I think the key question was around refresh rate values and what they meant. This has digressed slightly. I had suggested milliseconds is a good measurement of time for the value. Whether or not it can cause epileptic fits is none of my concern. Looking at ugly ODF docs or other content has an equal wieght in this regard and the onus is on the author – we are not telling people what content to use.

I would like to ask for a decision – milliseconds as a measurement for refresh rates or ????

What is the alternative people are thinking of if not milliseconds?

Duane

On 18/07/08 11:52 AM, "robe...@us.ibm.com" <robe...@us.ibm.com> wrote:

The key point in my mind is that the nature of the problem ("a risk of causing an epileptic fit") may raise this from an accessibility issue to a safety issue.

ISO Directives, Part 2, section A.2.3 gives the following guidance:

"A.2.3 If health, safety aspects, the protection of the environment or the economical use of resources are relevant to the product, appropriate requirements shall be included. Otherwise, they may, in some countries, be made additional mandatory requirements which, if not harmonized, would constitute technical barriers to trade.

These requirements may need to have certain characteristics with limiting values (maximum and/or minimum) or closely defined sizes and, in some cases, even constructional stipulations (for example, to achieve non-interchangeability for safety reasons). The levels at which these limits are fixed shall be such that the element of risk is reduced as much as practicable."

So I think we should make some statement in the standard itself, not merely in a separate guidelines document, that defines how to use this feature safely.

Which leads me to the technical questions:

1) Surely, the table refresh itself is inoffensive, right? For example, an application could have a table refresh (fetch new data) but only display updates when some other condition was met. Or you might not have any GUI at all and the updates and recalc's trigger some action on the server.

2) Is any screen update faster than once every 3 seconds a problem? Or is it only certain styles of updates, the ones which noticeably "flash" because of poor redrawing, lack of double buffering or whatever? In other words is there any safe way of doing rapid screen updates?

3) Most display technologies are already redrawing at a fast rate. This is inherent in the graphics card/display technology. So very fast rates are OK? What is the range of rates where it is a problem?

4) How do we state this in the standard? Would something like this work: "Note: display devices which update information on the screen at rates between X Hz and Y Hz have been shown to prompt epileptic seizures in some people. ODF applications which refresh the display with each table refresh shall provide an option for the user to suspend the rendering of such refreshes." We could probably make a more general statement on refresh/animation/blink and place it in the conformance section of the standard.

Duane Nickull <dnic...@adobe.com> wrote on 07/18/2008 02:12:38 PM: