Maximum Accessibility: Making Your Web Site More Usable for Everyone By John M. Slatin,, Sharron Rush
Table of Contents
Chapter 9. Equivalent Alternatives
We began this chapter with the prime directive, the fact that good design requires equivalent alternatives to visual and auditory elements of Web pages. We discuss audio in greater detail in Chapter 13 when we examine multimedia applications, but a few words are necessary here as well.
The Web is an intensely visual medium, and within the past few years it has become increasingly noisy as well. It's important to remember, however, not to depend on sound alone to deliver information. Millions of people who use the Web will not hear those sounds. This may be due to deafness or hearing impairments but may also result from lack of audio speakers (for example, many public computers in libraries and schools do not have speakers). As you incorporate audio elements, be sure to provide text alternatives or other visual equivalents and/or explanations of the information you're delivering.
As we discuss in Chapter 13, how you provide appropriate alternatives will depend on the kind of audio material you're using and the format in which that material is presented. A simple example is an online evaluation in which incorrect answers are greeted with a buzz and correct answers with a bell tone. If at the same time you provide a caption or other visual cue with the same information, you will have provided an acceptable equivalent alternative. For more substantive auditory material such as a recorded news interview or a bit of oral history both WCAG 1.0 and Section 508 require a complete, verbatim transcript of the audio material.
