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PLAIN: Proposed rewording for Guideline 2.3 with success criteria, best practices, benefits, and examples

From: John M Slatin <john_slatin@austin.utexas.edu>
Date: Wed, 5 Nov 2003 16:37:50 -0600
Message-ID: <C46A1118E0262B47BD5C202DA2490D1A1E2FFC@MAIL02.austin.utexas.edu>
To: <w3c-wai-gl@w3.org>
Plain language version of Guideline 2.3 with success criteria, benefits,
and examples

 

This document contains a series of proposals for a "plain language_
rewording of WCAG 2.0 Guideline 2.3 with Success Criteria, Examples, and
Benefits

 

This is submitted in partial fulfillment of an action item taken by John
Slatin, Katie Haritos-Shay, and Doyle Burnett during a call in late
September or early October, to generate a plain-language version of WCAG
2.  

 

This message is partial in two ways: (1) It addresses only Guideline
(now Principle) 2, Checkpoint (now Guideline) 2.3, and the relevant
success criteria, examples, and benefits.  Other guidelines, etc., will
follow.  (2) It is not really "plain language," in the sense that this
text has not yet been compared to the 1500-word "special lexicon" used
by Voice of America (or other similar lexicons).  Thus it's actually
best understood as an attempt to simplify and clarify.  We're still
working on the formal plain language issues, but wanted to put this out
to start generating discussion.

 

Items labeled "Current wording" are taken from the September document
Reorg 4, available at http://www.w3.org/WAI/GL/2003/09/reorg4.html
<http://www.w3.org/WAI/GL/2003/09/reorg4.html> .  This document was
current at the time Katie and Doyle and I took on the action item to
attempt a plain language version.  Of course the proposed rewordings
will need to be correlated with later updates.


Current wording for Checkpoint 2.3


2.3 [CORE] User can avoid experiencing screen flicker.

 

Editorial Note (06/10/03): This Checkpoint is currently included in the
Core set of Checkpoints because the WCAG WG expects that it will be
possible to test content for flicker and the result will be a flicker
rate in Hz that can be stored in a machine-readable format. If the
assumption regarding a testing tool does not hold at time of final
review of these guidelines, this checkpoint will be moved to the
Extended set of Checkpoints."


Proposed wording for Guideline 2.3


2.3 [CORE] Allow users to avoid content that is designed to flicker.

 

Editorial Note (June 10 2003): This Guideline is currently included in
the Core set of Guidelines because the WCAG WG expects that it will be
possible to test content for flicker and the result will be a flicker
rate in Hz that can be stored in a machine-readable format. If the
assumption regarding a testing tool does not hold at time of final
review of these guidelines, this guideline will be moved to the Extended
set of Guidelines.

 


Current wording for Checkpoint 2.3, SC 1


1. At least one of the following is true:

A. content was not designed to flicker (or flash) in the range of 3 to
49 Hz.

B. if flicker is unavoidable, the user is warned of the flicker before
they go to the page, and as close a version of the content as is
possible without flicker is provided.

 

Editorial Note:  We would like to include a third criteria here that
would state that a test that was conducted and the pages passed. No test
or tool exists yet though. We're looking into how such a test and/or
tool might be designed.


Proposed wording for Guideline 2.3, SC 1


1. At least one of the following is true:

A. content was not designed to flicker  in the range of 3 to 49 Hz (3-49
times per second).

B. if flickering content must be used, users are warned about the
flicker before they go to the page, and are informed that an alternative
version has been provided which approximates the original version as
closely as possible without flickering.

 

Editorial Note: We would like to include a third criteria here that
would state that a test that was conducted and the pages passed. No test
or tool exists yet though. We're looking into how such a test and/or
tool might be designed.


Current wording for Best Practice Measures for Checkpoint 2.3


1. animation or other content does not visibly or purposely flicker
between 3 and 49 Hz.

2. content that might create a problem has been tested [using XYZ tool];
only pages with unavoidable flicker remain and appropriate warnings
along with a close alternative presentation have been provided for these
pages.


Proposed wording for Best Practice Measures for Guideline 2.3


1. animation or other content does not visibly or purposely flicker
between 3 and 49 Hz.

2. content that might create a problem has been tested [using XYZ tool];
only pages with unavoidable flicker remain and appropriate warnings
along with a close alternative presentation have been provided for these
pages.


Current wording for Benefits of Checkpoint 2.3


* Individuals with photosensitive epilepsy can have seizures triggered
by flickering or flashing in the 3 to 49 flashes per second (Hertz)
range with a peak sensitivity at 20 flashes per second.

* Individuals who are easily distracted may not be able to focus on page
content with flicker occurring in the same visual field.


Proposed wording for Who benefits from Checkpoint 2.3 (Informative)


*        People with photosensitive epilepsy benefit from the absence of
flickering content.  For these individuals, seizures can be triggered by
flickering in the range between 3 and 49 times per second (3-49Hz), with
a peak sensitivity at 20 flashes per second.

*        People who are easily distracted may be able to concentrate
better if they are not distracted by content flickering in the visual
field.

 


Current wording for Examples of Checkpoint 2.3


[None listed]


Proposed wording for Examples of Guideline 2.3 


 (Informative)


[Examples needed]

 

 


"Good design is accessible design." 
Please note our new name and URL!
John Slatin, Ph.D.
Director, Accessibility Institute
University of Texas at Austin
FAC 248C
1 University Station G9600
Austin, TX 78712
ph 512-495-4288, f 512-495-4524
email jslatin@mail.utexas.edu
web http://www.utexas.edu/research/accessibility/
<http://www.utexas.edu/research/accessibility/> 


 

 
Received on Wednesday, 5 November 2003 17:37:51 GMT

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