WCAG 2.0 uses the UAAG definition (instance 2) of 'user agent.' WCAG 2.0 assumes that user agents support all the technologies in a defined baseline. The definition of user agent support derives from UAAG. There is significant overlap between presumed functionality within user agents and perception, operability, understandability, and robustness of the content.

Note: WCAG column lists Principles (Principle x) , Guidelines (Guideline x.x), and Success Criteria (Level x ...) each in a seperate cell.

JR:

CMN said: "We should go through WCAG and UAAG looking for places where there is overlap, and ask them to relax content requirements where there is "sufficient" support for the relevant UAAG checkpoint in the baseline, to take account of that support. (We need to define sufficient...) "

JR wonders: Maybe there are 3 sub-groups:

 

WCAG 2.0 Guidelines UAAG Checkpoints
 

Almost all need:

  • 8.1 Implement accessibility features (P1)Supports WCAG

 

Principle 1: Content must be perceivable.
Guideline 1.1 Provide text alternatives for all non-text content
  • 2.1 Render content according to specification (P1)

Level 1 Success Criteria for Guideline 1.1

1.1.1 For all non-text content, one of the following is true: [How to meet 1.1.1]

  • 2.1 Render content according to specification (P1)Supports WCAG
  • 2.5 Make captions, transcripts, audio descriptions available (P1)Supports WCAG
Guideline 1.2 Provide synchronized alternatives for multimedia
  • 2.5 Make captions, transcripts, audio descriptions available (P1)
  • 2.6 Respect synchronization cues (P1)4.4 Slow multimedia (P1)
  • 4.5 Start, stop, pause, and navigate multimedia (P1)
  • 4.6 Do not obscure captions (P1)

Level 1 Success Criteria for Guideline 1.2

1.2.1 Captions are provided for prerecorded multimedia. [How to meet 1.2.1]

  • 2.5 Make captions, transcripts, audio descriptions available (P1)Supports WCAG
  • 2.6 Respect synchronization cues (P1)Supports WCAG
  • 4.4 Slow multimedia (P1)Bonus for WCAG
  • 4.5 Start, stop, pause, and navigate multimedia (P1)Bonus for WCAG
  • 4.6 Do not obscure captions (P1)Supports WCAG

Level 2 Success Criteria for Guideline 1.2

1.2.3 Audio descriptions of video are provided for prerecorded multimedia. [How to meet 1.2.3]

1.2.4 Captions are provided for live multimedia. [How to meet 1.2.4]

  • 2.5 Make captions, transcripts, audio descriptions available (P1)Supports WCAG
  • 2.6 Respect synchronization cues (P1)Supports WCAG
  • 4.4 Slow multimedia (P1)Bonus for WCAG
  • 4.5 Start, stop, pause, and navigate multimedia (P1)Bonus for WCAG

Level 3 Success Criteria for Guideline 1.2

1.2.6 Extended audio descriptions of video are provided for prerecorded multimedia. [How to meet 1.2.6]

1.2.7 For prerecorded multimedia, a full multimedia text alternative including any interaction is provided. [How to meet 1.2.7]

  • 2.6 Respect synchronization cues (P1)Supports WCAG
  • 2.5 Make captions, transcripts, audio descriptions available (P1)Supports WCAG
  • 4.4 Slow multimedia (P1)Bonus for WCAG
  • Extended audio descs are not mentionned in UA but needed for Supports WCAG
Guideline 1.3 Ensure that information and structure can be separated from presentation
  • 9.9 Allow structured navigation (P2)
  • 6.4 Programmatic access to information about rendered content (P1)

Level 1 Success Criteria for Guideline 1.3

1.3.1 Information and relationships conveyed through presentation can be programmatically determined and notification of changes to these is available to user agents, including assistive technologies. [How to meet 1.3.1]

1.3.2 Any information that is conveyed by color is visually evident without color. [How to meet 1.3.2]

1.3.3 When the sequence of the content affects its meaning, that sequence can be programmatically determined. [How to meet 1.3.3]

