Web Content Accessibility Guidelines (WCAG) 2.0
By Paul Liddelow, 16 January, 2009
What is WCAG?
The Web Content Accessibility Guidelines (WCAG) is a set ofrecommendations for making Web content more accessible. They are published bythe W3C’s Website Accessibility Initiative (WAI) and were first touted as arecommendation in May 1999. The current standard, released on the 11 December 2008,is WCAG 2.0 and the W3C recommends that Web accessibility policies reference thatdocument.
Whereas WCAG 1.0 was primarily concerned with “...advocatingthe use of W3C Technologies such as HTML and CSS to prepare accessiblewebsites” [http://www.usability.com.au/resources/wcag2/], WCAG 2.0 istechnology neutral. “WCAG 2.0 does not explicitly relate to the use of HTML butis concerned with improving the accessibility of sites regardless of thetechnologies used.” [ibid]
What is accessibility?
Accessibility is defined as “... the degree to which aproduct, system or device is accessible by as many people as possible.” [RuthEllison] Often, accessibility is used in relation to people with disabilities.While people with disabilities are one of the key beneficiaries of accessibledesign, accessibility helps to bring benefits to a wide range of users in manyworking contexts.There are six main types of disability including visual,hearing, mobility, cognitive and learning disabilities, seizure and situationalaccessibility. People are either born with disabilities or acquire it over time(such as visual impairments, which are often acquired due to the agingprocess). Disabilities can be temporary or permanent.
Benefits of accessibility
The benefits of accessible web sites include:
- Can be used by people with physical and cognitive impairments
- Can be used by people in situations where they are unable to use their hands
- Can be used by people who are technically and educationally disadvantaged
- Are more effective for people who live in remote and regional areas
- Are easy for the elderly and novice users to use
- Work with the widest range of browsers and other current internet technologies
- Will migrate to future technologies
Accessibility requirements in Australia:
- Section 24 of the Disability Discrimination Act (1992)
- Australian Government Information Management Office (AGIMO) - From 1 December 2000, all websites were to follow the W3C guidelines to a sufficient extent that they pass recognised tests of accessibility
- The Human Rights and Equal Opportunity Commission's view is that compliance with the W3C WCAG 1.0 guidelines to the Single-A level (Priority 1) is a minimum rather than a desirable outcome.
WCAG 2.0
“Web Content Accessibility Guidelines (WCAG) 2.0 covers awide range of recommendations for making Web content more accessible.” [http://www.w3.org/TR/WCAG20/]By following these guidelines, content will become accessible to a wider rangeof people with disabilities and make content more accessible to people in general.For example, a website completely done in Adobe Flash means that the contentwill be inaccessible to anybody that does not have Flash installed on theirdevice, whether they are disabled or not.
In order to understand how WCAG 2.0 works, there are fourlayers of guidance: Principles, Guidelines, Success Criteria and Sufficient andAdvisory Techniques. At the top are four Principles “... that provide thefoundation for Web accessibility: perceivable,operable, understandable, and robust.” [http://www.w3.org/TR/WCAG20/] Underthe Principles are 12 guidelines that “... provide the basic goals that authorsshould work toward in order to make content more accessible to users withdifferent disabilities.” [ibid] For each Guideline, there is a testable SuccessCriteria with three levels of conformance including: A (lowest), AA and AAA(highest). Lastly, there is Sufficient and Advisory Techniques for each of the guidelinesand success criteria.
“All of these layers of guidance (principles, guidelines,success criteria, and sufficient and advisory techniques) work together toprovide guidance on how to make content more accessible. Authors are encouragedto view and apply all layers that they are able to, including the advisorytechniques, in order to best address the needs of the widest possible range ofusers.” [ibid]
WCAG 2.0 Map
In order to better understand WCAG 2.0, a map has been developedto visualise the concepts. It is available in PDF and is hyperlinked back tothe original WCAG 2.0 content provided by W3C. Please feel free to download a copy and keep as an electronic reference or print it out and put it on yourdesk!
WCAG20Map.pdf