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This is a draft - please comment....



ISO/IEC 24751 is intended to facilitate the matching of individual user needs and preferences with digital resources resources [note:interfaces are used to access resources] that meet those needs and preferences to enable appropriate perception of the resources. This matching might involve finding a suitable resource or interface, or format of a resource, or it might involve adaptation of the resource or its interface. It is intended to address mismatches between personal needs and preferences caused by any number of circumstances, including requirements related to client devices, environments, language proficiency or abilities. The terms and definitions within ISO/IEC 24751 are not judgmental but functionalor based on disability classifications, diagnosis or assumptions regarding disability, rather they are descriptions of functions that can be applied by all users; the purpose is not to point out flaws in  digital in resources or interfaces with respect to accessibility and adaptability, but to facilitate the discovery and use of the most appropriate content and interface components resource, configuration or interface for each user. 

In ISO/IEC 24751, it is recognized that users individuals experience a disability when there is a mismatch between the user's individual’s needs (or preferences) and the perceptual user experience, service or environment delivered. Disability is therefore not viewed as a personal trait but as a consequence of the relationship between a user and an interactive the individual and the environment or resource delivery system. An individual who is blind is not disabled when a the resource is delivered in audio, but an individual who does not have the necessary background knowledge to understand the resource, or an individual who is listening to the resource in a noisy environment, is disabled. Given this re-framingreframing, a resource system is accessible when a user 's needs can be addressed or matched (through adaptation, re-aggregation or substitution of digital learning resources and user interfaces). Accessibility , in practice, is determined by the flexibility of the system or environment (with respect to presentation, control methods, structure, access mode, and intellectual supports, for example) and the availability of adequate alternative-but-equivalent interfaces, content and activities. The needs and preferences of a user may arise from the user's context or environment, the technical requirements of the user's device, the tools available (e.g. assistive technologies such as Braille devices, voice recognition systems, alternative keyboards, etc.), the user's background, or a disability in the traditional medical sense. Accessible ‘systems’ systems adjust the user interface or configuration of the interactive environmentsystem, locate needed resources , matched and adjusted adjust the resources to match the characteristics of the resources to the needs and preferences of a user.

Information technology — Individualized adaptability and accessibility in e-learning, education and training — Part 1: Framework

1    Scope

1.1    Statement of Scope

ISO/IEC 24751 applies to personalization on demand, enabled by ICT and networked systems.

ISO/IEC 24751 is not restricted to classic notions of disability and takes an inclusive approach. It is intended for all users, as every user can experience a mismatch of their individual needs and preferences and the content or services delivered.

ISO/IEC 24751 is framed to support the perspective and understanding of the individual user (in contrast to the technical specifics of an implementation).

This Framework Part 1 of ISO/IEC 24751 provides a common framework for additional parts. These additional parts will may include:

  1. Part 2 that describes in detail the provision, maintenance, availability, form and use of an open, online, digital registry to be called the AccessForAll Registry;
  2. Part 3 Other parts that will specify the definition of data elements to be registered in the AccessForAll (or other conformant registries). It may also specify classes of data elements, such as those associated with a class of visibility, or classes such as those that are mandatory, recommended, or otherwise, and
  3. other parts as deemed necessary to support implementation and provide interoperability and efficiency of this standard.

It is intended that the registry will enable to registration of common terms that can be used to describe users' needs and preferences for the provision of resources. This may involve registration of terms, of schema, or other documents that will be machine-readable and, where appropriate, human readable.

NOTE 1 Many jurisdictional domains have instituted policies or legislation that require equal access to information for individuals with disabilities (as defined by the World Health Organization). ISO/IEC 24751 can be used to assist in meeting these requirements (see Annex C for a list of example policies and legislation).


1  ISO/IEC 24751 is intended to facilitate the matching of resources to user's individual requirements by providing common terms for describing those requirements so they can be matched to resources that satisfy the requirements.
1.2 Exclusions

This part of ISO/IEC 24751 does not describe how to create accessible content.  

Wiki Markup
NOTE Other work exists and standards are under development that describe how resources can be made more accessible \[1\].

Metadata to assert compliance to an accessibility specification or standard is not within the scope of this standard.

Wiki Markup
This part of ISO/IEC 24751 does not (nor do ISO/IEC 24751-2 and ISO/IEC 24751-3) define how to deal with types and roles of Persons, (and two sub-types of Person namely organization and public administration) \[2\]. <span style="color: #ff00ff">Editors' Note -</span> <span style="color: #ff00ff">Is this necessary?</span>

Wiki Markup
\[1\] See for example W3C/WAI Web Content Accessibility Guidelines \[W3C/WAI, WCAG\], ISO 15836, ISO 15706, other standards of ISO/TC 46 and ISO/IEC JTC 1/SC 29, as well as standards being developed by ISO/IEC JTC 1/SC 36.
\[2\] See further ISO/IEC 14662:2004, Information technology --- Open-edi reference model and the ISO/IEC 15944 multi-part e-business standard.

