1. Web Content Accessibility Leila Styer Washington State University CAHNRS/Computer Resource Unit rev. November 2006

2. What is Web Accessibility?

3. Web accessibility means that people with disabilities can use the Web. More specifically, Web accessibility means that people with disabilities can perceive, understand, navigate, and interact with the Web, and that they can contribute to the Web. Web accessibility also benefits others, including older people with changing abilities due to aging.

4. Why is Accessibility So Important? The Web is an increasingly important resource in many aspects of life: education, employment, government, commerce, health care, recreation, and more. It is essential that the Web be accessible in order to provide equal access and equal opportunity to people with disabilities. An accessible Web can also help people with disabilities more actively participate in society.

5. Legal Obligations Section 504 of the 1973 Rehabilitation Act 1990 Americans with Disabilities Act Both state that “No otherwise qualified individual with a disability shall, solely by reason of his/her disability, be excluded from the participation in, be denied the benefits of, or be subjected to discrimination under any program or activity of a public entity.” http://www.w3.org/WAI/Policy/#US US Policies Relating to Web Accessibility

6. Making the Web Site Accessible Making a Web site accessible can be simple or complex, depending on many factors such as the type of content, the size and complexity of the site, and the development tools and environment.

7. Web Content Web "content" generally refers to the information in a Web page or Web application, including text, images, forms, sounds, and such. Web Content Accessibility Guidelines (WCAG) WCAG Versions: 2.0

8. Essential Components of Web Accessibility: It is essential that several different components of Web development and interaction work together in order for the Web to be accessible to people with disabilities. These components include: content Web browsers, media players assistive technology users developers authoring tools evaluation tools

9. How the Components Relate People ("users") use Web browsers, media players, assistive technologies, or other "user agents" to get and interact with the content. Web developers usually use authoring tools and evaluation tools to create Web content.

10. Interdependencies Between Components: There are significant interdependencies between the components; that is, the components must work together in order for the Web to be accessible. For example, for alternative text on images: Technical specifications WAI guidelines Developers Authoring tools Evaluation tools User agents Assistive technologies Users

11. The Implementation Cycle When accessibility features are effectively implemented in one component, the other components are more likely to implement them.

12. When One Component is Weak

13. If one component has poor accessibility support, sometimes other components can compensate through "work-around" that require much more effort and are not good for accessibility overall. For example, developers can do more work to compensate for some lack of accessibility support in authoring tools; for example, coding markup directly instead of through a tool users can do more work to compensate for some lack of accessibility support in browsers, media players, and assistive technology and lack of accessibility of content; for example, using different browsers or assistive technologies to overcome different accessibility issues

14. Guidelines for Different Components: Authoring Tool Accessibility Guidelines (ATAG) addresses authoring toolsAuthoring Tool Accessibility Guidelines (ATAG) Web Content Accessibility Guidelines (WCAG) addresses Web content, and is used by developers, authoring tools, and accessibility evaluation toolsWeb Content Accessibility Guidelines (WCAG) User Agent Accessibility Guidelines (UAAG) addresses Web browsers and media players, including some aspects of assistive technologiesUser Agent Accessibility Guidelines (UAAG) The World Wide Web Consortium (W3C) Web Accessibility Initiative (WAI) develops Web accessibility guidelines for the different components:W3CWAI W3C technical specifications (HTML, XML, CSS, SVG, SMIL, etc.)W3C technical specifications WAI guidelines are based on the fundamental technical specifications of the Web, and are developed in coordination with:

16. Tips to Make Accessible Web Sites The following ten "Quick Tips" summarize key concepts of accessible Web design. These tips are not complete guidelines; they are only excerpts of concepts from the Web Content Accessibility Guidelines 2.0 (WCAG 2.0).WCAG 2.0 Images & animations Image maps Multimedia Hypertext links Page organization Graphs & charts Scripts, applets, & plug-ins Frames Tables Check your work

17. WCAG Versions: 2.0 Principle 1: Content must be perceivable Principle 2: Interface components in the content must be operable Principle 3: Content and controls must be understandable Principle 4: Content should be robust enough to work with current and future user agents (including assistive technologies)

18. Principle 1 Guideline 1.1 Provide text alternatives for all non-text content Guideline 1.2 Provide synchronized alternatives for multimedia Guideline 1.3 Ensure that information and structure can be separated from presentation Guideline 1.4 Make it easy to distinguish foreground information from its background http://www.w3.org/TR/WCAG20/guidelines.html

19. Provide Text Alternatives for all non-text content This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ASCII art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and video.

