- From: Chris Ridpath <chris.ridpath@utoronto.ca>
- Date: Fri, 11 Feb 2005 10:06:44 -0500
- To: "WAI WCAG List" <w3c-wai-gl@w3.org>
During the development of the test suite we've run into some confusion relating to conformance levels and what is "required" to fulfill a success criteria. Here's a proposal that tries to clear up some of the confusion. The guidelines state that for conformance you must meet the success criteria. You are not required to exceed the success criteria and you can't come below the success criteria. You've got to "meet" it. I'll use guideline 1.1 SC 2 as an example. To meet this SC, for HTML content, images must have alt text. The quality of the alt text is also taken into account because the SC says it must "convey the same information" as the image. You can't put garbage in the alt text because that would be below what is needed to meet the SC. You're not required to enter excellent alt text because that would exceed the SC. You've just got to put in medium grade alt text. Sounds simple but there is a problem - the idea of conformance levels has been lost. There is no longer any "minimum" level and there is no longer any "increased accessibility" level. The 3 levels for conformance are now gone. We can't have minimum level alt text and we can't have "increased level" alt text. There's no "minimum" level for table markup and no "increased level" for table markup etc. The root of the problem is that the conformance level is set by the general SC. Currently, conformance level is not specific for each technology. PROPOSAL I propose that if a technology specific conformance process exists then it may set its own conformance levels. In effect, this would allow for 3 levels of alt text. Moving the conformance level down to the technology specific conformance process makes sense. Each technology will be able to determine exactly what is required for conformance much better than the general SC. This would fix the problem of tests and techniques getting mapped to inappropriate conformance levels. We've already got documents that flow from general down to specific so this is normal. We need to very clearly state exactly what is required to fulfill the guidelines at a specific level. Moving the conformance level down to the specific technology level will allow us to do that. If there is no technology specific conformance process then the general SC levels would prevail. With regard to the HTML test suite - this would allow us to state which tests were required to fulfill the guidelines at each level. There would be no "optional" or "advisory" tests. The tests would be sorted according to priority into the 3 levels as specified by the guidelines. I think we should use the 3 levels already in the guidelines rather than creating new categories such as "optional" or "advisory". Cheers, Chris
Received on Friday, 11 February 2005 15:07:36 UTC