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Why Standards Harmonization is Essential to Web Accessibility

Note: This document is a draft [see change log in progress] and should not be referenced or quoted under any circumstances. This document is under development by the Education and Outreach Working Group (EOWG).


This document explains the key role that harmonization of standards plays in increasing accessibility of the Web for people with disabilities. It examines how adoption of a consistent standard for Web content accessibility would drive more rapid development of authoring tools that support production of accessible Web content, making design and development of accessible Web sites more efficient.

This document also explains how adoption of a consistent standard for browser and media player accessibility would improve access to and reinforce the accessibility of Web content, and help ensure that accessible content will be more available through assistive technologies used by some people with disabilities.


In this document "standards harmonization" refers to the adoption of a consistent international set of technical standards for accessibility of Web content; for accessibility of browsers and media players; for production of accessible content by authoring tools used to develop Web content, and accessibility of the authoring tools themselves.

Around the world there is currently fragmentation -- multiple, divergent technical standards -- rather than harmonization of Web accessibility standards. While W3C's Web Content Accessibility Guidelines 1.0 (WCAG 1.0) is the most broadly adopted Web accessibility standard internationally, many countries have developed or are in the process of developing their own versions of technical  guidelines or standards.

Furthermore, there is sometimes one version of a guideline or standard at the national level, different versions at the provincial or state level, and yet different versions adopted by commercial, educational, and non-governmental organizations within the same country. For organizations with audiences spanning different regions or economic sectors, simply keeping track of the different requirements can be a challenge.

Harmonization of Web accessibility standards is key to making an accessible Web because it creates a unified market for authoring tools which produce conformant content, and this unified market drives more rapid development of improved authoring tools. Improved authoring tools make it easier to create accessible Web sites, and to repair previously inaccessible sites, for instance by prompting for accessibility information such as alternative text for graphics, captions for audio, or summaries for data tables. Widespread availability of improved authoring tools can enable accessible design to become the prevailing design mode, even for Web developers minimally aware of the rationale for Web accessibility, or disinclined to learn the guidelines and techniques for accessibility.

Standards harmonization also creates a more attractive market for developers of tools used to evaluate Web content accessibility. It enables re-use of training and technical assistance resources for Web accessibility across different regions and economic sectors. Standards harmonization enables better access to information through browsers and media players, and better interoperability with specialized technologies that some people with disabilities must rely on. It enables development of information repositories containing accessible, compatible, and re-usable content.

The World Wide Web Consortium (W3C) Web Accessibility Initiative (WAI) has developed:

Together these three WAI guidelines provide mutually reinforcing solutions which result in more comprehensive and effective accessibility. W3C/WAI continues to advance these three guidelines by updating and refining them as Web technologies evolve.

Current Situation

Different types of modifications (fragmentation) of Web accessibility guidelines can impact progress on Web accessibility in the following ways:

Various factors currently contribute to the fragmentation of Web accessibility standards.


Web Development

For Web developers using today's authoring tools, development of accessible Web sites first requires an awareness of the need for Web accessibility, then a deliberate effort to apply WCAG 1.0. It may require working around features of authoring tools that make it hard to build accessible Web sites. For instance, some authoring tools still produce non-standard markup. Authoring tools that conform to ATAG 1.0 would provide built-in support for production of accessible Web sites.

Development of accessible Web sites with today's authoring tools may also require Web developers to work around inconsistent support of Web standards needed for accessibility support in browsers and media players. For instance, inconsistent initial support in browsers for Cascading Style Sheet (CSS) features, such as CSS positioning, led many Web developers to rely on less accessible design solutions for layout for many years. Browsers and media players that conformed to UAAG 1.0 would provide reliable support for accessibility features, making the jobs of Web developers much easier.

Web developers must already learn a variety of Web languages and tools in order to be competitive in their field. Harmonization of Web accessibility standards enables Web developers to learn one consistent set of guidelines and implementation technique, rather than needing to learn many different guidelines; and allows them to re-use training and technical assistance resources among a broader Web community.

Authoring Tools

Increased availability of authoring tools conforming to the Authoring Tool Accessibility Guidelines 1.0 (ATAG 1.0) is key to making the Web accessible because with such tools, Web content developers could more easily and more automatically create accessible Web sites.

Authoring tool developers face competing priorities when deciding which features to build into their software. Product managers' decisions with regard to which features are included in product releases are frequently based on the extent of demand for a given set of features throughout their customer base. Harmonized standards mean a more unified customer demand. This strengthens the business case for accessibility for authoring tool developers and can tip the balance towards implementation of more accessibility features in their products. This, in turn, means more rapid availability of authoring tools with features supporting production of accessible content.

