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Accessible PracticesBest PracticesWeb Page Design

Although it may seem that the World Wide Web has been like the Wild Wild West – where there are no laws and each frontier web site is on its own – there are significant legal and economic reasons for ensuring inclusion and functionality through accessible web design.
Cynthia Waddell, "Electronic Curb Cuts: Universal Access for Everyone"

Accessible web pages benefit all World Wide Web users, including people with disabilities. For example, when you design pages that will run on a variety of browsers, old and new, you ensure access to your site for more users. On the pages that follow, we outline a nine-step process that has proven useful to us.

For further guidance, we add an annotated list of documents and tools on the Internet. You will find a summary of links related to accessible web page design at the bottom of the page. As with designing programs and exhibitions, flexibility and feedback are essential. We strongly recommend that you ask Internet users who are blind or have low vision to give you feedback early on and throughout the design process.

Process for Designing Accessible Web Pages

  1. Study advice on how to make web pages accessible. By familiarizing yourself with this information first, you will have accessibility principles in mind as you engage in the design process. You can then incorporate them into your work, saving time later when you check your design and make corrections. The following resources can help. The first two sites have good introductory materials on accessible web design. The third, the Web Content Accessibility Guidelines, is the a place to turn with your specific design questions.

    Six Principles of Accessible Web Design: An Introduction to the WAI Page Author Guidelines
    This article summarizes the principles upon which accessible web design is based. This document is a good place to start before getting into detailed guidelines.

    Web Content Accessibility Guidelines 1.0
    The Web Content Accessibility Guidelines (WCAG), produced by the World Wide Web Consortium (W3C), describe what makes a web site accessible for people with disabilities. This document is the most frequently recommended for clarifying questions about accessible web design. WCAG is thorough, but you may find it convoluted. There are several support documents linked to WCAG to make it easier to use.

    Captioning and Audio Description on the Web
    This document explains how to make web-based multimedia accessible. The producer of this page, the National Center for Accessible Media, is a leader in researching accessible multimedia design and has developed software, available through this site, to facilitate captioning of web-based videos.

    Curriculum for Web Content Accessibility Guidelines 1.0
    This slide show produced by the World Wide Web Consortium (W3C) provides comprehensive online instruction and examples that explain its guidelines for accessible web page design.

    Section 508 of the Rehabilitation Act
    In December 2000, the U.S. Access Board issued standards for the accessibility of government web pages. This site links to the standards and answers frequently asked questions.

    Equal Access to Software and Information (EASI)
    EASI provides distance learning courses on using technology to create a barrier-free exchange of information.

    Java Accessibility
    Sun Microsystems' Enabling Technologies Program provides information and downloads regarding Java accessibility.

  2. Create your web pages, keeping accessible design in mind.

  3. Validate the HTML on your pages. A validator checks a document's HTML against a document type definition to ensure that the syntax of the HTML is correct. Validating your HTML documents can be the most important and easiest thing you do to aid accessibility. Many browsers recover from authoring errors, but each one recovers differently. Some methods of recovery alter the appearance or content of your pages. You can minimize these risks by validating the syntax of your HTML. Below we list some validators we have used on our pages.

    Developed by the Center for Applied Special Technology (CAST), Bobby validates HTML and checks platform independence for your pages. Bobby also checks pages for compliance with Web Accessibility Initiative guidelines. You can use Bobby online or download it from this web site.

    Tidy is able to fix a wide range of problems and brings to your attention things you need to work on yourself. Each item found is listed with the line number and column so you can pinpoint the problem in your markup. Tidy will generate a corrected version of the page it checks unless it is unsure how to handle a particular problem. This link allows you to download a free version of the tool and provides directions on its use. TIDY was developed through the World Wide Web Consortium (W3C).

    HTML Validation Service
    The World Wide Web Consortium (W3C) HTML validation service checks HTML documents for conformance to W3C HTML and XHTML recommendations and other HTML standards.

  4. Check your pages for platform independence. No matter which browsers your readers are using, everyone should be able to get the same content and interact in equivalent ways with your site. Web pages should not depend on a certain resolution, color depth, font size, or window size. Platform-independent web pages are accessible regardless of the user's platform and settings. You can check platform independence by viewing your pages with various browser settings and platforms or by using an authoring tool, such as Bobby (see above).

    The following links are for downloadable screen reader demonstrations. A screen reader is user-side software that converts text on the computer into synthesized speech. Such software enables people who are blind or have low vision to navigate the Internet. At present, there are many screen readers for PC computers, but only a few for Macs.

