributes in this information model are described in Clause 7.
6.1 Access For All Digital Resource Description
Attribute Allowed Occurrences Datatype
access mode statement Zero or more per Access For Access_Mode_Statement
All Resource
control flexibility Zero or more per Access For control_flexibility_vocabulary
All Resource
has control flexibility Zero or more per Access For URI
statement All Resource
display transformability Zero or more per Access For display_transformability_vocabulary
All Resource
has display transformability Zero or more per Access For URI
statement All Resource
colour coding Zero or one per Access For boolean
All Resource
hazard Zero or more per Access For hazard_vocabulary
All Resource
has adaptation Zero or more per Access For URI
All Resource
has part Zero or more per Access For URI
All Resource
is adaptation Zero or one per Access For Is_Adaptation
All Resource
is display transformability Zero or one per Access For URI
statement of All Resource
is control flexibility statement Zero or one per Access For URI
of All Resource
is part of Zero or one per Access For URI
All Resource
adaptation statement Zero or more per Access For Adaptation_Statement
All Resource
support tool Zero or more per Access For support_tool_vocabulary
All Resource
6.2 Access Mode Statement
Attribute Allowed Occurrences Datatype
original access mode One per Access Mode access_mode_vocabulary
Statement
access mode usage Zero or one per Access Mode access_mode_usage_vocabulary
Statement
10 © ISO/IEC 2008 – All rights reserved

6.3 Is Adaptation
Attribute Allowed Occurrences Datatype
is adaptation of One per Is Adaptation URI
extent One per Is Adaptation extent_vocabulary
6.4 Adaptation Statement
Attribute Allowed Occurrences Datatype
adaptation type Zero or one per Adaptation adaptation_type_vocabulary
Statement
original access mode One per Adaptation Statement access_mode_vocabulary
extent Zero or one per Adaptation extent_vocabulary
Statement
representation form Zero or more per Adaptation representation_form_vocabulary
Statement
[ISO 639-2:1998]
language Zero or more per Adaptation
Statement
reading rate Zero or one per Adaptation integer range (1 . 300)
Statement
education level Zero or more per Adaptation characterstring
Statement
7 Attribute Descriptions and Recommended Use
This clause describes how the terms in the information model in Clause 6 should be used. In this Clause,
bolded terms are defined in Clause 3, and italicized terms are explained in Annex A of the Framework
document (ISO/IEC 24751-1).
7.1 access for all digital resource description
a collection of information that states how a digital learning resource can be perceived, understood or
interacted with by users
Value space: container
7.1.1 access mode statement
a collection of information that states a primary access mode of a resource and its usage in the resource
Value space: container
7.1.1.1 original access mode
an access mode through which the intellectual content of the resource is communicated, not including any
adaptations
NOTE This does not include the access mode of any adaptations embedded in the resource.
Value Space: auditory, tactile, textual, visual, olfactory
© ISO/IEC 2008 – All rights reserved 11

7.1.1.2 access mode usage
the role of a primary access mode with respect to the intellectual content of a resource
Value space: informative, ornamental
7.1.2 control flexibility
a single input method which is sufficient to control a resource
NOTE More than one item from the vocabulary may be chosen. For example, a resource might support full keyboard
control and full mouse control.
Value Space: full keyboard control, full mouse control
7.1.3 has control flexibility statement
the referenced resource states the control flexibility characteristics of the described resource
NOTE This does not refer to the control flexibility element of the referenced resource’s DRD, but rather to the fact
that the referenced resource itself describes the control flexibility characteristics of the described resource. This might take
the form of a report generated by an automated tool, for example.
Value Space: URI
7.1.4 display transformability
a characteristic of a resource display that can be modified
NOTE This is used to state what display properties are amenable to transformation.
Value Space: font size, font face, foreground colour, background colour, cursor presentation, highlight
presentation, layout, structure presentation
7.1.5 has display transformability statement
the referenced resource states the display transformability characteristics of the described resource
NOTE This does not refer to the display transformability element of the referenced resource’s DRD, but rather to the
fact that the referenced resource itself describes the display transformability characteristics of the described resource. This
might take the form of a report generated by an automated tool, for example.
Value Space: URI
7.1.5.1 colour coding
the described resource communicates some information by use of colour alone
Value Space: true, false
7.1.6 hazard
a characteristic of the described resource that must not be delivered to some users
NOTE For example, flashing animations can trigger seizures in people with photosensitive epilepsy.
Value Space: flashing, sound, olfactory, motion simulation
7.1.7 has adaptation
the referenced resource presents the intellectual content of all or part of the described resource, often in
another access mode
Value Space: URI
12 © ISO/IEC 2008 – All rights reserved

7.1.8 has part
a referenced resource is a resource component of the described resource
Adapted from [DCMI MT]
Value Space: URI
7.1.9 adaptation
a collection of information that states what resource the described resource provides an adaptation of, and the
extent to which it does so
Value space: container
7.1.9.1 is adaptation of
the described resource presents the intellectual content of all or part of the referenced resource, often in
another access mode
Value space: URI
7.1.9.2 extent
the scope of the content of the resource
NOTE When used in this context, this term means how much of the intellectual content in the original resource is
presented in the adaptation.
Value Space: part, all
EXAMPLE An adaptation might use text to convey the con
...