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Revising 2.4 to deal with timeout barriers

From: Adam Victor Reed <areed2@calstatela.edu>
Date: Wed, 23 May 2001 00:31:56 -0700
To: w3c-wai-gl@w3.org
Message-ID: <20010523003156.A29817@uranus.calstatela.edu>
I recently encountered a nasty timeout barrier on a major commercial
site. After going through several steps in an ordered sequence, I was
momentarily distracted and encountered a time-out that prevented me
from continuing, and had to re-start from the beginning of the sequence.
Our current 2.4 in http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-20010328.html
does not deal explicitly with timeouts. It reads

2.4 Give users control over how long they can spend reading or
interacting with content. Mechanisms that required a timed response
	* automatic refresh,
	* redirection,
	* flicker,
	* blinking
This can be satisfied by providing an option to deactivate automatic
updating, or to control the rate at which it occurs. User agents may
also offer control over this effect.  Note that flicker effects can
cause seizures in people with photoepilepsy.

I would like to propose the following instead:

2.4 Do not place limits on the time that a user may need to
understand or interact with content.  Eliminate:
	* demands that the user respond within a preset time
	* automatic refresh and delayed redirection
	* flicker, blinking, flashing, self-scrolling, or other
	  animation effects that cannot be disabled by the user.
Content must cooperate with user agent mechanisms for preventing
flicker, or for control of the rate at which it occurs. Note that
flicker effects can cause seizures in people with photoepilepsy.

				Adam Reed
Context matters. Seldom does *anything* have only one cause.
Received on Wednesday, 23 May 2001 03:32:04 UTC

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