Report of the HTML4/CSS2 Accessibility Review
Last revised October 24. 1997
This web page provides a guide to materials supporting the WAI review
of HTML4 and CSS2 recommendations nominated by the HC Working Group
and reviewed by the WAI Interest Group.
Pointers to detailed proposals is
included. The recommendations are summarized very tersely here,
and decorated with
a few links to influential source materials.
This page will be
maintained to try to keep it within 24 hours of current with respect
to current discussion during the period from October 15th to
Nov 10th.
How to use this document
Monitor this document at
http://www.w3c.org/WAI/group/HC/report.html (corrected 24 Oct).
Where this document refers to messages in the email archives,
please take advantage of the thread index to read related discussion
before and after the cited message.
If discussing these proposals in the HTML or CSS working groups, please
cross-post to w3c-wai-hc@w3.org
as well.
Review of the issues
The five thread-starters have symbolic names to help keep the discussions
straight. Please use these naming conventions in your replies to
facilitate dialog on the list-serve. The threads are:
- OPTION -- Making SELECT structures with lots of OPTIONs comprehensible
- TABLE -- Making TABLEs comprehensible
- DESC -- Text associated with images
- REF -- Associating HTML contents with external documents
- MEDIA -- Classifying user display and control
OPTION -- Making SELECT structures with lots of OPTIONs comprehensible.
Suggested WAI recommendations from HC Working Group:
-
A choice of two proposals at the level of functionality
comparable to the original proposal.
- OPTION
message sent to the IG mailing list on Oct 16th.
- Clarify what is actually critical for accessibility in this
area by discussion with the Interest Group.
- Original proposal from Megazone.
TABLE -- Making TABLEs comprehensible.
Suggested WAI recommendations from HC Working Group:
- TABLE
message sent to the IG mailing list on Oct 16th.
- The
baseline operational concept in the HC mail archives should
be regarded as having a rough consensus of support. The
implication is that the HTML should contain enough information
for browsers to perform these functions.
- Seek table reformatting functions from browser providers; refer
issue to WAI Browser Guidelines group for further work.
- add
SCOPE attribute.
- Clarify summary attribute to say that where there is a caption,
the summary should be written as if it will be said after the caption.
- address classes of tables (read by columns, read by rows, etc.) in
the markup guidelines using the existing CLASS attribute.
Refer to WAI Markup Guidelines group for further development, in cooperation
with the Browser Guidelines Working Group.
- Implement
LINK and
META enhancements in HTML4
to support experimentation by the WAI activities.
- Change the name of the AXES attribute to HEADERS. (added 24 Oct)
Background -- for reference: variety of practices integrating
image descriptions and image alternatives with images in hypertext
literature. See the GL group area.
Suggested WAI recommendations from HC Working Group:
- DESC
message sent to the IG mailing list on Oct 16th.
- Work with LONGDESC on IMG; normally inlined in the absense of
image display
- ADD TITLE and LONGDESC to FRAME and IFRAME
- OBJECT contents scanned for links with AREA on them which
function like a MAP entry when the image DATA of the object is
displayed.
Uses or requirements:
- Data publishers may wish to link TABLE to a resource (URL)
which clarifies data usage in the table.
- It is not safe to assume that all tables in one HTML document
are to be associated with the same such data dictionary
(or rough equivalent).
- Audio output [in general, not just for persons with disabilities]
will want access to pronunciation dictionaries.
- Acronyms and foreign languages are other applications for
such links.
- Stylesheets selectively applied to quotes etc.
Suggested WAI recommendations from HC Working Group:
- REF
message sent to the IG mailing list on Oct 16th.
- Seek review from RDF group
- Implement at least enough
LINK and
META enhancements
to ensure that dictionaries, including data dictionaries, can be
TARGETed to an arbitrary HTML container element.
Introduction to the
MEDIA types issue.
Suggested WAI recommendations from HC Working Group:
- MEDIA
message sent to the IG mailing list on Oct 17th.
- add another top-level media type named either CONSOLE or TTY for
character-grid and line-mode displays
- change wording around list of predefined MEDIA values to make
the list extensible. A browser _may_ ignore media indications that
do not match this list.
- Refer further work on how browser should handle this to browser
guidelines group.
Lesser issues
The following issues have been discussed in the HC group but appear to
be straighforward or otherwise not meriting a lot of discussion in
the brief time we have for Interest Group review.
Preserving the logical reading order
of text.
Example of problems as documented in the TRACE guidelines.
Suggested WAI recommendations from HC Working Group:
- Browser functions to crack tables referred to Browser
Guidelines WG for refinement.
- Explicit order-of-reading markup of text fragments referred
to Markup Guidelines working group for consideration.
LINK and META enhancements to be implemented in in
HTML4 to give the guidelines group enough capability to work with.
For background, search
The HC list archives for "order".
Browse both quarters; the thread runs over.
Image used as list bullet
The issue has to do with text alternatives to list bullets defined
by an image file.
Suggested WAI recommendations from HC Working Group:
- No change required to HTML.
- Continue work with CSS group in Markup Guidelines activity of WAI.
Controlling dynamic features
Gregg Vanderheiden copied over
a good summary by Kelly Ford.
For more background search the webwatch-l
digest archive for
"dynamism".
Suggested WAI recommendations from HC Working Group:
Refer to Browser Guidelines and Markup Guidelines for further
consideration.
The CSS2 spec being still under development, we haven't reached the
same level of reviewing in this area.
The HC message Regarding
CSS2 summarizes our position.
Daniel Dardailler,
Project Manager of
the W3C Web Accessibility Initiative Working Group
Al Gilman,
Chair of
the WAI HTML4/CSS2 (HC) Review Working Group