problem spotted.

 

In 1.4.2 we have a failure that is not derived from the SUCCESS CRITERION.
The three seconds is not in the SUCCESS CRITERION to we can't cite it as a
failure unless we add it to the SUCCESS CRITERION.   OK to have as
sufficient --- but not as failure.

 

Agree?

 

Gregg

 

 

 

 

 

 


How to Meet Success Criterion 1.4.2


1.4.2 A mechanism is available to turn off background audio that plays
automatically, without requiring the user to turn off all audio. (Level 2) 


Intent of this success criterion 


Individuals who use screen reading software can find it hard to understand
the speech output if there is other audio playing at the same time. This
difficulty is exacerbated when the screen reader's speech output is software
based (as most are today) and is controlled via the same volume control as
the sound. 


Techniques for Addressing Success Criterion 1.4.2


Each numbered item in this section represents a technique or combinations of
techniques that the WCAG Working Group deems to be sufficient to meet
success criterion 1.4.2 as long as the technologies used are in the baseline
you are using. All techniques listed would be helpful to some users.
However, they only satisfy the success criterion if all of the technologies
used are in your baseline. (Use of technologies not in the baseline is
allowed, but an alternate conformant version would be required per success
<http://www.w3.org/TR/2006/WD-WCAG20-20060427/guidelines.html#accessible-alt
ernatives-level1>  criterion 4.2.1.)

1.      Playing
<http://www.w3.org/TR/2006/WD-WCAG20-TECHS-20060427/Overview.html#G60>  a
sound that turns off automatically within three seconds 

2.      Playing sounds only on user request (future link) 

3.      Providing a control near the top of the Web unit that turns off
sounds that play automatically (future link) 


Common Failures Identified by the Working Group 


The following are common mistakes that are considered failures of success
criterion 1.4.2 by the WCAG Working Group.

*         Failure
<http://www.w3.org/TR/2006/WD-WCAG20-TECHS-20060427/Overview.html#F23>  of
SC 1.4.2 due to playing a sound longer than 3 seconds where there is no
mechanism to turn it off 

 

 


Gregg

------------------------

Gregg C Vanderheiden Ph.D. 
Professor - Depts of Ind. Engr. & BioMed Engr.
Director - Trace R & D Center 
University of Wisconsin-Madison 
< <http://trace.wisc.edu/> http://trace.wisc.edu/> FAX 608/262-8848  

The Player for my DSS sound file is at http://tinyurl.com/dho6b 

 <http://trace.wisc.edu:8080/mailman/listinfo/>