Re: WCAG Priority Levels for accessibility-oriented TABLE eements and attributes


These 2 checkpoints are P3 because providing a summary or header 
abbreviations make it "easier" to get the info from a table.  If an author 
does not provide a summary or header abbreviations, it is not making it 
"impossible" or "difficult" to access the information in a table. UNLESS a 
summary is so well written that a user would not need to access the 
table.   Therefore, I could see upgrading "summary" to P2 for complex 
tables, p3 for others.  Headers I still see as "helpful" i.e. they decrease 
reading time and annoyance (based on the current WCAG use of the "abbr" 
attribute and not ABBR element.  ABBR issues are handled in checkpoint 4.2, 
also a P3).

Yes, authors should be encouraged to provide as much semantic information 
as possible.  The WCAG prioritizes that info based on how well it can help 
the user access the information, in this case we are refering to the TABLE 
element.  Summaries and table header abbreviations do not help access 
nearly as much as appropriate structure, identifying headers, etc.

unless you can prove me otherwise...


>At 07:22 PM 12/15/99 -0500, Gregory J. Rosmaita wrote:
> >aloha, ian!
> >
> >during the afternoon session of the User Agent Working Group meeting in 
> austin
> >on 10 december 1999, you assured me that all of the accessibility attributes
> >and elements contained in HTML4 that are defined for tables are accorded 
> P1 in
> >WCAG...  however, WCAG Checkpoints 5.5 and 5.6 (which deal with the summary
> >attribute for TABLE and the abbreviation attribute for TD and TH are only
> >accorded P3...  if non-visual access to tabular information (i.e. the 
> ability
> >to search within a table, a nested table, a column or row; the ability 
> to read
> >across rows and down columns; the ability to obtain extended contextual
> >information from a cell in a nested table, etc.) is left to AT interaction
> >the DOM and relies upon proper usage of TABLE elements and attributes, then
> >_all_ of the semantic slash contextual markup defined for tables in HTML4
> >to be accorded a P1 in WCAG, so that authors provide as much semantic and
> >contextual information as possible when they create a table...  this is the
> >only way that a user's adaptive technology will be able to use the DOM to
> >extract semantic information from the TABLE, so as to provide information
> >will orient the user, thereby making it possible for that user to use 
> whatever
> >navigational mechanisms his or her AT has provided for traversing tables...
> >
> >moreover, both the summary and the abbr attributes are clearly identified in
> >the HTML4 TR as accessibility features
> >
> >the HTML4 definition of the "summary" attribute
> >
> >states
> >
> >quote
> >summary = text [CS]
> >   This attribute provides a summary of the table's purpose
> >   and structure for user agents rendering to non-visual
> >   media such as speech and Braille.
> >unquote
> >
> >while the HTML4 definition of the "abbr" attribute
> >
> >states:
> >
> >quote
> >abbr = text [CS]
> >   This attribute should be used to provide an abbreviated form
> >   of the cell's content, and may be rendered by user agents
> >   when appropriate in place of the cell's content. Abbreviated
> >   names should be short since user agents may render them
> >   repeatedly. For instance, speech synthesizers may render
> >   the abbreviated headers relating to a particular cell before
> >   rendering that cell's content.
> >unquote
> >
> >thus, i would ask that ALL of the structural and contextual slash semantic
> >markup defined for TABLE in HTML4 be accorded a P1 in WCAG, for, as i was
> >minuted as stating at the austin face2face:
> >
> >quote
> >GR: I'm not opposed to using the DOM to walk the tree [in order to perform
> >navigation within tables]. The bottom line is authoring practices: misuse of
> >markup. Also, lack of implementation of axis/scope/caption/summary. If 
> we push
> >everything off to the DOM, it's meaningless unless all the pieces are 
> clearly
> >marked up and defined. I'm not asking for [the user agent to repair] poorly
> >marked up tables; however, for proper tables, the information needs to 
> be made
> >available. If we say "Get everything from the DOM" we need to ensure 
> that what
> >is needed is in the DOM in the first place.
> >unquote
> >
> >gregory.
> >--------------------------------------------------------
> >He that lives on Hope, dies farting
> >     -- Benjamin Franklin, Poor Richard's Almanack, 1763
> >--------------------------------------------------------
> >Gregory J. Rosmaita <>
> >   WebMaster and Minister of Propaganda, VICUG NYC
> >        <>
> >--------------------------------------------------------
>Jon Gunderson, Ph.D., ATP
>Coordinator of Assistive Communication and Information Technology
>Chair, W3C WAI User Agent Working Group
>Division of Rehabilitation - Education Services
>College of Applied Life Studies
>University of Illinois at Urbana/Champaign
>1207 S. Oak Street, Champaign, IL  61820
>Voice: (217) 244-5870
>Fax: (217) 333-0248

wendy a chisholm
world wide web consortium
web accessibility initiative
madison, wi usa
tel: +1 608 663 6346

Received on Thursday, 16 December 1999 11:48:29 UTC