General Exception for Essential Purpose

This is a proposal for a general guideline which will I think, help resolve 
the image text issue, and other issues as well. Its a modification of WCAG 
1.0 checkpoint 11.4 on alternative pages.    It also needs to be added to 
WCAG 2.0--I don't see an equivalent to 11.4 in 2.0.

Here's straw wording of what I'll call the "essential purpose" guideline.

<guideline>
If a web page's essential purpose prevents you from satisfying a 
checkpoint, you can consider that checkpoint passed if the user can 
conveniently access an alternative page on which the checkpoint is satisfied.
</guideline>

Here's how it applies to images of text.  Note that images of text is just 
one application.

Consider a "chilly" font, where all the characters have icicles dripping 
from them.  Terrible for someone with low vision.  The "essential purpose" 
guideline lets you use that font in some situations but not others.  Here's 
some examples.

1. Consider a site teaching kids to read, where the word "cold" is written 
in chilly font.  This plausibly supports the pages essential purpose, 
teaching reading, since its a memory aid for the kids, and may also help 
keep their attention.  So chilly font is allowed here, provided the user 
can access an alternate page with real text.

2.  But now consider a schedule of public meetings of a township zoning 
board, where all the winter dates are written in chilly font.  This would 
not be allowed, even if there is an alternate page with ordinary text, 
because chilly font doesn't support the essential purpose of the page, to 
inform citizens when they can attend public meetings.

3. Consider an artistic page, with images and poems about winter.  I'd 
argue that chilly font is acceptable, since the essential purpose of the 
page is artistic expression.  It would be acceptable even if it goes beyond 
occasional use as "accent elements".

4. Now imagine a hypothetical web site for a company "frosty cola".  I'd be 
inclined to allow the chilly font on a splash screen, even if it's used all 
over the page, not just on accent elements.  I'd accept the argument that 
the purpose of the page is to increase sales of frosty cola, and that 
chilly font creates a association in the customer's mind that will further 
that goal.  However, job listings at frosty cola should be in standard 
text, because the essential purpose of those pages is to give objective 
information about job openings.


People familiar with the US ADA laws will recognize a similarity with the 
ADA's definition of "essential job function" by the way.

Len



--
Leonard R. Kasday, Ph.D.
Institute on Disabilities/UAP and Dept. of Electrical Engineering at Temple 
University
(215) 204-2247 (voice)                 (800) 750-7428 (TTY)
http://astro.temple.edu/~kasday         mailto:kasday@acm.org

Chair, W3C Web Accessibility Initiative Evaluation and Repair Tools Group
http://www.w3.org/WAI/ER/IG/

The WAVE web page accessibility evaluation assistant: 
http://www.temple.edu/inst_disabilities/piat/wave/

Received on Friday, 27 October 2000 06:15:18 UTC