    JAWS is a Windows-based screen reader produced by Henter-Joyce. Called "cutting edge" by some, JAWS is able to trouble-shoot problems that other screen readers have difficulty dealing with. The site has a downloadable demonstration of JAWS, as well as image enlarging-software, called MAGic.

    Lynx is a text-mode web browser sometimes used by people who are blind. Lynx is distributed under the GNU Public License. That means it is free for all to use, modify, and redistribute, as long as it is kept in the public domain.

    ALVA produces outSPOKEN, a screen reader for both PC and Mac. At this site there are downloadable demonstrations for several versions of outSPOKEN software.

    Alternative Web Browsing
    W3C has created a list of links to screen readers, browsers developed especially for people with disabilities, and other methods for accessing the web.

  5. Check again for accessibility. You will address many accessibility concerns by validating and making your web pages platform-independent. You deal with any remaining concerns by returning to the web accessibility guidelines you looked at in Step 1 or by using the following checklist.

    CAST's Bobby program checks pages for compliance with Web Accessibility Initiative guidelines.

    Checklist of Checkpoints for Web Content Accessibility Guidelines 1.0
    The Checklist summarizes the W3C's guidelines in a relatively easy-to-use, succinct manner. Checkpoints from the Guidelines are prioritized according to the degree to which failing the checkpoint makes a site inaccessible. We have found this list to be quite helpful.

  6. Edit your web pages as necessary to increase accessibility.

  7. Test the usability of your web pages with real people. Talk to staff or volunteers who can test the accessibility of your web pages. Perhaps members of your institution's access advisory committee would be willing to help you with testing. You can also seek help from outside sources. See our page on Working with People with Disabilities to find out more about recruiting advisors with disabilities.

    Be sure that you include people with various disabilities – hearing impairments, low vision, and mobility impairments – in your testing team. Be specific about what you want your testing team to examine.

  8. Advertise the accessibility of your web pages. There are several symbols you can use to indicate that you have attempted to make your site accessible. Using these symbols is a form of self-promotion and an encouragement for other institutions to follow your example. The following sites have downloadable icons that reflect various aspects of web accessibility. Respect the regulations for the use of these symbols.

    Once your Web site receives a Bobby Approved rating, you are entitled (though not required) to use the Bobby Approved icon on your site. This icon identifies your organization as one that is committed to inclusion. You can get to icon guidelines for the Bobby Approved symbol through the Bobby web site.

    Conformance to Web Content Accessibility Guidelines 1.0
    The conformance icons indicate the degree to which your site or page conforms to the Web Content Accessibility Guidelines 1.0. This page tells you how to download and include the icons on your page. The Guidelines themselves explain the levels of conformance and which icon would be appropriate for your pages.

    Web Access Symbol
    The Web Access Symbol may be used by webmasters to denote that their site contains accessibility features to accommodate the needs of disabled users. There is no charge to use this symbol, and it may be used in electronic or printed form.


Links Related to Accessible Web Page Design

World Wide Web Consortium (W3C)
The World Wide Web Consortium (W3C) is the most frequently recommended site for information on web accessibility. W3C is an organization that develops web specifications, guidelines, software, and tools. Although geared to experienced web professionals, the site provides documents and links helpful to less experienced web designers. On this site, or linked to it, are guidelines, validators, browsers, checklists, icons, discussion groups, and more.

Accessible Web Authoring Resources and Education (AWARE)
The HTML Writers Guild established AWARE to serve as a central resource where web authors could learn about web accessibility. The AWARE Center provides arguments for accessible web design, practical advice, tools, case studies, and links to 10 top web accessibility sites.

Disabilities, Opportunities, Internetworking, and Technology (DO-IT)
DO-IT's site provides guidelines and comprehensive listings of web resources for accessible web design, adaptive technology, college and career transition, faculty awareness, and other disability-related issues.

National Center for Accessible Media (NCAM)
NCAM is a research and development facility that works to make media accessible to underserved populations, such as disabled persons, minority-language users, and people with low literacy skills. This site provides access to the Web Access Symbol, information on captioning and audio description on the web, and MAGpie, a tool that facilitates captioning web-based videos.

Trace Research and Development Center
The Trace Center works on ways to make standard information technologies and telecommunications systems more accessible and usable by people with disabilities. Trace has information on a variety of assistive technologies. The section on web accessibility has links to guidelines, tools, browsers, forums for discussing web accessibility, and more.

Usable Web
Usable Web is a collection of links about human factors, user interface issues, and usable design specific to the World Wide Web. Topics covered include guidelines, browsers, tools, and user testing.


This web site is not intended to offer legal, architectural, engineering, or similar professional advice. Refer specific questions to an attorney or an ADA authority.

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