WCAG 2.0 is the new set of web accessibility guidelines that was released in 2008 as a recommendation by the W3C. It addresses some issues with the previous WCAG 1.0 guidelines by being technology-agnostic, having clearly testable success criteria focused on user outcomes rather than techniques, and removing outdated requirements. WCAG 2.0 provides more freedom for authors while still ensuring accessibility. It includes 4 principles, 12 guidelines and 61 success criteria to evaluate websites. The transition from WCAG 1.0 involves evaluating sites based on the new success criteria and testing areas that may be different.

1. All change for WCAG 2.0
Patrick H. Lauke / Manchester Digital Development Agency / 24 March 2009
WHAT YOU NEED TO KNOW ABOUT THE NEW ACCESSIBILITY GUIDELINES

2. About me...
● Web Editor for University of Salford
● Web Standards Project (WaSP)
● Author and occasional .net magazine contributor
● NOT an expert?

3. Outline
● Background on WCAG 1.0
● The painful birth of WCAG 2.0
● Overview of the new guidelines
● Next steps for WCAG 1.0 veterans

5. Web Content Accessibility Guidelines 1.0
● www.w3.org/TR/WCAG10
● W3C recommendation 5 May 1999
● 14 guidelines
● 75 checkpoints

6. WCAG 1.0 – problems
● HTML-centric checkpoints, despite separate
techniques document
http://www.w3.org/TR/WAI-WEBCONTENT-TECHS/
● “until user agents” clauses
● Forbids JavaScript and any non-W3C
technologies
● Vague checkpoints

7. WCAG 2.0 – early attempts
● Work began soon after release of WCAG 1.0
● Many iterations, largely under radar of web devs
● Original “Last Call” April 2006

9. To Hell with WCAG 2.0
● Joe Clark's vitriolic style
● A List Apart, 23 May 2006
http://www.alistapart.com/articles/tohellwithwcag2
● Main points of concern:
● Overall size of combined guidelines
● Inscrutable language
● Baseline concept
● Omission of markup validation / standards

10. To Hell with WCAG 2.0
● Generated huge interest from web devs
● Joe Clark started WCAG Samurai project to create
errata for WCAG 1.0
● W3C demoted WCAG 2.0 from Last Call back to
Public Working Draft

12. WCAG 2.0 back on track
● Joe Clark's leaving speech at @media2007 –
confident that WCAG 2.0 heading in right
direction
● Historical aside: my take on amended WCAG 2.0
http://www.webstandards.org/2007/06/11/review-wcag2-may2007-working-draft/
● Nonetheless released WCAG Samurai Errata
http://wcagsamurai.org/

14. Web Content Accessibility Guidelines 2.0
● www.w3.org/TR/WCAG20
● W3C recommendation 11 December 2008

15. WCAG 2.0 suite of documents

16. WCAG 2.0 suite of documents
● Web Content Accessibility Guidelines 2.0
[normative]
● How to Meet WCAG 2.0 [informative]
● Understanding WCAG 2.0 [informative]
● Techniques for WCAG 2.0 [informative]
● http://www.w3.org/WAI/intro/wcag20

17. Web Content Accessibility Guidelines 2.0
● 4 general principles
● 12 guidelines
● 61 success criteria

18. WCAG 2.0 principles
A website should be...
● Perceivable
● Operable
● Usable
● Robust

19. WCAG 2.0 improvements
● Principles, guidelines and success criteria are
technology-agnostic

20. WCAG 1.0 examples
● “Guideline 5. Create tables that transform
gracefully”
● “5.3 Do not use tables for layout unless the
table makes sense when linearized.”
● “Note. Once user agents support style sheet positioning,
tables should not be used for layout.”
● So what happens with CSS positioning that breaks
linear flow?

21. WCAG 2.0 examples
● “Guideline 1.3 Adaptable: Create content that can be presented
in different ways (for example simpler layout) without losing
information or structure.”
● “1.3.2 Meaningful Sequence: When the sequence in which
content is presented affects its meaning, a correct
reading sequence can be programmatically
determined.”

22. WCAG 2.0 improvements
● WCAG 1.0 “Guideline 11. Use W3C technologies
and guidelines”
● “Where it is not possible to use a W3C technology, or doing
so results in material that does not transform gracefully,
provide an alternative version of the content that is
accessible.”
● WCAG 2.0 can be applied to W3C and non-W3C
technologies (as long as they're accessibility-
supported)

23. WCAG 2.0 improvements
● Accessibility-supported technologies
● supported by users' assistive technology
● technology must have accessibility-supported
user agents that are available to users

24. WCAG 2.0 accessibility-supported
● You can use PDF, Flash, even JavaScript
● JavaScript and WAI-ARIA
http://www.w3.org/TR/wai-aria/
● Even if a technology isn't fully accessibility-
supported, as long as you use the supported bits
● Worst case provide fallback that is supported

25. WCAG 2.0 improvements
● Removes all “until user agents...” clauses

26. WCAG 1.0 example
● “Guideline 10. Use interim solutions.”
● “10.4 Until user agents handle empty controls correctly, include
default, place-holding characters in edit boxes and text areas.”

27. WCAG 2.0 improvements
● Each success criterion is more easily testable
● Success criteria give clearer guidance than WCAG
1.0 checkpoints

28. WCAG 1.0 example
● “Guideline 2. Don't rely on color alone.”
● “2.2 Ensure that foreground and background color
combinations provide sufficient contrast when viewed
by someone having color deficits or when viewed on a
black and white screen.”
● What exactly is “sufficient”?

