Accessibility Tips - Series #2
The Pacific ADA Center has produced an Accessible IT quick tip series to benefit educators by enhancing the learning experience of students in all schools. This is the first of twelve articles that will be published on a monthly basis, distributed by post and email, and archived on our web site: http://www.adapacific.org/ To request further materials or information on Accessible IT, please call us on our free Technical Assistance hotline at 1-800-949-4232 or use the contact form on our web site. We hope that you'll find this series valuable.
Overcoming Barriers For the Blind in Curriculum Development
Many people who are legally blind retain some residual vision. Some may be able to see objects with the help of magnification. Others may be able to sense light and dark but little else. Because of the wide range of visual sensitivity found among those who are legally blind, a well-designed interface should assume that the end user has no vision, while allowing that person to make use of whatever residual vision they possess.
To access online material, blind users depend on screen-reading software that digests the contents of the computer screen and sends information to a text-to-speech synthesizer or refreshable Braille display.
Curriculum developers can do much to support screen reading software and to help blind users perceive and understand screen content.
To support screen reading software curriculum developers can:
- Embed descriptive text in graphic images in such a way as to make the text known to screen-reading software. This addresses the problems that can arise when text is rendered as a graphic image and cannot be read by software.
- Assign logical names to controls, even if the name is not visible on the screen. Screen readers can access this information and use it to describe the type and function of the control on the screen.
- Use consistent and predictable screen and dialog layouts.
- Use single column text whenever possible.
- Provide keyboard equivalents for all tools, menus, and dialog boxes.
Since screen readers can only read text (or give names to separately identifiable icons or tools), it is a good idea to:
- Avoid non-text menu items when possible or at least incorporate visible or invisible text cues to accompany these items. Screen readers can see text even if that text is written to the screen invisibly.
- Avoid non-redundant graphic tool bars. Make any tool bar command available in a menu.
Finally, documentation and training materials are always more accessible when:
- Documentation and online help can be understood independent of graphics. Text descriptions should occupy their own space in the program or correspond to graphics, graphical tables, and graphical charts by alphanumeric reference.
- Help dialogs are not displayed in independent pop-up windows.
- Synchronized audio descriptions are available to play alongside animated graphics or movies.
These documents are available in alternate formats, on CD, in large print hard copy and on audiotape, by contacting the Pacific ADA Center. Please call us on our free Technical Assistance hotline at 1-800-949-4232 or use our contact form.