- From: Gregg Vanderheiden <gv@trace.wisc.edu>
- Date: Tue, 21 Mar 2006 23:23:17 -0600
- To: "'Bailey, Bruce'" <Bruce.Bailey@ed.gov>, <w3c-wai-gl@w3.org>
- Message-ID: <033801c64d70$bb6ee240$ef64d946@NC6000BAK>
Hi Bruce, Feels funny since I just saw you downstairs. You make a good point. These were meant to describe what we were doing more or less - but at this point they look more definite than they are. What puts something into one level or another is a very complex mix of - Impact on disabilities (absolute barrier that can't be overcome by AT for example) - applicability across websites - Do-ability across websites - Impact on appearance of default page presentation - Effort - Support - Etc Perhaps we should just say * Level 1 success criteria: 1. Achieve a minimum level of accessibility 2. Can reasonably be applied to all Web resources. * Level 2 success criteria: 1. Achieve an enhanced level of accessibility 2. Can reasonably be applied to all Web resources. * Level 3 success criteria: 1. Achieve additional accessibility enhancements for people with disabilities. 2. Are not necessarily applicable to all Web resources. Gregg -- ------------------------------ Gregg C Vanderheiden Ph.D. Professor - Ind. Engr. & BioMed Engr. Director - Trace R & D Center University of Wisconsin-Madison The Player for my DSS sound file is at http://tinyurl.com/dho6b <http://tinyurl.com/cmfd9> _____ From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of Bailey, Bruce Sent: Tuesday, March 21, 2006 1:45 PM To: w3c-wai-gl@w3.org Subject: RE: normative issues to close > If you know of any others - please let me know I still don't believe the distinction between WCAG 1.0 priorities and WCAG 2.0 levels is clear enough. I say this, despite working hard to understand, and despite Gregg's having explained it two me twice on the phone in recent weeks. The conformance section [1,2] makes it explicit that priority and level "differs in important ways" and all levels of success criteria "are essential for some people." The intent is clear that "importance" as a paraphrase for level is not appropriate (although this worked with WCAG 1.0 priorities), but not enough has been given to replace the former concept. The difference between "minimum", "enhanced", and "additional" accessibility is not defined. I am going to work backwards from Level 3 to level 1. "Level 3 success criteria ... are not applicable to all Web resources." Okay, fine, very understandable. So far, so good. "Level 2 success criteria achieve achieve an enhanced level of accessibility through ... the design of the content and presentation." This is also very understandable, and we went through a great exercise with an earlier draft labeling SC as invisible or not. But this is the first potential problem I think: 1) Do we not have some non-invisible SC that are level 1? If so, what is the justification for that? Is this discussed in the Understanding WCAG? But, non-invisibility is not the only reason for making a SC level 2. There is also: "Level 2 success criteria achieve an enhanced level of accessibility through ... markup, scripting, or other technologies that interact with or enable access through user agents, including assistive technologies." But the *only* difference between this and level 1 definition is "an enhanced" versus "a minimum". What is the objective measure for when "markup, scripting, or other technologies" goes from level 1 to level 2? I cannot find it. This leads to the next two problems I find with the normative material (and not potential either, since maybe there are no invisible level 1 SC). 2) The considered deliberation of setting a particular SC as level 1 or 2 based is not clearly reflected in the Guidelines. If one wants to understand why a particular SC is level 2, one has to do a great deal of research through the wiki and the minutes. 3) Adding to the above, it is not clear when it is markup (etc.) or non-invisibility -- or both -- that causes a SC to be level 2. Again, maybe could be researched through wiki and the minutes, but why make readers work that hard? I have a proposal to address the above three concerns: <current> Level 2 success criteria: 1. Achieve an enhanced level of accessibility through one or both of the following: a. markup, scripting, or other technologies that interact with or enable access through user agents, including assistive technologies b. the design of the content and presentation 2. Can reasonably be applied to all Web resources. </current> <proposed> Level 2 success criteria: 1. Achieve an enhanced level of accessibility through one or both of the following: a. more complex markup, scripting, or other technologies that interact with or enable access through user agents, including assistive technologies; b. significant impact on the design of the content and presentation. 2. Can reasonably be applied to all Web resources. </proposed> The above makes it more clear that WCAG 2.0 conformance level has less to do with importance and more to do with level of effort or impact on site. This also provides the wiggle room for a non-invisible SC to be Level 1 and makes the reason why a particular SC is Level 2 less crucial. I also tweaked the ending punctuation. Also, the "Examples of conformance claims" need to be double checked. The one that I spotted first: Example 1 ... Safari 1.2 (Mac), and Opera 7.5 (OSX). Should probably be: Safari 2.0.3 (OS X), and Opera 7.54u2 (OS X). I am not sure how specific examples should be with regard to versions. Other numbers cited should also be double checked. [1] http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-20060317/conformance.html [2] http://trace.wisc.edu/wcag_wiki/index.php?title=New_Conformance_Section
Received on Wednesday, 22 March 2006 05:23:26 UTC