29. WCAG 2.0 example
● “Guideline 1.4 Distinguishable: Make it easier for users to see and
hear content including separating foreground from background.”
● AA “1.4.3 Contrast (Minimum): The visual presentation of
text and images of text has a contrast ratio of at least
4.5:1”
● “Large Text: Large-scale text and images of large-scale text
have a contrast ratio of at least 3:1”
● AAA “1.4.6 Contrast (Enhanced): The visual presentation of
text and images of text has a contrast ratio of at least 7:1”
● “Large Text: Large-scale text and images of large-scale text
have a contrast ratio of at least 4.5:1”

30. WCAG 2.0 improvements
● As a result of clearer, testable SCs some things
are allowed that previously weren't

31. WCAG 1.0 example
● “Guideline 7. Ensure user control of time-sensitive
content changes.”
● “7.1 Until user agents allow users to control flickering, avoid
causing the screen to flicker.”
● “7.2 Until user agents allow users to control blinking, avoid
causing content to blink[...]”

32. WCAG 2.0 example
● “Guideline 2.3 Seizures: Do not design content in a
way that is known to cause seizures”
● “2.3.1 Three Flashes or Below Threshold: Web pages do
not contain anything that flashes more than three
times in any one second period, or the flash is
below the general flash and red flash thresholds.”

33. WCAG 2.0 improvements
● Success criteria focus on the outcomes, not how
they're achieved

34. WCAG 1.0 example
● “Guideline 9. Design for device-independence.”
● “9.5 Provide keyboard shortcuts to important links
(including those in client-side image maps), form controls,
and groups of form controls.”
● “For example, in HTML, specify shortcuts via the
"accesskey" attribute.”

35. WCAG 2.0 example
● “Guideline 2.1 Keyboard Accessible: Make all
functionality available from a keyboard.“
● “2.1.1 Keyboard: All functionality of the content is operable
through a keyboard interface [...]”

36. WCAG 2.0 improvements
● Talks about mechanisms
● “process or technique for achieving a result”

37. WCAG 2.0 mechanism example
● “Guideline 2.4 Navigable: Provide ways to help users navigate, find
content, and determine where they are.”
● “2.4.1 Bypass Blocks: A mechanism is available to bypass
blocks of content that are repeated on multiple Web
pages.”
● Does this mandate skip links?

38. WCAG 2.0 mechanism example
● Looking at “How to meet WCAG 2.0”, skip links only
one of a few techniques mentioned
● Sufficient Techniques for 2.4.1 – Bypass Blocks:
● Creating links to skip blocks of repeated material
● Grouping blocks of repeated material in a way that can be
skipped
● Advisory Techniques for 2.4.1 – Bypass Blocks
● [...]
● C6: Positioning content based on structural markup

39. WCAG 2.0 techniques
● Techniques cover general technologies: HTML,
CSS, JavaScript, WAI-ARIA
● Sufficient and advisory techniques
● Techniques are informative, not normative
● List of techniques is not exhaustive – invent your
own as long as success criteria are fulfilled

40. WCAG 2.0 conformance
● WCAG 1.0 had duality of priority 1,2,3 that
mapped to levels A, AA, AAA
● WCAG 2.0 just uses A, AA, AAA model for both SCs
and conformance levels

41. WCAG 2.0 conformance
● Applies to full pages
● Complete processes
● Only accessibility-supported techs are relied on
● Non-interference (when adding non-accessibility-
supported technologies)
● You can conform without a conformance claim

42. WCAG 2.0 partial conformance
● 3rd
party content (UGC, feeds, etc)
● Use of languages/technologies without accessibility-
support (future-proofing?)

43. Transition from WCAG 1.0 to WCAG 2.0
● Needs of users with disabilities hasn't changed
● Technology that they use has
● If your site accessible under WCAG 1.0, shouldn't be
too far off WCAG 2.0

44. Transition from WCAG 1.0 to WCAG 2.0
● How WCAG 1.0 differs from WCAG 2.0
http://www.w3.org/WAI/WCAG20/from10/diff.php
● Comparison WCAG 1.0 checkpoints to WCAG 2.0
http://www.w3.org/WAI/WCAG20/from10/comparison/
● How to update your site from WCAG 1.0 to 2.0
http://www.w3.org/WAI/WCAG20/from10/websites.html

45. Transition from WCAG 1.0 to WCAG 2.0
● Evaluate your site based on WCAG 2.0 SCs
● Many 1.0 checkpoints map to 2.0 SCs
● Are there 1.0 requirements that have been lifted?
● Test more specific 2.0 SCs

46. Getting started with WCAG 2.0
● WebAIM's unofficial checklist
http://webaim.org/standards/wcag/checklist

48. Getting started with WCAG 2.0
● For a “one-stop shop” overview, customisable
WCAG 2.0 quick reference
http://www.w3.org/WAI/WCAG20/quickref/

50. Recap on WCAG 2.0
● Technology-agnostic – applicable to more
present and future technologies
● Clearly testable Success Criteria
● Focussed on outcome for users, not techniques
● Removes outdated requirements from 1.0
● Overall allows authors more freedom

51. Thanks
Patrick H. Lauke
http://www.splintered.co.uk