[thelist] AJAX and screen readers

David Kaufman david at gigawatt.com
Tue Sep 5 23:51:00 CDT 2006

Matt Warden <mwarden at gmail.com> wrote:
> I am doing research on ways to use AJAX in a ADA-compliant manner. The
> issue I cannot figure out how to solve has to do with page updates.

Conventional wisdom used to be: Browse your site using Lynx or another 
purely text-based browser.  You can easily see (and read) the way that 
your pages would be read to a visually impaired visitor by virtually all 
"screen reader" software out there.  Lynx, like the screen readers at 
the time, had no Javascript capability whatsoever so, to comply with 
Section 508 standards (as more and more publicly funded organizations in 
the U.S. must) their sites cannot rely on Javascript for primary 

See http://www.section508.gov/

The AJAX must gracefully degrade to old-school links, making the same 
content accessible via traditional static pages loaded the old fashioned 
way.  Think of it as SHOW: Synchronous HTML Over the Web :-)

Of course, these accessibility best-practices have been recommended for 

- providing fallback-links within <noscript> tags for non-js-capable 

- maintaining meaningful alt-tags on important images (such as 
form-submission buttons) and *empty* alt-tags on the meaningless images 
(to help screen readers bypass the clutter)

- providing invisible but screen-readable "skip to content" anchor links 
to allow the screen "readee" to skip hearing your site's top and 
left-nav menus recited over and over to them, on each page load, before 
they can read the *content* on any page...

But almost no sites do any of it.  Commercial web design tools barely 
allow, much less encourage such practices, and unless you've got a 
government-sized budget to develop and maintain sites that way, such 
"ideals" never seem to become high enough priorities for businesses to 
make actually make their sites truly accessible.

> My understanding is that the screen reader may not convey this
> [information updated via Javascript] to the user. My questions:
> (a) Is this true?

It certainly used to be.  And even if the latest round of 2006 screen 
readers don't completely ignore Javascript as they used to just 2-3 yeas 
ago, most disabled users tend to be on fixed incomes, so only a very 
small fraction of the "target population" will have the latest and 
greatest software and/or hardware to run it so I'd say: be conservative 
in what you assume about their O/S and software.

> The problem is that we do not have the equipment at the client site to
> test this out. Anyone with experience in this area... I'd love to hear
> your thoughts.

Google around and I'm sure you'll find whole communities of visually and 
otherwise-abled users happy to give your site a test drive and tell you 
what works and what doesn't.

And if you're serious about it, don't limit your planning to "visually 
impaired" visitors -- take a moment to think about the motion impaired, 
too.  Lots folks can control their computers only by voice and can make 
it can do anything you can do with a keyboard... but even the simplest 
mouse actions are impossible for them.  They don't have the javascript 
limitations though, so as long as you added an 
onkeypress="this.onClick()" wherever you had a 
onclick="doSomethingFancy()" then visitors without motor ability were 
still good to go...

Another thing to keep in mind is making sure that all the fonts used on 
your site can be scaled to very large point sizes.  This doesn't need to 
be pretty: just possible!  There are a lot more people with limited 
vision who just can't read small or (to us) normal-sized text including 
of course, most elderly folks, than there are users who need (and can 
afford) screen reader software.  Simply specifying base font sizes in 
em's (instead of points or pixels) and then relative sizes as 
percentages of increase or decrease can mean the difference between the 
site being a joyful relief or hopelessly frustrating for millions of web 
users out there.

> (d) Any other ideas?

IBM used to make demo software and development kits available that were 
excellent.  They are probably still leading the world in Accessible 
Software (as well as creative euphemisms for disabilities):




And most clients asking for accessibility have some public funding and 
some budget set aside for at least trying to implement some of it.

Hope this helps, and good luck to you, Matt!


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