Impact on ATAG Wombat of Changes to WCAG's Priority Scheme

As a result of our decision on the last call to update our references to
WCAG 1.0 to WCAG 2.0 we need to take into account that WCAG 2.0 has a
different priority system:

http://www.w3.org/WAI/GL/WCAG20/#priorities-techs

As a result we will need to make changes to the way that Relative
Priority checkpoints in ATAG work (see [1] below) and modify checkpoint
7.2 (see [2] below).

[1]

Here is my proposal for a reformulation of "Relative Priority":

[Relative Priority]
Assigned when the checkpoint requires implementation of some
functionality (i.e. generating, checking, repairing, etc.) for which
some or all of the checkpoints in the Web Content Accessibility
Guidelines (WCAG) 2.0 [WCAG20] are relevant. This priority level is
relative to reflect the fact that the requirements of the WCAG 2.0
checkpoints are not all equally important for the accessibility of Web
Content. WCAG 2.0 handles these differences in requirement importance by
establishing three different levels of conformance for each checkpoint:
minimum (for the most important requirements), level 2 and level 3 (for
the least important requirements). As a result ATAG Wombat Relative
Priority checkpoints inherit their priorities as follows: 

Relative Priority - Level "A": The checkpoint satisfies relevant WCAG
2.0 checkpoint requirements to at least the minimum level.

Relative Priority - Level "Double-A": The checkpoint satisfies relevant
WCAG 2.0 checkpoint requirements to at least level 2.

Relative Priority - Level "Triple-A": The checkpoint satisfies relevant
WCAG 2.0 checkpoint requirements to at least level 3.

For example:

ATAG checkpoint 5.1 is a relative priority that requires tools to check
for accessible content as defined by the requirements of WCAG 2.0. This
means that if the tool checked for the minimum and level 2 requirements
of several WCAG checkpoints, but only the minimum requirements for the
rest, the tool would receive Relative Priority - Priority 1 for ATAG
checkpoint 5.1.

Note: The priority level for each checkpoint has been chosen based on
the assumption that the author is a competent, but not necessarily
expert, user of the authoring tool, and that the author has little or no
knowledge of accessibility. For example, the author is not expected to
have read all of the documentation, but is expected to know how to turn
to the documentation for assistance.



[2]

Currently, checkpoint 7.2 says:

7.2 Ensure that accessible authoring practices supporting Web Content
Accessibility Guidelines 1.0 [WCAG10] Priority 1 checkpoints are among
the most obvious and easily initiated by the author.

I propose that 7.2 should be changed to read as:

7.2 Ensure that accessible authoring practices supporting the minimum
level requirements for all WCAG 2.0 [WCAG20] checkpoints are among the
most obvious and easily initiated by the author. 



Thoughts?


-- 
Jan Richards, User Interface Design Specialist
Adaptive Technology Resource Centre (ATRC), University of Toronto

  Email: jan.richards@utoronto.ca
  Web:   http://ultrajuan.ic.utoronto.ca/~jan/jan.html
  Phone: 416-946-7060
  Fax:   416-971-2896

Received on Thursday, 29 August 2002 09:29:56 UTC