1.3 Aspects not currently addressed Editors' Note - given the registry, many things if appropriate will be addressed so excluding things is not necessary

ISO/IEC 24751 does not currently support individual needs and preferences and resource descriptions related to non-digital resources.

2. Terms and Definitions

Editors' Note - as many of these will not be used in the text of the standard, they are here just is case but can be discarded. They are copied from N 24751 and numbering has not be adjusted.


2.1    Exclusions

2.1.1   Implementation

ISO/IEC 24751 is “implementation neutral” to enable innovation and advances in implementations. As such, the standard will not define more than the way of describing needs and preferences, the related characteristics of resources, the creation and maintenance of a registry of terms, and the policies for that registry.

2.1.2   The creation of accessible content

ISO/IEC N24751 does not  describe how to create accessible content. Other work exists and standards are under development that describe how content and interfaces can be made more accessible.[1|#_ftn1]

2.1.3   Person: organization and public administration

ISO/IEC24751 does not define how to deal with types and roles of Persons, (and two sub-types of Person namely organization and public administration). Other standards exist and are under development that address these and related issues.[2|#_ftn2]

2.2 Aspects not currently addressed

  • · Note – none of this is necessary if the word digital is included with resources in the text ie ‘digital resources’ instead of just resources.

2    Conformance

This document is a framework document and as such there is no conformance to this part of the standard. Requirements for conformance are specified in successive parts of this standard.

3    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/IEC 11179, Information Technology – Metadata Registries (MDR)

ISO 19788, Metadata for Learning Resources (MLR)

4    Terms and definitions

For the purposes of this document, the following terms and definitions apply.


access for all


Wiki Markupapproach to providing *accessibility* (2.2) in a Approach to providing accessibility (4.3) in a computer-mediated environment in which the *digital * * resources* (24.117) and their method of delivery are matched to the needs and preferences of the user \[IMS _AccessForAll Meta-data Specification_ Version 1\]&nbsp; \[IMS _AccessForAll Meta-data Specification_ Version 1\]



usability (2.26user


AccessForAll Registry

A registry of terms to be used in creating PNP statements, resource descriptions, pull statements[3|#_ftn3] and other functions in support of personalization on demand enabled by ICT and networked systems


AccessForAll (AfA) accessibility

usability (4.18) of a product, service, environment or facility by individuals an individual (24.20) with the widest range of capabilities12) according to that individual’s needs and preferences at the time of use

NOTE 1 Although “accessibility” typically addresses users who have a disability, the concept is not limited to medical impairment or disability issues.

NOTE 2 Adapted from ISO/TS 16071:2003, 3.2.2


access mode

human sense perceptual system or cognitive faculty through which a user may process or perceive the content of a digital resource (24.119)2



⟨e-learning⟩ ability of a digital resource (24.119) or delivery system to adjust the presentation, control methods, structure, access mode (24.34), and user supports, when delivered2



⟨e-learning⟩ digital resource (24.119) that presents the intellectual content (24.2314) of all or part of another digital resource (24.119) 

NOTE Adaptations can also include the adjustment of the  the presentation, control methods, access mode, structure and user supports.


AfA agent

someone, i.e. a real person, or something, i.e. automatons (2.7), acting on behalf of an individual (2.20) in a clearly specified capacity in an access for all (2.1) context

NOTE Adapted from definition of “agent” in ISO/IEC 15944-1:2002, 3.1.


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 (2.15) or processing

EXAMPLES Screen reader, alternative keyboard, refreshable Braille device, screen magnifier.


data element, term 4.7

data element, term 

unit of data for which the definition, identification, representation and permissible values are specified by means of a set of attributes

Wiki Markup&nbsp;\ [ISO/IEC 11179-1:2004, 3.3.8\]&nbsp; \  [ISO/CEI 11179-1:2004, 3.3.8\]


dataset, term set

identifiable collection of data  

NOTE A dataset can be a smaller grouping of data which, though limited by some constraint such as spatial extent or feature type, is located physically within a larger dataset. Theoretically, a dataset can be as small as a single feature or feature attribute contained within a larger dataset. A hardcopy map or chart can be considered a dataset.2.11


digital resource DR

any type of resource that can be transmitted over and/or accessed via an information technology system (24.2214)