Evaluation Tools

Developers of evaluation tools (used to evaluate the accessibility of Web content) are also impacted by fragmented standards which can delay or increase the development cost of evaluation tools. In some cases, additional time needed to implement evaluation tests for multiple versions of guidelines takes away from development time that could otherwise be used to increase the accuracy of evaluation tools, or the usability of the tools themselves.

Harmonized Web accessibility standards allow developers of accessibility evaluation tools to concentrate their efforts on implementing one set of evaluation tests rather than multiple tests for overlapping or conflicting guidelines and standards in different regions or sectors where their products are used. Improved evaluation tools enable more people to test Web sites more reliably, and help ensure more accessible Web sites.


When there is fragmentation of standards, organizations with audiences spanning different regions, countries, or sectors must monitor multiple sets of requirements. Organizations may need to provide different authoring tools, evaluation tools, training resources and technical assistance for their Web developers, which can take resources away from actually implementing accessibility. The increase in cost and effort due to the fragmented standard may make it more difficult to secure acceptance within the organization of the business case for accessibility.

Harmonized Web accessibility standards, on the other hand, allow these organizations to re-use authoring and evaluation tools, training, and technical assistance throughout the organization, thereby achieving more cost-effective accessibility solutions.

Browsers, Media Players, Assistive Technologies

Harmonization of Web accessibility standards is also a concern with regard to browsers and media players. Conflicting standards for browser accessibility can slow implementation of accessibility support. The current lack of browsers and media players conforming to the User Agent Accessibility Guidelines 1.0 (UAAG 1.0) makes it harder for people with disabilities to access information on Web sites, and to find and use accessibility features that are included in some browsers.

Some of today's browsers and media players do not provide access to accessibility information that a Web content developer may have included in a Web site, for instance long descriptions of complex visuals such as maps and graphs, or summaries of information in data tables. UAAG 1.0 describes how browers and media players can enable access to such information when it is present.

UAAG 1.0 also describes requirements for browsers and media players that can work smoothly with assistive technologies which some people with disabilities use -- such as screen readers, screen magnifiers, and voice recognition software.

Implementation of accessibility standards in browsers and authoring tools is mutually reinforcing. Once browser developers implement Web accessibility features, authoring tool developers have more reason to provide authoring support for those features. For instance, once browsers provide access to summaries of data tables, authoring tool developers then have a stronger rationale to provide a means for content developers to add summaries to tables. Similarly, browser developers are influenced by what authoring tools support, and are more likely to implement accessibility features once they know that authoring tools will provide the relevant authoring support.

Information Repositories

Online information repositories allow individuals and organizations to pool content, for instance for the creation of re-usable online learning modules. If the content in an information repository conforms to a consistent accessibility standard, then that content can be shared among an unlimited number of users, and re-purposed and personalized according to user profiles which may include information on prefered learning styles and the accessibility requirements of users with disabilities. With harmonized standards for accessibility of content in the information repository, educators and learners are able to freely transform shared resources according to user needs.

Action Steps

W3C continues to update and refine the WAI guidelines and supporting techniques documents and other resources to keep pace with evolving Web technologies. In addition it is addressing factors which have contributed to fragmentation in the past, such as the lack of an authorized translation process.

WAI is currently developing the Web Content Accessibility Guidelines 2.0 with broad international participation, and with the intent that WCAG 2.0 will be easier to understand and easier to implement; will be more precisely testable; and will address more advanced Web technologies. Broad public feedback on Working Drafts of WCAG 2.0, as well as other WAI guidelines and resources, helps ensure that these documents will continue to meet a broad spectrum of needs.

The following steps can increase the international harmonization of Web accessibility standards, and help lead more rapidly to an accessible Web:

  1. Participate in development of WCAG 2.0 and ATAG 2.0 by reviewing and commenting on drafts, providing feedback during implementation trials, and/or participating in WAI Working Groups.
  2. Promote awareness among policy-makers, standards developers, technology developers, and disability communities of the strategic importance of standards harmonization towards achieving an accessible Web.
  3. Ensure that authoring tool developers, and browser and media player developers, are aware of the need for ATAG- and UAAG- conformant tools, and how implementation of ATAG and UAAG can improve interoperability with assistive technologies and accelerate overall progress on Web accessibility.
  4. For organizations which currently have guidelines that diverge from international standards, consider establishing mechanisms for rapid review and potential transition to WCAG 2.0 once it is completed.
  5. Assist in preparing authorized translations of WAI guidelines.
  6. Redirect energies from development of parallel standards to building awareness and providing implementation support for Web accessibility.

Related Resources

Last updated 1 March 2006 by Judy Brewer.

Editor: Judy Brewer. Contributors: Participants of EOWG.

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