Web Accessibility and Standards
Meeting the Challenges
In 1998, Congress amended the Rehabilitation Act to require Federal agencies to make their electronic and information technology accessible to members of the public with disabilities. Inaccessible technology interferes with an individual’s ability to obtain and use information quickly and easily. Section 508 was enacted to eliminate barriers in information technology, to make available new opportunities for members of the public with disabilities, and to encourage development of technologies that will help achieve these goals. The law applies to all Federal agencies when they develop, procure, maintain, or use electronic and information technology. Under Section 508 (29 U.S.C. 794d), agencies must give members of the public and employees with disabilities access to information that is comparable to the access available to others. It is recommended that you review the laws and regulations listed below to further your understanding about Section 508 and how you can support implementation.
Accessibility Information from Adobe (formerly Macromedia)
Navigation poses a number of issues related to accessibility. Two issues in particular require a consistent approach. The first issue is the use of a skip navigation mechanism. According to Section 508, “a method shall be provided that permits users to skip repetitive navigation links.” A skip navigation mechanism enables screen reader users to avoid listening to every link in the navigation bar on each page. Typically, the designer/developer creates skip navigation by linking a small transparent image at the top of a page to an anchor just before the main content. The alt text description for this image would read “skip to content” or “skip navigation.”
Images benefit from standardization in at least two areas. First, it is helpful to standardize and centrally store alt text for commonly used images across the site. Storing images as library items in Dreamweaver 8 enables designers to add the appropriate alt text only once and use it consistently on all pages. Other designers and developers can then be confident that the correct alt text is there when they place the library item on a page.
Second, a long description should be used for images requiring alt text longer than 50 characters. Multiple strategies are available for adding long descriptions to images. The first is using the longdesc attribute. The longdesc attribute provides a screen reader user with a link to the long description on a separate page.
Cascading Style Sheets (CSS)
Cascading Style Sheets (CSS) offer significant benefits for accessibility. While the use of CSS is not mandated by Section 508, national standards in the U.K. and Canada do require use of CSS.
When site text is formatted with CSS, users can override styles to format text to meet their needs. This allows users with limited vision or colorblindness to change the size or color of text, for example. It is important to note that if HTML is used to format text, this formatting overrides all CSS styles, including user-defined styles; therefore, if the use of CSS for formatting text is standardized, it should be applied consistently across the site.
Flash 8 provides the tools for creating the most exciting and engaging content on the web. Flash Player 8 allows users of assistive technologies to access this content in ways not previously possible, making the best experience on the web available to all. When creating accessible rich media using Flash 8, it is important to pay attention to the screen reader environment. Designers and developers need to provide text equivalents for elements within a movie, and these text equivalents must flow in a logical sequence when read by a screen reader.
A second issue for designers of Flash content is device independence. The Flash movie must support keyboard- and mouse-based interactions. Creating this kind of content may require guidance for novice developers. More information on this and other issues is available at the Macromedia Accessibility Resource Center.
Plug-ins enable browsers to display a particular file format. Each plug-in requires a distinct strategy for accessibility. Under Section 508, the use of plug-ins must comply with standards for software. Similar to standards for web content, the software standards also require that the plug-in function without a mouse.
Use of video and audio content requires a synchronized text alternative, typically in the form of closed captioning. If an organization frequently uses multimedia on its site, it should invest in hardware and software tools that support closed captioning.