NOTE A digital resource can be referencedvia an unambiguous and stable identifier in a recognized identification system (e.g. ISBN, ISAN, UPC/EAN, URI).


digital resource delivery

presentation of a digital resource (2.11) by a display (2.15)



⟨digital resource delivery⟩ any obstacle to the 4.10


〈digital resource delivery〉 any obstacle to an individual’s (4.13) use of a digital resource (24.119) experienced because of a mismatch between the needs of a user and the digital resource (24.119) 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 system.2


disability ⟨medical perspective⟩ Wiki Markupany restriction or lack \[resulting from an *impairment* (2.19)\] 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

〈medical perspective〉 any restriction or lack [resulting from an impairment (4.12)] 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, 1976.2



rendering or presentation of a user interface and/or digital resource (2.11) in a range of access modes (2.3)

NOTE Access modes include, but are not limited to, visual, auditory, olfactory, textual and tactile.


display transformability

characteristic of a digital resource (2.11) that supports changes to specific aspects of its display (2.15)

NOTE See the coded domain in ISO/IEC 24751-3:2008, B.3.


display transformation


restyling or reconfiguration of the rendering or presentation of a user interface and/or digital resource (2.11)



⟨medical perspective⟩ 12


〈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.



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. 


individualized accessibility

Wiki Markup
⟨e-learning⟩ facility of an *IT system* (2.22) based learning environment to address the needs of an individual as learner \[through *adaptation* (2.5), re\- aggregation and substitution\]

NOTE Accessibility is determined by the flexibility of the education environment (with respect to presentation, control methods, structure, access mode and learner supports) and the availability of equivalent content deemed to be adequate alternatives.


information technology system IT system

Wiki Markup
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 &nbsp;\[ISO/IEC 14662:2004, 3.1.8\]&nbsp;&nbsp;


intellectual content

recorded information of a digital resource (2.11) independent of its representation and/or access mode (2.3)



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]



system of signs for communication, usually consisting of a vocabulary and rules

Wiki Markup&nbsp;\[ISO 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,\]&nbsp;&nbsp;



Personal Needs and Preferences (PNP) statement

A statement containing a value associated with a data element (term) (4.7) for describing the needs and preferences of an individual. Needs and preferences statements may be conditional.


Personal Needs and Preferences (PNP set

A dataset (4.8) (collection) of Personal Needs and Preference statements (4.16). Each individual may have multiple PNP statements and/or sets.


Personal Needs and preferences (PNP) context set

A (named) dataset (4.8) of conditions to determine if a PNP statement (4.16) applies[4|#_ftn4]


Personal Needs and preferences (PNP) context name

A name associated with a PNP context set (4.17).



extent to which a product can be used by specified users to achieve specified goals, with effectiveness, efficiency and satisfaction, in a specified context of use

Wiki Markup&nbsp;\[ISO 9241-11:1998, 3.1\]&nbsp; \[ISO 9241-11:1998, 3.1\]


user experience

those aspects of interfaces or resources that a person experiences including but not limited to interfaces, presentations, augmentations (e.g. captions, descriptions), alternate resources (e.g. a different way to learn about gravity that doesn’t require vision), language, culture, and cognitive complexity.

3 Symbols and abbreviations

AfA access for all

DR digital resource

DCMI Dublin Core Metadata Initiative

DT display transformation

EDI electronic data interchange

FDT Formal Description Technique

FSV Functional Services View IMS IMS Global Learning Consortium

HIE Human Interface Equivalent

ISO International Organization for


IEC International Electrotechnical


IT information technology

IT system information technology system

JTC 1 Joint Technical Committee 1 (of ISO/IEC)

RS Registration Schema

UML Unified Modelling Language


5    Symbols (and abbreviated terms)

AfA                         access for all

ICT                         Information and communication technology

IMS                         IMS Global Learning Consortium

IEC                         International Electrotechnical Commission

ISO                         International Organization for Standardization

IT                            Information technology

MLR                        Metadata for Learning Resources

W3C                       World Wide Web Consortium

W3C/WAI WCAG WCAG     World Wide Web Consortium/Web Accessibility Initiative Web Content Accessibility Guidelines


6    Basic Principles

4.ISO/IEC 24751 is constructed to enable interoperability as well as innovation and extensions, not to constrain.

The standard recognizes each user as an individual with individual needs and preferences.

The Personal Needs and Preferences (PNP) of an individual may differ according to their context so each individual can have multiple needs and preferences statements.

Each individual should be able to continuously refine the match provided and their individual PNP statements.