  • 6.4 Programmatic access to information about rendered content (P1)

Level 2 Success Criteria for Guideline 1.3

1.3.4 Information that is conveyed by variations in presentation of text is also conveyed in text or the variations in presentation of text can be programmatically determined. [How to meet 1.3.4]

1.3.5 Information required to understand and operate content does not rely on shape, size, visual location, or orientation of components. [How to meet 1.3.5]

 
Guideline 1.4 Make it easy to distinguish foreground information from its background
  • 3.1 Toggle background images (P1)
  • 4.3 Configure text colors (P1)
  • 4.8 Independent volume control (P1)

Level 1 Success Criteria for Guideline 1.4

(No level 1 success criteria for this guideline.)

 

Level 2 Success Criteria for Guideline 1.4

1.4.1 Text or diagrams, and their background, have a luminosity contrast ratio of at least 5:1. [How to meet 1.4.1]

1.4.2 A mechanism is available to turn off background audio that plays automatically, without requiring the user to turn off all audio. [How to meet 1.4.2]

  • 4.3 Configure text colors (P1) Replaces WCAG for text in 1.4.1
  • 4.8 Independent volume control (P1) Replaces WCAG 1.4.2?
Principle 2: Interface components in the content must be operable

Level 3 Success Criteria for Guideline 1.4

1.4.3 Text or diagrams, and their background, have a luminosity contrast ratio of at least 10:1. [How to meet 1.4.3]

1.4.4 Audio content does not contain background sounds, background sounds can be turned off, or background sounds are at least 20 decibels lower than the foreground audio content, with the exception of occasional sound effects. [How to meet 1.4.4]

Note: A 20 decibel difference in sound level is roughly 4 times quieter (or louder). Background sound that meets this requirement will be approximately four times (4x) quieter than the foreground audio content.

  
Guideline 2.1 Make all functionality operable via a keyboard interface
  • 1.1 Full keyboard access (P1) Supports WCAG
  • 2.4 Allow time-independent interaction (P1) Replaces WCAG for time limits under UA control

Level 1 Success Criteria for Guideline 2.1

2.1.1 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. [How to meet 2.1.1]

Note: This does not preclude and should not discourage the support of other input methods (such as a mouse) in addition to keyboard operation.
  • 1.1 Full keyboard access (P1)
  • 2.4 Allow time-independent interaction (P1)
Guideline 2.2 Allow users to control time limits on their reading or interaction
  • 2.4 Allow time-independent interaction (P1)
  • 3.3 Toggle animated or blinking text (P1)
  • 3.5 Toggle automatic content retrieval (P1)
  • 5.1 No automatic content focus change (P2)
  • 11.5 Default input configuration (P2)

Level 1 Success Criteria for Guideline 2.2

2.2.1 For each time-out that is a function of the content, at least one of the following is true: [How to meet 2.2.1]

  • the user is allowed to deactivate the time-out; or
  • the user is allowed to adjust the time-out over a wide range which 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 10 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.
  • 2.4 Allow time-independent interaction (P1)
  • 3.5 Toggle automatic content retrieval (P1)
  • 5.1 No automatic content focus change (P2)
  • 11.5 Default input configuration (P2)

Level 2 Success Criteria for Guideline 2.2

2.2.3 Content can be paused by the user unless the timing or movement is part of an activity where timing or movement is essential. [How to meet 2.2.3]

  • 2.4 Allow time-independent interaction (P1)
  • 3.3 Toggle animated or blinking text (P1) Replaces WCAG 2.2.2
  • 11.5 Default input configuration (P2)

Level 3 Success Criteria for Guideline 2.2

2.2.4 Except for real-time events, timing is not an essential part of the event or activity presented by the content. [How to meet 2.2.4]

2.2.5 Interruptions, such as updated content, can be postponed or suppressed by the user, except interruptions involving an emergency. [How to meet 2.2.5]