20. Provide synchronized alternatives for multimedia Captions are provided for prerecorded multimedia Audio description of video

21. Ensure that information and structure can be separated from presentation Information and relationships conveyed through presentation can be programmatically determined, and notification of changes to these is available to user agents, including assistive technologies. Any Information that is conveyed by color is also visually evident without color When the sequence of the content affects its meaning, that sequence can be programmatically determined.

22. Make it easy to distinguish foreground information from its background Text or diagrams, and their background, have a luminosity contrast ratio of at least 5:1 A Mechanism is available to turn off background audio that plays automatically, without requiring the user to turn off all audio.

23. Principle 2 Guideline 2.1 Make all functionality operable via a keyboard interface Guideline 2.2 Allow users to control time limits on their reading or interaction Guideline 2.3 Allow users to avoid content that could cause seizures due to photosensitivity Guideline 2.4 Provide mechanisms to help users find content, orient themselves within it, and navigate through it Guideline 2.5 Help users avoid mistakes and make it easy to correct mistakes that do occur

24. Make all functionality operable via a keyboard interface All functionality of the content is operable in a non-time-dependent manner through a keyboard interface, except where the task requires analog, time-dependent input.

25. Allow users to control time limits on their reading or interaction For each time-out that is a function of the content, at least one of the following is true: the user is allowed to deactivate the time-out; or the user is allowed to adjust the time-out over a wide range that is at least ten times the length of the default setting; or the user is warned before time expires and given at least 20 seconds to extend the time-out with a simple action (for example, "hit any key"), and the user is allowed to extend the timeout at least ten times; or the time-out is an important part of a real-time event (for example, an auction), and no alternative to the time-out is possible; or the time-out is part of an activity where timing is essential (for example, competitive gaming or time-based testing) and time limits can not be extended further without invalidating the activity.

26. Allow users to avoid content that could cause seizures due to photosensitivity Content does not violate the general flash threshold or the red flash threshold.

27. Provide mechanisms to help users find content, orient themselves within it, and navigate through it A mechanism is available to bypass blocks of content that are repeated on multiple web units.

28. Help users avoid mistakes and make it easy to correct mistakes that do occur If an input error is detected, the error is identified and described to the user in text.

29. Principle 3 Guideline 3.1 Make text content readable and understandable. Guideline 3.2 Make the placement and functionality of content predictable.

30. Make text content readable and understandable The primary natural language or languages of the web unit can not programmatically determined.

31. Make the placement and functionality of content predictable When any component receives focus, it does not cause a change of context. Changing the setting of any form control or field does not automatically cause a change of context, unless the authored unit contains instructions before the control that describe the behavior.

32. Principle 4 Guideline 4.1 Support compatibility with current and future user agents (including assistive technologies) Guideline 4.2 Ensure that content is accessible or provide an accessible alternative

33. Support compatibility with current and future user agents (including assistive technologies) Web units or authored components can be parsed unambiguously, and the relationships in the resulting data structure are also unambiguous. For all user interface components, the name and role can be programmatically determined, values that can be set by the user can be programmatically set, and notification of changes to these items is available to user agents, including assistive technologies.

34. Any Questions?

35. More Resources HTML Writers Guild  http://www.hwg.org/ Visually Impaired  http://www.textmatters.com/ Hints for Accessible Websites  http://www.rnib.org.uk/ World Wide Web Consortium  http://www.w3.org/TR/WCAG20/ TRACE Center Overview  http://trace.wisc.edu/world/java/java.htm National Center for Accessible Media  http://www.wgbh.org/wgbh/pages/ncam/

36. Thank You Leila M. Styer CAHNRS - Computer Resource Unit Washington State University Hulbert Hall 301H Pullman, Washington 99164-6244 (509)335-2967 styer@wsu.edu