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Accessible Art Web site - Null ALT text


From: Adam Alonzo
Date: Dec 19, 2001 10:52AM

> There are a number of places where there is an image associated with a link
> or title, where the alt text simply repeats the text of the link or title,
> for example the ACCESSIBILITY, CREDITS and CONTACT links at the bottom of
> http://tours.daytonartinstitute.org/accessart/ . I wonder if it might not
> be repetitive to a screen reader user? Taking the view that these images
> add something only for sighted readers who download images, would it be
> better to use null alt text for these? Or would that violate some
> recommendation?


Thanks for your feedback. Right or wrong, I would never use null ALT
text, preferring instead to identify every image in some way. In most
cases, the ALT text places the image within the context of the page
("Guided Tours" for example) rather than describing what the image
looks like, since all graphics are described elsewhere:


As you pointed out, this often has a repetitive effect for visitors who
use screen readers. I welcome their feedback, but only one such user
has inquired about it so far. When I explained the purpose of the ALT
text, he accepted it.

In answer to your question about violating recommendations, I used
the Web Accessibility Initiative's Web Content Accessibility
Guidelines as the accessibility standard for this site. Under its
first guideline about providing text equivalents, it states:

"Text equivalents must be provided for logos, photos, submit
buttons, applets, bullets in lists, ASCII art, and all of
the links within an image map as well as invisible images
used to lay out a page."


While it does suggest using an asterisk as ALT text for a graphical
bullet, I haven't found a reference to the practice of null text.

Other accessibility guidelines may make different recommendations.
For instance, the Access Board's guidelines (Section 508) state:

" . . . text descriptions are limited to those elements that
provide information required for comprehension of content
or those used to facilitate navigation. Web page authors
often utilize transparent graphics for spacing. Adding a
text description to these elements will produce unnecessary
clutter for users of screen readers. For such graphics, an
empty ALT attribute is useful."


I suppose it comes down to which standard you choose to follow,
and how you interpret the significance of the graphics.

Thanks again,

Adam Alonzo
Accessible Arts! Coordinator
Office of Disability Services
Wright State University
3640 Colonel Glenn Highway
Dayton, Ohio 45435-0001
(937) 775-5806