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Overview of the issues with different conformance schemes

The purpose of this page is to capture recent discussion about whether there should be 2 or 3 levels of conformance in WCAG 2.0.

Summary of Issue

WCAG 1.0 had 3 conformance levels and WCAG 2.0 also started out with 3. In WCAG 2.0 however the definition of what the 3 levels meant has changed. (See "WCAG 1.0 and 2.0 levels" below) The content of the guidelines has also changed with additional "things to do if you really want to make an accessible site" added to Level 3. Also Level 3 has items that could not be applied to all sites with all technologies. This change led some to suggest that level 3 be removed.

Others suggested that the guidelines just be simplified by taking the items in the three levels and redistributing them into 2 levels etc.

At a recent face-to-face meeting seven variations were proposed. All essentially proposing either 2 or 3 levels and distributing the current guidelines in different ways or labeling the groups differently.

Thus, the question is actually a combination of three questions:

Note: Independent of the 2 levels or 3 levels discussion, the group is continually evaluating all of the success criteria at all of the levels The question here is not about individual Success Criteria, but the restructuring of the guidelines and the treatment of the L3 success criteria as a whole. We expect to move and/or remove additional Success Criteria at more than one level before we are finished.

WCAG 1.0 and Current WCAG 2.0 Level Definitions

WCAG 1.0 Levels of conformance

Each checkpoint has a priority level assigned by the Working Group based on the checkpoint's impact on accessibility.

[Priority 1]
A Web content developer must satisfy this checkpoint. Otherwise, one or more groups will find it impossible to access information in the document. Satisfying this checkpoint is a basic requirement for some groups to be able to use Web documents.
[Priority 2]
A Web content developer should satisfy this checkpoint. Otherwise, one or more groups will find it difficult to access information in the document. Satisfying this checkpoint will remove significant barriers to accessing Web documents.
[Priority 3]
A Web content developer may address this checkpoint. Otherwise, one or more groups will find it somewhat difficult to access information in the document. Satisfying this checkpoint will improve access to Web documents.

Some checkpoints specify a priority level that may change under certain (indicated) conditions.

WCAG 2.0 Levels of conformance (current draft)

The success criteria for each guideline are organized into three (3) levels of conformance.

Note: Comments will be included in guidance doc that level 3 conformance should not be required by public policy since it is intended to list criteria for those who want to expend extra effort to make their sites more accessible where possible.

Summary of Issues

RE Having only one level of conformance with all else in second advisory level

Current Result and Questions

These results are basically consistent with the results each time this is revisited. In our latest round we were unable to reach consensus for any of the 3 or 2 level approaches proposed. (Consensus is defined as everyone says they can live with it, even if they might prefer something else.)

The greatest support currently was for the 3 level approach so this draft continues to have three levels. Because we do not have unanimous consensus on this however, this question is still open and we are seeking input from the field in the form of comments or any solutions that would address all of the concerns above.

The open questions are:

  1. should there be two levels or three levels?
  2. if two levels – how should items be redistributed between the two remaining levels? (and perhaps the guide doc)
  3. should all of the items in level 3 be removed from the guidelines?
  4. Is there a proposal that addresses all of the show-stoppers (issues listed above) to unanimous consensus - since unanimous consent is the groups goal wherever possible?

$Date: 2005/07/01 22:52:33 $ Prepared by Gregg Vanderheiden for the WCAG WG as a companion to the 30 June 2005 WCAG 2.0 Working Draft.