Conformance Section with best practise proposal

Firstly belted regrets for missing stuff for a while. I have been traveling.

I think we need to add to the conformance section that: in many cases it is the best practices that will make content accessible. Best practices are so called because they are hard to test, not because they are unimportant to accessibility. Hence full accessibility at any level require using best practices.

 I am also proposing that  level 1 complete (or parallel conformance statement) should be available so that people can claim that they believe that they used best practices. Although not strictly testable it will be clear when this claim is blatant rubbish. We can even add sample tests.


  ----- Original Message ----- 
  From: Gregg Vanderheiden 
  Sent: Sunday, October 31, 2004 4:47 AM
  Subject: 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 accessibility 

  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 made.

  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  
  For a list of our list discussions




Received on Friday, 5 November 2004 08:07:03 UTC