The standard will be “implementation neutral” to enable innovation and advances in implementations.

The standard will be interoperable with MLR (ISO/IEC N19788).

Only the user makes a judgment regarding the urgency or importance of a needs and preference request.

Terms not in the AccessForAll Rgistry can be used in implementing AccessForAll.

6.1 The Matching Process

This standard enables a matching process by providing for common terms to be used for descriptions of user requirements and the relevant characteristics of resources and user interfaces so they can be matched. It does not specify how matches are to be made although examples of systems that make matches are provided in Appendix 1.

4.2 Basic Principles for this standard include the following:

  1. It is envisaged that descriptions of requirements may be specified by users or generated by suitable algorithms but, in both cases, users' choices will be given priority in determining the profile of requirements they want to use at any time.
  2. It is understood that some users will have conditional requirements such as "from 8 am to 6 pm I would like white text on black but from 6 pm to 8 am I would like  yellow text on blue".
  3. Some users will specify requirements without which they cannot perceive a resource, essential requirements, needs, and some users will also want to specify preferences in cases where they can manage without the requirement but find it easier if they can have it.

4.2 The goal is to facilitate the provision of a user experience that matches the needs and preferences of a user by providing a framework for the definition of common terms describing:

•       user needs and preferences and user experiences available from a device and resource


•       a method and format for maintaining and publishing a registry of such common terms.

The standard defines description terms for Personal Needs and Preferences (PNP) statements with values that can be selected by a user or their agent. PNP statements will take the form of

  • a property definition (to be identified by URL);
  • a value set for that property, and
  • conditions for the operation of that preference.

At any time, an individual’s PNP set will be those PNP statements that are resolved according to the conditions identified by a PNP context set or PNP statements otherwise identified. Where there is a conflict between preference values, the first occurrence within the set will be given priority, independently of when the preferences were stated.

6.3 Extending the Standard

This multi-part standard can be extended by adding additional parts. In general, the standard will be extended by registration of new terms (data elements) and other resources on in the AccessForAll Registry according to this standard and, in particular, Part 2 of this standard.

4.3 Disability and accessibility

Metadata can be used for two accessibility related purposes: to record compliance to an accessibility specification or standard (e.g. for adherence to legislated procurement policies) or to enable the delivery of resources that meet a user's needs and preferences. This multi-part standard addresses the latter purpose. Metadata to assert compliance to an accessibility specification or standard is not within the scope of this standard.

This standard facilitates the selection for an individual user of appropriate digital resources when available thereby providing user experiences that adapt to individual needs. Because these specifications offer a modular approach to accessibility, by defining each aspect of a user preference or resource characteristic separately, systems can determine in individual cases if a resource is accessible, a facility that is not supported by existing accessibility guidelines.

The Access for All resource descriptions are not merely intended to assist with aspects of resource discovery. The AccessForAll Registry of resource descriptors and this overall standard provide an interoperable framework that supports the substitution and augmentation of a resource or component of a resource with an adaptation or component as required by the accessibility needs and preferences of each individual user. For example a textual caption could be added to a video when required by a user with a hearing impairment or in a noisy environment. Alternatively an interactive resource requiring a mouse for operation could be replaced with a resource that can be controlled using a keyboard or keyboard emulator for a user with a mobility impairment or a user operating a device without a mouse.

The complementary aspects of this standard address several challenges including:

  • • initial discovery of material having appropriate accessibility support;  
  • • adjustment (adaptation) of control and display characteristics of digital resources to meet a user's accessibility needs and preferences; and
  • • discovery of appropriate alternative or supplementary representations of desired digital resources. 

This standard exploits the capability of an IT system to translate or transform user interfaces and digital resources for delivery. The first approach to meeting the specific needs and preferences of a user would be to transform the digital resource through alternative presentation styling or through the provision of alternative control methods (e.g. keyboard shortcuts).  This can sometimes be accomplished through the configuration options of the operating system. the rendering options of the application, the styling of the user interface and content, or through an assistive technology. If a digital resource cannot be adequately transformed an alternative digital resource will be required.

4.4 The importance of interoperability and consistent implementation 

While interoperability is always important, the importance is heightened for users who depend upon assistive technologies or specialized devices such as refreshable Braille displays enlarged keyboards or voice recognition systems. Many individuals with a physical sensory or intellectual impairment are dependent on assistive technologies to use an IT system. From an information technology developer's perspective every individual using an assistive technology potentially represents an external system that needs to interoperate. In fact, because of the diversity of assistive technologies, every user of an assistive technology 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. The user base and development base of assistive technologies are 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 using an assistive technology or not, user needs and preferences of individuals with a disability (from a medical perspective) 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 digital resource and an unusable one. Ensuring access for users whose choice of access modes is restricted by impairment often requires exact matching of a digital resource with a user's requirements: 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 specification to deter free non-conformant extension in its usage. A strictly defined approach is taken in this multi-part standard to support maximum interoperability and minimize costs.

