Web Accessibility at the University of California

Technical Topics

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The technical challenges that Web developers encounter when creating accessible Web sites are numerous and change constantly as technologies evolve. Many resources are available, though, through which Web developers may learn more about, and engage in discussion about, the particular challenges they may be encountering.

• Discussion Forums: WebAIM offers several online discussion forums, which are a good avenue for getting more information about how to approach technical challenges.
• Articles: A series of articles on various technical topics as they relate to Web accessibility may be found at the magazine, A List Apart.
• UC E-mail List: UC employees may join a Universitywide e-mail discussion list of technical and other UC personnel interested in IT accessibility issues. To join the list (accessible-l@ucop.edu), send an e-mail to .

Information about selected technical challenges is provided below.

AJAX (More information about AJAX on WebAIM site)
JavaScript support in screen readers is incomplete, rendering most JavaScript-dependent applications unusable. Furthermore, the dynamic nature of data and interface changes made using AJAX are not registered by screen readers.

• A Sitepoint article, "AJAX and Screenreaders: When Can It Work?" offers examples and challenges.
• Max Kiesler discusses how to make AJAX applications accessible.
• Jeremy Keith writes "Hijax: Progressive Enhancement with AJAX."

PDFs (More information about PDFs on WebAIM site)
Current versions of Adobe create accessible pdf files. Information from WebAIM provides a good discussion about Adobe's accessibility features. Web developers should be aware that people using Adobe Reader 5 or earlier will not have access to the current Adobe accessibility features. Adobe Reader 8 will ask the user if they want to "OCR" scanned documents that are images, so that a screen reader is able to access it. However the OCR version may not always be perfect, as it depends on the quality of the scanned image which is the source. The user can save the OCR version for later use. Files converted to pdf from a .doc, .txt., .rtf and other document standards should be fully accessible after conversion as long as they do not contain images.

Flash
Flash features can increase accessibility (for example, through scalability, presentation of audio content, and keyboard accessibility). But developers must employ techniques to avoid the same accessibility problems found with HTML. WebAIM has a good article on the subject, "Creating Accessible Macromedia Flash Content."

Maps
Developers of accessible sites need to ensure that maps are useful for visually impaired people. A List Apart offers an article on methods for creating accessible maps that separate the text-based map data from the visual design.