Distance Education Accessibility Guidelines
In updating these guidelines, it was essential to communicate them in the context of standards that exist in the public arena. As with the 1999 Distance Education: Access Guidelines for Students with Disabilities
, the Task Force followed the principles developed by the World Wide Web Consortium (W3C). In this update, Web Content Accessibility Guidelines (WCAG) 2.0 specifically were utilized.
The W3C is an international community. Member organizations, a full-time staff, and the public worked together under a clear and effective consensus-based process with a goal of providing a shared standard for Web content accessibility that meets the needs of individuals, organizations, and governments internationally.
Web Content Accessibility Guidelines 2.0 provide definitions and requirements essential to making web content accessible. Several layers of guidance are offered, including overall principles
, general guidelines
, testable success criteria
and a rich collection of sufficient techniques
, advisory techniques
, and documented common failures
with examples, resource links and code.
The use of WCAG 2.0 will make content accessible to a wider range of disabilities, including blindness and low vision, deafness and hearing loss, learning disabilities, cognitive limitations, limited movement, speech disabilities, photosensitivity and combinations of these. Following these Guidelines will also make Web content more functional to users in general.
Under each of the principles are Guidelines and Success Criteria that help to address these principles for people with disabilities by defining conformance to the WCAG 2.0 Guidelines. A Success Criterion is a testable statement that will be either true or false when applied to specific Web content. "Understanding WCAG 2.0" provides detailed information, including intent, the key terms that are used in the Success Criterion, and how the Success Criteria in WCAG 2.0 help people with different types of disabilities. WCAG 2.0 only includes those Guidelines that address issues that significantly block access or interfere with access to the Web for people with disabilities.
There are four principles that provide the foundation for Web accessibility: perceivable
, and robust
. The Guidelines and Success Criteria are organized around the following four principles, which lay the foundation necessary for anyone to access and use Web content. Anyone who wants to use the Web must have content that is:
- Perceivable: Information and user interface components must be presentable to users in ways they have the ability to comprehend (it can't be invisible to all of their senses), e.g.:
- Provide text alternatives for non-text content.
- Provide captions and alternatives for audio and video content.
- Make content adaptable; and make it available to assistive technologies.
- Use sufficient contrast to make things easy to see and hear.
- Operable: User interface components and navigation cannot require interaction that a user is unable to perform, e.g.:
- Make all functionality keyboard accessible.
- Give users enough time to read and use content.
- Do not use content that may cause seizures.
- Help users navigate and find content.
- Understandable: Information and the operation
of user interface cannot be beyond the users' comprehension, e.g.:
- Make text readable and understandable.
- Make content appear and operate in predictable ways.
- Help users avoid and correct mistakes.
- Robust: Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies, e.g.:
- Maximize compatibility with current and future technologies.
If any of the four principles are not met, users with disabilities will not be able to use the Web.