- From: Adam Victor Reed <areed2@calstatela.edu>
- Date: Wed, 23 May 2001 10:31:24 -0700
- To: w3c-wai-gl@w3.org
Anne, The site with the timeout was http://www.dell.com/refurbished. I am not a neurologist, but I did witness a seizure from stroboscopic light in an undergraduate physics lab, and that strobe flickered at a rate not very different from what I have seen on many web pages. Note that my not having witnesed actual seizures from video displays may be a result of living in North America. According to http://www.scils.rutgers.edu/~beam/mm/photosensitivity/links.htm "Photosensitivity seizures are a bigger concern in the United Kingdom than they are in the U.S., because UK electrical current cycles at a slower rate than ours. This slows the flicker of the television there slightly, making television viewing more likely to provoke a seizure." Your point, that the inclusion of animations may be unobjectionable if motion and flicker can be prevented in the user agent, is well taken. I think that the following revision takes care of this: 2.4 Do not limit the time that a user may need to understand or interact with your content. Eliminate: * demands that the user respond within a preset period * automatic refresh and delayed redirection * motion and flicker that cannot be prevented by the user. Content must cooperate with user agent mechanisms for disabling movement, or for control of the rate at which it occurs. Note that flicker effects can cause seizures in people with photoepilepsy. -- Adam Reed areed2@calstatela.edu Context matters. Seldom does *anything* have only one cause.
Received on Wednesday, 23 May 2001 13:34:35 UTC