- From: Jukka Korpela <jukka.korpela@tieke.fi>
- Date: Wed, 9 Oct 2002 15:29:45 +0300
- To: "'w3c-wai-gl@w3.org'" <w3c-wai-gl@w3.org>
I'll try to comment on Wendy's remarks on my message. Sorry for the delay in doing so. Wendy wrote: > Could you please list which WCAG 1.0 principles are "homeless?" I suppose I was mainly thinking about guidelines 10 and 11 ("Use interim solutions" and "Use W3C technologies and guidelines"). They are technically oriented and don't quite fit into the approach of the WCAG 2.0 draft. To put it in another way, guideline 5 in the draft now contains a mixture of technology-oriented principles that don't quite play in the same field as the other guidelines. Moreover, WCAG 1.0 guideline 5 (Clarify natural language usage) has been embedded into checkpoint 1.5 (Provide information needed for unambiguous decoding of the characters and words in the content) in the draft. This doesn't look very natural to me. The need for indicating the language used goes far beyond decoding issues (and the word "decoding" is even partly misleading here since it suggests connection with character encoding issues). > Could you give your reasons for wanting to move 4.2 under 1.1? I'd say that 1.1 tells us to provide textual alternatives to non-text content, and 4.2 is a dual principle of providing non-text alternatives to textual content. There's a difference of course: the first one is obligatory, the second one applies "where appropriate". This reflects how we regard text somehow as the solid basis of accessibility, as primarily accessible. We probably need to think about this, deeper than we've used to. Even if you don't make the two principles adjacent in the order, it was a thought-giving experiment to consider them that way. (On the practical side, I'm sure there are situations where textual content _needs_ non-text alternatives or augments, in a sense comparable to how images _need_ textual alteratives. For example, a merely verbal description of a bird species might be crystal clear to an experienced ornithologist, but most of use would really need some picture(s) and/or sound samples to understand what the bird is like. But I don't know whether it is possible to formulate general requirements on augmenting text with non-text content to make it accessible to all.) This relates to the general question about the relationship between guideline 1 (Perceivable) and guideline 4 (Understandable). Could non-text alternatives be part of the former, rather than the latter? Admittedly, text content is basically "perceivable" in the sense that it can be presented _somehow_ to a human being who is able to communicate at all. I think I see the reasoning behind the division into Perceivable (to senses) and Understandable (to the mind), but it wasn't very obvious. And it might have been easier if Understandable were presented right after Perceivable. > The technology-specifics for WCAG 1.0 are not normative, nor will the > technology-specifics for WCAG 2.0 be normative. Maybe they should be partly normative. Naturally they would be conditional: _if_ the technology used is such-and-such, then the guideline this-or-that shall be implemented so-and-so. This would often make the guidelines clearer (more accessible!), since often it's the mapping to a specific technology that makes people understand the intended meaning of a guideline. > I'm concerned about your statement that the European parliament considers the > techniques normative. I didn't mean the techniques document. My reference to WCAG 1.0 was somewhat vague; I meant the guidelines document itself. The wording in the resolution of the European parlament is: "K. whereas the world wide web consortium set up the web accessibility initiative (WAI) and the latter has developed the web content accessibility guidelines version 1.0 called "the guidelines" which are nowadays considered to be the global standard for the designing of accessible websites; - - - - [the parliament] 31. Stresses the fact that, for websites to be accessible, it is essential that they are double-A compliant, that priority 2 of the WAI guidelines must be fully implemented;" http://europa.eu.int/information_society/topics/citizens/accessibility/web/w ai_2002/ep_res_web_wai_2002/index_en.htm I'm afraid I've presented my point poorly. I'll try again: Currently, the WCAG 1.0 guidelines document contains rather specific recommendations, more specific than the content of the WCAG 2.0 draft. The WCAG 1.0 guidelines are widely regarded as "standards" or "normative" in some sense. If WCAG 1.0 guidelines and associated documents will be replaced by WCAG 2.0 that is at the current level of specificity, with some things currently in the WCAG 1.0 guidelines moved to techniques documents, then e.g. the European Union will probably update their documents to refer to WCAG 2.0 as normative. This will imply that the status of some important principles will drop. > People who try to implement WCAG 1.0 are often unable to > determine if they have met the requirements. Yes, especially since many of them are not objectively verifiable, still less checkable by computer programs. > Do you have a specific > suggestion for how we can provide clear guidance to authors? I don't know whether this helps anything in that respect, but I regard this as important for other reasons, including guidance to people who write accessibility checking and repair software: Technical rules (which are partly implementable as automated checks) can usually only identify items to be checked, not actual compliance with accessibility guidelines. Example: We can specify rather exactly how one can identify non-text elements on a page, and in part we can determine mechanically whether there is something presented in a position where a textual alternative is to appear. But this will not answer the question whether it specifies an adequate textual alternative to the non-text content. That's something that a human being needs to decide. The general thing we can say about this is probably just that the alternative should work in different situations, such as text-only display, speech presentation, and Braille presentation (and these might have somewhat conflicting requirements). Similarly, a guideline on writing as simply as possible/feasible could be made more operational by listing some ways to test the understandability, like asking people with comprehension problems to read it and explain the content. The guideline on providing methods to minimize error and provide graceful recovery could be made more concrete by saying that pages, especially interactive pages, should be tested by people are likely to make mistakes (or by someone who intentionally makes mistakes). But, unavoidably, this would normally just list _examples_ of testing methods, and mostly the testing would not give any decisive results. (Organizations might, of course, make some specific testing methods required, especially if they can decide that some particular tests are essential due to intended audience and content.) -- Jukka Korpela, senior adviser TIEKE Finnish Information Society Development Centre http://www.tieke.fi/
Received on Wednesday, 9 October 2002 08:30:15 UTC