Part 1 (Section 5) of this standard provides an abstract model for metadata for this standard. It is based on the Metadata for Learning Resources standard, ISO JTC1 N:19788 and is fully consistent and interoperable with Dublin Core Metadata (ISO N:???) and the Resource Description Framework (W3C …).

By providing for maximum interoperability of AccessForAll metadata, this standard not only caters for accessibility concerns but also makes it easier for general systems to include AccessForAll metadata.

5 Abstract model

Editors' note: there is a lot to be done here

A graphic and textual representation of an abstract model of the Parts and processes described in this
multi-part standard, including those related to the AccessForAll Registry, is presented in this Clause. 

Readers not familiar with UML class diagrams should note that lines starting with a block-diamond should be read as “contains a” or “has a” (for example “a needs and preferences has zero or more contextual descriptions”). Other relationships are labelled appropriately. Image Removed

Figure 1: the creation of a user's profile of requirements and provision of a suitable resource
Image Removed

Figure 2 “Matching Process diagram” illustrates a possible process for matching a digital resource to a user's needs and preferences represented as an UML process diagram.

6 Multilinguality

Editors' note: how this is handled in the registry etc needs to be clarified here....

7 Conformance

This document is a framework document and as such there is no conformance to this part of the standard. Requirements for conformance are specified in successive parts of this standard. 

ISO/IEC 24751-2 AccessForAll Registry conformance is dependent on the function or role played by the conformant technology or application.

ISO/IEC-3 data element conformance depends upon publication data elements.

of free (no-cost) Digital resources are conformant when the metadata record of the digital IT systems are conformant when they gather and/or process Personal Needs and Preference descriptions as specified in ISO/IEC 24751 to deliver digital resources that match each user's needs and preferences.

Metadata authoring tools are conformant if they assist in authoring metadata that includes data elements as specified in ISO/IEC 24751.

Assistive technologies in a specific class are conformant when they respond to the generic elements of ISO/IEC 24751 that apply to that class (e.g., screen readers would respond to screen reader elements). Editors’ note: this notion of ‘generic’ has to be sorted.

What should be standardized

  1. Principles
  2. Registry of CORE/COMMON TERMS --  and Registry Entry Format  
    1. ID, <NAME>, value range, description
  3. Process for Adding new COMMON TERMS  (Core and "New")
  4. Location of CORE Registry
  5. How to create Application Specific Registries  < SEPARATE PART
  6. "Containers"< SEPARATE PART## COMMON  (contexts / configuration) for adapting a profile (or for switching to a different one?)
      1. device (that is being adapted)   Phone vs 
      2. contextually responsive  
      3. environmental
  7. User specific Conditions for switching profiles
    1.  (when I am in my smaller AMIGO vs when I am at my desk)  

Wiki Markup
&nbsp;\[[LN1]\]Education is concerned with both learners but also teachers and administrators etc. So "user"is more appropriate than 'learner'.


Parts 2 and 3 of this standard.

7    Description of AccessForAll Registry

The AccessForAll (AfA) Registry will support interoperability and re-use of terms while enabling agile updating and extensions.

The Registry will not standardize the binding to be used.

The Registry will establish a mechanism to enable open and public proposals for new terms.

To support interoperability and reuse, the Registry will establish classes of terms and an agreed upon structure and format for listing terms.

The content of the registry will be interoperable with popular meta-data standards, including the MLR.

Use of the terms within the registry will be free and open.

The registry will establish a lightweight, minimally formalized process for sanctioning new terms.


[1|#_ftnref1] See for example W3C/WAI Web Content Accessibility Guidelines [W3C/WAI, WCAG], ISO 15836, ISO 15706, other standards of ISO/TC 46 and ISO/IEC JTC 1/SC 29, as well as standards being developed by ISO/IEC JTC 1/SC 36.

[2|#ftnref2] See further ISO/IEC 14662:2004, _Information technology — Open-edi reference model and the ISO/IEC15944 multi-part e-business standard.

[3|#_ftnref3] Pull statements are requests to fill gaps in meeting a PNP statement.

[4|#_ftnref4] The stress is on the individual’s perspective. A condition should be clear: for example, an objectively determined condition such as ‘if it is raining’ does not indicate if the user is affected by the rain, as they may be sheltered or have an umbrella.