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Web Posted on: November 18, 1998


Accessibility on the Web: Evaluation & Repair tools to make it possible

David Clark
CAST, Inc.
39 Cross Street
Peabody, MA 01960
U.S.A.
dmclark@cast.org

Daniel Dardailler
WAI Project Manager
W3C/INRIA
2004 Route des Lucioles
06902 Sophia Antipolis
FRANCE
danield@w3.org

Introduction

Accessibility on the web is a constant issue. Some developers do not have the background, knowledge, or interest to learn the details of developing sites that are fully accessible. However, there are many tools and services available to encourage this work. This presentation will give an overview of these tools.

Background and Definitions

Many people are working on the definition of accessibility of the web. Historically, this has included, among others, Trace, WGBH/NCAM, and U Toronto/ATRC. Last year, the World Wide Web Consortium (W3) created the Web Access Initiative (WAI) to integrate all of these parallel efforts. One of the document that WAI is writing is an integrated set of guidelines for page authors: the WAI Accessibility Guidelines: Page Authoring.

As the web evolves, these guidelines apply to a wider audience. The same adaptations that make a page usable by someone who is blind also help the person who is accessing the page with a telephone browser. It is no longer an issue of creating "accessible" pages, but rather it is creating "universally designed" pages - pages that work in any browser with any modality.

There are many ways to address these issues on existing pages. The tools fall into 3 categories:

  1. Evaluation tools: Perform a static analysis of pages or sites regarding their accessibility and return a report or a rating. Some validation tools check HTML/CSS in general without accessibility as the focus (the move towards universal design).
  2. Repair Tools: Help page author/webmaster to fix their page.
  3. Filter/Transformation Tools: Help web users to access page (mostly proxy kind: a piece of software sitting between the user and the target server that process the data to improve it). Note that they are all evaluation tools as well, since if a tool can't transform it in a decent way, it probably means its broken beyond repair.

Examples of the available tools

Bobby (http://www.cast.org/bobby/) - The benchmark of accessibility evaluators. It is a web-based public service offered by CAST that analyzes web pages for their accessibility to people with disabilities as well as their compatibility with various browsers. Also available as a downloadable application.

WebMetrics Tool Suite (http://www.nist.gov/webmetrics/) 7 A Suite contains rapid, remote, and automated evaluation tools to help in producing usable web sites. All three programs are downloadable applications.

W3C HTML Validator (http://validator.w3.org/) - An easy-to-use HTML validation service based on an SGML parser. It checks HTML documents for compliance with W3C HTML recommendations and other HTML standards.

Lynx Me (http://ugweb.cs.ualbe rta.ca/~g erald/lynx-me.cgi) - A filtering tool that displays how a page will be rendered in Lynx.

Conclusion

There are many other tools for the evaluation and repair of web pages. For the most up-to-date list, see the WAI's list of existing tools at http://www.w3.org/WAI/ER.