Provide Effective Internationalization and Accessibility 643

Step 10: Provide Effective Internationalization and Accessibility 643

Video — include one or more of the following in both a textual and audio format: — A transcript. — A description.

• For lengthy transcripts or descriptions, provide a link to a separate page.

Image maps: — Provide equivalent text menus.

Animation: — Provide an option to display in a nonanimated presentation mode.

Synchronize multimedia elements.

Plug-ins and applets: — Use sparingly.

Test for accessibility.

For online forms that cannot be read by screen utilities, provide alternate methods of communication.

If accessibility cannot be accomplished in any other way, provide a text-only page with equivalent information and functionality. — Follow the guidelines set by the World Wide Web Consortium for accessibility of

Web content. — If being designed for the United States Government, ensure that the require- ments of Section 508 of the Rehabilitation Act are met.

In addition to the previously described guidelines, Web page design requires addi- tional accessibility considerations. A few of these guidelines mirror good Web page design in general. A portion of these guidelines are derived from Head (1999). In gen- eral, text equivalents should be provided for all non-text elements.

Pages.

A simple and consistent layout is important for people with visual impair- ments. When using screen readers, a page can be more quickly navigated. Important information at the top of a page also aids screen readers because the reader reads left-to-right and top-to-bottom. Simple, contrasting backgrounds allow the information to be more easily read.

When a navigation bar is located at the top or left side of a page, a user using speech synthesis must listen to all navigation links before arriving at the main page content. This can become especially cumbersome if the links are consis- tently repeated on successive pages. (A sighted user can easily ignore the links.) To bypass these links, and other elements such as tables of contents, provide a “Skip to Main Content” link attached to an unimportant image at the beginning of each page. The user can activate this link when it is presented, and the focus will move directly to the start of the page’s content. (The user always has the choice to pass over this link and continue through the navigation links.)

Structure articles with two or three levels of headings. Nested headings facili- tate access using screen-review utilities. All sentences, headings, and list items should end with punctuation so the screen reader can signal a break to the user. Screen readers do not recognize physical separation or bullets. Provide frame titles that help to easily identify the frame. This aids navigation, and proper ori-

644 Part 2: The User Interface Design Process

and styles, colors, graphical attributes, and volume so the user can make adjust- ments to satisfy his or her needs. When a font size adjustment is made, the page should automatically resize to match the adjustment. Blinking or constantly changing elements should not be used so that people with visual or seizure impairments are not disturbed.

Controls. Buttons should be large, making them easy targets. People with physical movement disabilities will find them much easier to select. Links. Provide fully descriptive link headings so people using screen readers will fully understand the link’s meaning. The link title should aid decision-making. Separate consecutive links with a dividing character so that a clear break in con- tent can be ascertained by the screen reader.

Tables, frames, and columns. These elements should be used sparingly because the majority of screen readers in their left-to-right movement will not distinguish separate cells of information in their translation. If tables are used, provide alter- nate ways to access their content because of the difficulty sight-impaired users have in navigating within a table using screen-review utilities. If frames are used, provide frame titles to facilitate frame identification, orientation, and navigation.

Images . Screen-review utilities cannot reveal images to visually impaired users. Therefore it is important to associate text with active images, particularly links or command buttons. When an image is not active, whether to provide associated text must be determined based upon the situation. The visually impaired user will not be able to ignore this audio text as a sighted user can if text is included. Include, then, short textual description for all important images. To include a lengthy text description, provide a link to a separate page that contains a com- plete description.

Audio . For hearing-impaired users, include one of the following textual alterna- tives. For short audio pieces, provide a caption or small pop-up window describing the audio. For longer audio, consider providing a textual transcript, an exact word-for-word version of the audio. Give the user the choice of reading the tran- script, listening to the audio, or both reading and listening. Also consider a tex- tual description, a longer and more extensive audio presentation than a transcript. This kind of description can be both subjective and artistic, depending on the needs of the user. Governmental legislation in some countries requires that these textual alternatives be synchronized with the audio presentation. For a very lengthy transcript or description, consider providing a link to a separate page containing a complete transcript or description.

Video . For all video content include a transcript or description in both a textual and audio format. As previously mentioned, a transcript is an exact word-for-word version of the video. A description, also both subjective and artistic, is a longer and more extensive summarization of the video. It generally includes actions, set- tings, body language, and scene changes necessary to fully understand the video. Again, governmental legislation in some countries requires that these alterna- tives be synchronized with the video presentation.

Image maps . For content embedded in image maps provide equivalent textual