2.2.6 When an authenticated session expires, the user can continue the activity without loss of data after re-authenticating. [How to meet 2.2.6]

  • 2.4 Allow time-independent interaction (P1)
  • 11.5 Default input configuration (P2)
Guideline 2.3 Allow users to avoid content that could cause seizures due to photosensitivity
  • 3.2 Toggle audio, video, animated images (P1) Replaces WCAG
  • 3.3 Toggle animated or blinking text (P1) Replaces WCAG

Level 1 Success Criteria for Guideline 2.3

2.3.1 Content does not violate the general flash threshold or the red flash threshold. [How to meet 2.3.1]

  • 3.2 Toggle audio, video, animated images (P1) Replaces WCAG
  • 3.3 Toggle animated or blinking text (P1) Replaces WCAG
Guideline 2.4 Provide mechanisms to help users find content, orient themselves within it, and navigate through it

Level 1 Success Criteria for Guideline 2.4
  • 9.9 Allow structured navigation (P2)
  • 10.4 Provide outline view (P2)
  • 11.5 Default input configuration (P2)

Level 2 Success Criteria for Guideline 2.4
  • 9.9 Allow structured navigation (P2)
  • 10.5 Provide link information (P3)
  • 6.4 Programmatic access to information about rendered content (P1)

Level 3 Success Criteria for Guideline 2.4

  • 6.4 Programmatic access to information about rendered content (P1)
  • 10.2 Highlight selection, content focus, enabled elements, visited links (P1)
  • 10.5 Provide link information (P3)
  • 10.6 Highlight current viewport (P1)
Guideline 2.5 Help users avoid mistakes and make it easy to correct mistakes that do occur
  • 6.5 Programmatic operation of user agent user interface (P1)
  • 6.6 Programmatic notification of changes (P1)
  • 5.5 Confirm form submission (P2)

Level 1 Success Criteria for Guideline 2.5

2.5.1 If an input error is detected, the error is identified and described to the user in text. [How to meet 2.5.1]

  • 6.5 Programmatic operation of user agent user interface (P1)
  • 6.6 Programmatic notification of changes (P1)
  • 5.5 Confirm form submission (P2)

Level 2 Success Criteria for Guideline 2.5

2.5.2 If an input error is detected and suggestions for correction are known and can be provided without jeopardizing the security or purpose of the content, the suggestions are provided to the user. [How to meet 2.5.2]

2.5.3 For forms that cause legal or financial transactions to occur, that modify or delete data in data storage systems, or that submit test responses, at least one of the following is true: [How to meet 2.5.3]

  1. Actions are reversible.
  2. Actions are checked for input errors before going on to the next step in the process.
  3. The user is able to review and confirm or correct information before submitting it.
  • 6.5 Programmatic operation of user agent user interface (P1)
  • 6.6 Programmatic notification of changes (P1)
  • 5.5 Confirm form submission (P2)

Level 3 Success Criteria for Guideline 2.5

2.5.4 Context-sensitive help is available for text input. [How to meet 2.5.4]

 
Principle 3: Content and controls must be understandable
Guideline 3.1 Make text content readable and understandable.
  • 6.1 Programmatic access to HTML/XML infoset (P1)

Level 1 Success Criteria for Guideline 3.1

3.1.1 The primary natural language or languages of the Web unit can be programmatically determined. [How to meet 3.1.1]

  • 6.1 Programmatic access to HTML/XML infoset (P1)

Level 2 Success Criteria for Guideline 3.1

3.1.2 The natural language of each passage or phrase in the Web unit can be programmatically determined. [How to meet 3.1.2]

Note: This requirement does not apply to individual words or phrases that have become part of the primary language of the content.
  • 6.1 Programmatic access to HTML/XML infoset (P1)

Level 3 Success Criteria for Guideline 3.1

3.1.3 A mechanism is available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon. [How to meet 3.1.3]

3.1.4 A mechanism for finding the expanded form of abbreviations is available. [How to meet 3.1.4]

3.1.5 When text requires reading ability more advanced than the lower secondary education level, supplemental content is available that does not require reading ability more advanced than the lower secondary education level. [How to meet 3.1.5]

3.1.6 A mechanism is available for identifying specific pronunciation of words where meaning cannot be determined without pronunciation. [How to meet 3.1.6]

 
Guideline 3.2 Make the placement and functionality of content predictable.

