An estimated 750 million people worldwide are disabled. Can they use your Web site? Designing an accessible Web site isn't hard or expensive, and it can increase your potential audience.

The disabled are a large audience with growing political clout. In 1996, the US Justice Department ruled that Web sites are public accommodations that fall under the Americans with Disabilities Act. In January 2001, the US government gave all government Web sites until June 21 to comply with Section 508 of the Rehabilitation Act of 1973.

Since Web site accessibility is a major initiative for government Web sites, it's only a matter of time before civil suits force non-governmental Web sites to likewise address disabled access.

Designing an accessible Web site isn't hard or expensive, and can increase your potential audience by 20 percent. Even so, many Web designers have been surprisingly resistant to the idea of Web site accessibility, believing accessible means boring, text-heavy pages with no graphics. In fact, most design techniques that make a page accessible to disabled users increase the usability level for all users. All it takes is good coding technique and attention to detail. Most existing Web sites need only minor changes to make them accessible.

Accessible Web pages must be usable by visitors with a variety of handicaps that go beyond the obvious problems that deaf and blind visitors experience. You also have to consider the needs of visitors who have limited mobility, color blindness, epilepsy, and other types of physical disabilities.

It sounds like a monumental task. In most cases, though, you can design an accessible Web site by following these five guidelines:

1. Provide a text equivalent to any information you present with graphics, videos, applets, and other non-text content. Use the text to describe the object's content or function. Always include a descriptive ALT tag with all images.

2. Always provide text links on your page if your primary navigation structure relies on image maps.

3. Employ colour and contrast wisely. Don't use colour as a primary means to impart information. Choose colours and colour combinations carefully. Pay close attention to text and background colour contrast--no more blue text on a black page, please!

4. Clearly label your links as links and describe the destinations.

5. Provide alternatives to JavaScript and other DHTML techniques you use for any critical functions on your Web page. Any device-dependent navigation scheme excludes some disabled visitors.

Visit the World Wide Web Consortium's Web Content Accessibility Guidelines page for more detailed information about Web content accessibility and tips on how to bring your page into compliance.

Testing your site
Still not sure how your site stacks up? Test it using these free resources:

Bobby: Evaluates pages for accessibility and flags problems. From the Center for Applied Special Technology (CAST). Sites that pass the test are eligible to display the "Bobby Approved" icon.

Lynx Viewer: See how your Web page looks in a text-only format.

IBM Home Page Reader: Lets blind or visually impaired users navigate through a Web site using the keyboard. Download a free 30-day trial copy.

Media Access Generator (MAGpie): Allows authors to add captions to three multimedia formats: QuickTime, SMIL, and SAMI. From the National Center for Accessible Media.

With an accessible site you increase your potential audience, avoid lawsuits, and have a site that's responsive to new text-based technologies like Web-enabled mobile phones and PDAs. Surely that's worth a little effort.

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