- From: <peter.b.l.meijer@philips.com>
- Date: Wed, 1 Dec 1999 19:00:50 +0100
- To: <w3c-wai-ua@w3.org>
- Cc: <ij@w3.org>
[Again, I implicitly refer only to access for blind users in the text below, but we may generalize the issues later on to include other disabilities.] Thank you very much, Ian, your comments indeed do clarify some things to me, but at the same time begin to confuse me to the extent that I may start asking silly questions about what the main target audience is for these UA guidelines: whether it is those involved in developing accessibility layers (e.g. screen reader developers), or those involved in general applications that may need to adhere to some extra rules to match what screen reader technology can do, or both groups. To cite a few sections from the guidelines: > User Agent Accessibility Guidelines 1.0 > ... > "User agents must satisfy natively all the applicable > ^^^^^^^^ ^^^^^^^^^^ > checkpoints for a chosen conformance level." where applicable is further defined as > If a user agent offers a functionality, it must ensure > that all users have access to that functionality or an > equivalent alternative. and native support as > A user agent supports a feature natively if it does not > require another piece of software (e.g., plug-in or > external program) for support. and you add > To avoid the dependencies you describe below (e.g., works > with one screen reader but not with another), we decided > that conformance would not include tools used in combination. Consequently, according to these guidelines and your notes, web browsers like Microsoft Internet Explorer and Netscape are w.r.t. the current conformance requirements not accessible user agents for blind people, because these user agents are of no use to them without a combination with, for instance, a screen reader (an external program). The same similarly applies to my image sonification user agent. If so, that indeed avoids the complicating dependencies that I discussed, by excluding the vast majority of applications that are in practice accessible to blind people, but only in combination with a screen reader or equivalent third-party assistive technology. Yet the abstract of the guidelines begins with > An accessible user agent allows users with disabilities to > retrieve and view Web content or to enable access when used > in conjunction with other software or hardware, called > assistive technologies. where assistive technologies include screen readers. > These guidelines discuss the accessibility of the user > agent as well as how the user agent communicates with > assistive technologies such as screen readers, screen > magnifiers, braille displays, and voice input software. So now external programs like screen readers seem allowed, and thus MSIE, Netscape, and my sonification browser would appear accessible (give or take a few minor changes that may still be needed to really meet all of those new checkpoints). I'm lost here! I could force myself to consistently interpret things by assuming that the conformance definition suddenly adds the major burden of requiring full native support for screen reading functionality, but it seems rather strange that a tool that could quite well get a triple-A conformance rating for blind users *if* a combination with a third-party screen reader were allowed in the requirements, now drops to a zero-A conformance rating. There will then be many fully accessible user agents around that get a zero-A rating? Who will care for this rating then if its scope is this narrow? I'm sorry if I misinterpreted you, but when I get confused here, others may share that same fate. I would have hoped for a wide scope for the conformance requirements, although that would indeed imply that some sort of reference screen reader functionality must be defined to get around the complicating dependencies that I discussed in my previous posting. What I would have strongly hoped for is that a minimum set of functions is defined that the "reference screen reader" can be assumed to perform. All screen reader developers will then be motivated to provide at least this minimum functionality (and probably more to make them stand out from the crowd), such that they can brand their product as triple-A compliant with the guidelines, while on the other side many developers of (general) applications will be motivated to provide full access under this minimum set, e.g., by using only standard buttons, checkboxes and so on such that they can brand their product too as triple-A compliant with the guidelines. The blind user will then know that if he or she uses a triple-A screen reader together with any triple-A general application, that full accessibility is ensured. Moreover, the fact that only one screen reader installation is required (the one preferred by the blind user) helps to ensure a consistent "look-and-feel" across applications. For instance, the blind user will probably prefer having a single speech engine to access most applications. In addition, this is by far the most economical way of working, because few application developers will want to take the major effort/cost of including a screen reader to make their tool triple-A compliant, while screen reader developers lack the expertise to develop the best-in-class mathematics package, or browser, or whatever application you may think of. We need a well-defined interface in the middle to best combine the expertise of screen reader developers with the expertise of application developers. Until this definition has been worked out, it would seem best to drop (postpone) the conformance rating altogether? The UA guidelines will then indeed "just" be guidelines for the time being, but that will be a good and useful start already. In my personal opinion, a conformance rating is not ready for prime-time yet: it is currently either too narrow in scope to be useful or it shows too many interdependency pitfalls when it allows for tools used in combination. Best wishes, Peter Meijer The vOICe Internet Sonification Browser http://ourworld.compuserve.com/homepages/Peter_Meijer/eyebrows.htm
Received on Wednesday, 1 December 1999 13:01:51 UTC