Level 1 Success Criteria for Guideline 3.2

3.2.1 When any component receives focus, it does not cause a change of context. [How to meet 3.2.1]

3.2.2 Changing the setting of any form control or field does not automatically cause a change of context (beyond moving to the next field in tab order) unless the authored unit contains instructions before the control that describe the behavior. [How to meet 3.2.2]

  • 9.3 Move content focus (P1)
  • 5.1 No automatic content focus change (P2)
  • 9.5 No events on focus change (P2)

jim: (beyond moving to the next field in tab order) is troubling. I think it breaks keyboard user expectation that she needs to hit tab to move to next field

Level 2 Success Criteria for Guideline 3.2

3.2.3 Navigational mechanisms that are repeated on multiple Web units within a set of Web units or other primary resources occur in the same relative order each time they are repeated unless a change is initiated by the user. [How to meet 3.2.3]

3.2.4 Components that have the same functionality within a set of Web units are identified consistently. [How to meet 3.2.4]

  • 9.3 Move content focus (P1)

Level 3 Success Criteria for Guideline 3.2

3.2.5 Changes of context are initiated only by user request. [How to meet 3.2.5]

  • 9.3 Move content focus (P1)
Principle 4: Content should be robust enough to work with current and future user agents (including assistive technologies) UAAG 1.0
Guideline 4.1 Support compatibility with current and future user agents (including assistive technologies)
  • 2.1 Render content according to specification (P1)
  • 6.1 Programmatic access to HTML/XML infoset (P1)
  • 6.2 DOM access to HTML/XML content (P1)
  • 6.3 Programmatic access to non-HTML/XML content (P1)
  • 6.4 Programmatic access to information about rendered content (P1)
  • 8.2 Conform to specifications (P2)

Level 1 Success Criteria for Guideline 4.1

4.1.1 Web units or authored components can be parsed unambiguously and the relationships in the resulting data structure are also unambiguous. [How to meet 4.1.1]

4.1.2 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. [How to meet 4.1.2]

4.1.1

  • 2.1 Render content according to specification (P1)
  • 8.2 Conform to specifications (P2)

4.1.2

  • 6.1 Programmatic access to HTML/XML infoset (P1)
  • 6.2 DOM access to HTML/XML content (P1)
  • 6.3 Programmatic access to non-HTML/XML content (P1)
  • 6.4 Programmatic access to information about rendered content (P1)
Guideline 4.2 Ensure that content is accessible or provide an accessible alternative  

Level 1 Success Criteria for Guideline 4.2

4.2.1 At least one version of the content meets all level 1 success criteria, but alternate version(s) that do not meet all level 1 success criteria may be available from the same URI. [How to meet 4.2.1]

4.2.2 Content meets the following criteria even if the content uses a technology that is not in the chosen baseline: [How to meet 4.2.2]

  1. If content can be entered using the keyboard, then the content can be exited using the keyboard.
  2. Content conforms to success criterion 2.3.1 (general and red flash).
  

Level 2 Success Criteria for Guideline 4.2

4.2.3 At least one version of the content meets all level 2 success criteria, but alternate version(s) that do not meet all level 2 success criteria may be available from the same URI. [How to meet 4.2.3]

 

Level 3 Success Criteria for Guideline 4.2

4.2.4 Content implemented using technologies outside of the chosen baseline satisfies all Level 1 and 2 WCAG requirements supported by the technologies. [How to meet 4.2.4]

 

Author: Jim Allan
Last updated: April 18, 2006