Conformance Section wtih Edits incorporated


Editorial Note: There are several open issues with the proposed conformance
scheme. This section outlines the conformance scheme used throughout this
document. Feedback, comments, and proposals are encouraged.

Success criteria for each guideline are categorized into three levels:

*         Level 1 success criteria: 

1.      Achieve a minimum level of accessibility through markup, scripting,
or other technologies that interact with or enable access through user
agents, including assistive technologies.

2.      Can be reasonably applied to all Web resources.

*         Level 2 success criteria: 

1.      Increase accessibility through one or both of the following:

a.       further facilitating the ability of user agents to provide
accessible content 

b.      recommends content and/or presentation that provides direct
accessibility without requiring users or their user agents to do anything
different from users without disabilities

2.      Can be reasonably applied to all Web resources.

*         Level 3 success criteria: 

1.      Go beyond Level 1 and 2 to increase direct and user agent enhanced

The Working Group believes that all success criteria should be testable.
Tests can be done by computer programs or by people who understand these
guidelines. Tests done by people who understand the guidelines should get
the same results testing the same content for the same success criteria. 

Editorial Note: To facilitate discussion related to the levels assigned to
each criteria, a square bracket notation is included at the end of each
criteria. "[I]" (invisible) indicates that a criterion does not specify how
information is presented and "[V]" (visible) indicates that addressing the
criterion may require an author to present content in particular ways.


Some guidelines do not contain level 1 success criteria.

Conformance Requirements

1.      Any conformance with WCAG 2.0 requires that all level 1 success
criteria for all guidelines be met.

2.      WCAG 2.0 conformance at level A means that all level 1 success
criteria for all guidelines are met. 

3.      WCAG 2.0 conformance at level AA means that all level 1 and all
level 2 success criteria for all guidelines are met.

4.      WCAG 2.0 conformance at level AAA means that all level 1, level 2
and level 3 success criteria for all guidelines are met.

The Working Group believes that provisions at all 3 levels are important or
essential for some people.  Thus the old descriptions of "impossible to
access" for Level A, "difficult to access" for Level AA, and "somewhat
difficult" for Level AAA are no longer used.  Instead we define the three
levels as above.

Conformance Claims

All conformance claims must include at least the following information: 

1.      The version of the guidelines to which the conformance claim is

2.      The URI of the delivery unit for which the claim is being made.

Editorial Note: There is some question as to whether URI is specific enough
a reference to the material for which the claim is being made.

3.      The level of conformance being claimed. 

Level of conformance being claimed. 

The conformance level for a delivered unit that contains other authored
units is equal to the lowest conformance level claimed for the delivered
unit content and any of the authored units it contains - including claims of
aggregated units.

Editor's Note #1: A question has been raised as to whether the information
required in items 1-3 above should all be transmitted in the HTTP header or
in some other way.

Editor's Note #2: We are currently looking at how to handle unknown or
community-contributed, authored units that are created using an aggregator
supplied tool. If the aggregator-supplied tool conforms to ATAG, can ATAG
conformance be used to imply that the aggregated content conforms to WCAG?

Scoping of Conformance Claims

Conformance claims can be scoped to pertain to only some parts of a website.
All conformance claims however must be directed to a URI or a range of URIs.
Scoping to exclude a particular type of content (e.g. images or scripts)
from a site is not allowed since it would allow exclusion of individual
success criteria.   Scoping by URI to exclude sections of a site is allowed
by making claims for just some parts of a site.  

Sites that conform to WCAG 1.0

Sites that currently conform to WCAG 1.0 that want to transition to WCAG 2.0
over time may want to capitalize on past accessibility efforts. A qualified
conformance statement could allow them this flexibility. For example, a
conformance claim might include the following statement, "Materials created
or modified before 24 April 2003 conform to WCAG 1.0. Materials created or
modified on or after 24 April 2003 conform to WCAG 2.0.  If a delivered unit
is modified in a significant way then the full delivered unit should be
brought up to WCAG 2.0"

Editorial Note: In some instances, the WCAG 2.0 Working Draft may be easier
to conform to than the WCAG 1.0 Recommendation while other criteria might be
harder to meet in WCAG 2.0 than in WCAG 1.0. The WCAG WG will consider the
differences between WCAG 1.0 and WCAG 2.0 conformance and offer advice to
developers who currently conform to WCAG 1.0. This advice might take the
form of a WCAG 1.0 conformance profile to WCAG 2.0 and information about
migrating from WCAG 1.0 to WCAG 2.0. This advice is not yet available.







Gregg C Vanderheiden Ph.D. 
Professor - Depts of Ind. Engr. & BioMed Engr.
Director - Trace R & D Center 
University of Wisconsin-Madison 
< <>> FAX 608/262-8848  
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Received on Sunday, 31 October 2004 02:48:06 UTC