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RE: Use of Audio Interferes with Screenreaders?

for

From: John Foliot - WATS.ca
Date: Feb 5, 2004 4:15PM

Tom,

Hmmm... you've hit on a good one. Of course, in the "real world"
simultaneous audio tracks will be difficult to screen reader users.

To the first question:

Could a user experienced with JAWS adequately deal with this
situation?

This of course is not a fair question, as *how* much experience is required,
and what is your criteria for "adequate"? If two people were standing at
your desk, speaking to you simultaneously about two completely different
subjects, would you be able to fully comprehend and respond to both audio
streams? Perhaps, depends on the topic, right? But your experience in
"listening" is not the only skill brought into play, as you would also need
to (quickly) determine *the more important* stream, if you could in fact
only concentrate on one. But if you do not know which of the two is more
important, how can you decide? So this becomes then not only an issue for
the visually impaired user of screen reading AT, but also for users who may
have cognitive difficulties.

To the second question:

Would this situation... be a violation of any of the WAI conformance
levels?

This specific scenario is not directly addressed in either the current WCAG
1 or the draft WCAG 2, although perhaps it should be. The problem with WCAG
1 (and there are many of them) is that "auto-start" of multi-media content
is not addressed, and in WCAG 2 the authors are going for a more general
overview or "spirit of intent" document as opposed to specific do's and
don'ts. Yet neither addresses multi-media content in this way. So if you
are going for strictly "technical" conformance, then no, having two audio
streams commence simultaneously is not against the WCAG 1 Guidelines.

However, in the spirit of the guidelines (which, IMHO is the real point
here) this scenario is an accessibility "issue" which should be avoided. If
you need "documentation" to back up this position, it would only be through
inference:

WCAG 1 - Guideline 7. Ensure user control of time-sensitive content
changes.
"Ensure that moving, blinking, scrolling, or auto-updating objects or
pages may be paused or stopped."
The Guideline here discusses the fact that "...Some people with cognitive or
visual disabilities are unable to read moving text quickly enough or at
all." Close... Then there is checkpoint #7.5 "Until user agents provide
the ability to stop auto-redirect, do not use markup to redirect pages
automatically." While it speaks to "auto-redirect", one could expand this
to include "auto-start-anything", as what they authors here (I believe) were
looking at is giving control to the user.

WCAG 1 - Guideline 8. Ensure direct accessibility of embedded user
interfaces.
"Ensure that the user interface follows principles of accessible design:
device-independent access to functionality, keyboard operability,
self-voicing, etc."

Here, the guideline vaguely recommends that the ability to "work" an
embedded interface (or function) be accessible. It could be argued that
having two computer voices speaking to you at the same time removes the
ability to properly "control" the functionality. Checkpoint #8.1 states
"Make programmatic elements such as scripts and applets directly accessible
or compatible with Assistive technologies" Using my arguments so far, the
"applet" (embedded object - your Flash file) is not "directly"
accessible..., yes, but directly?...

WCAG 1 - Guideline 9. Design for device-independence.
"Use features that enable activation of page elements via a variety of
input devices."

Here, the guideline states: "Device-independent access means that the user
may interact with the user agent or document with a preferred input (or
output) device -- mouse, keyboard, voice, head wand, or other." I would
interpret this again as giving the user the choice as to how they initially
access the web content, including the Flash file. Making it auto-start
takes away the users preference (again, IMHO).

Looking forward, WCAG 2 comes pretty close to addressing this topic without
specifically mentioning it.
It proposes:
Guideline 2: OPERABLE. Ensure that Interface Elements in the Content are
Operable by Any User
2.2 [CORE] Users can control any time limits on their reading,
interaction, or responses unless control is not possible due to nature of
real time events or competition.
Benefits of Checkpoint 2.2 (Informative): "People with reading
disabilities, cognitive disabilities, and learning disabilities often need
more time than most people to read and comprehend written text. People with
physical disabilities might not be able to move quickly or accurately enough
to interact with moving objects. Content that is updated often might not be
processed and read in time or in the proper order by an Assistive technology
or voice browser."

I would argue that having an auto-start anything violates the basic premise
that "Users can control any time limits", but again, this is interpretive,
not specifically mandated. And while the authors speak of "moving objects",
the same issues are in fact present here with "moving audio" (i.e. audio
that starts without direct input from the user), but in a different way...

Anyway, I'm sure that this is a much longer response than you expected, but
you asked... <grin>

For me, bottom line, don't do it.

JF
--
John Foliot <EMAIL REMOVED>
Web Accessibility Specialist / Co-founder of WATS.ca
Web Accessibility Testing and Services
http://www.wats.ca 1.866.932.4878 (North America)