Flashing or Blinking Content - new check

[shawna-slh]

Suggestion for check from Gregg V.: https://lists.w3.org/Archives/Public/wai-eo-editors/2015Jul/0044.html

Draft (thanks to Sharron!) at: http://www.w3.org/WAI/EO/Drafts/eval/checks#flash

Does this potential new check meet our Criteria for including a check? See: https://www.w3.org/WAI/EO/wiki/Eval_Analysis#Criteria_for_checks

If yes, comments on draft wording?

[davidberman]

[comments to be edited per <https://lists.w3.org/Archives/Public/w3c-wai-eo/2015OctDec/0004.html :-]

It sounds to me like it does meet the criteria. Perhaps it could also embrace Pause, Stop, Hide.

Regarding the draft,

• people need some guidance as to "bright enough"" so I think you should actually give them the official definition ... or we could say something of this nature instead of 3. (and perhaps 2. as well) : "The risk for seizures is actually only for images of a certain minimum brightness and size, however it is simpler for many developers to simply avoid all such flashing, rather than learning those details."
• regarding the box size instructions: ... 1024 x 768 is no longer a realistic size for many devices ... the entire one third/one fourth paradigm is outdated, as it assumes a 4x3 world. ... with small screen devices, pinch-zoom, full-screen video buttons, immersive goggles, 3-D movie theatres... the one third/one fourth measurement is likely no longer relevant, and so perhaps in Simple Checks we should simply avoid size altogether, and have them assume that any size is dangerous.
• Your "What to do" content (which would likely be clearer as "How to Check" in the entire document)... in order to distinguish it from a "How to Fix".) and your "What to check for" content seem wrongly intermingled. Have a read and see if you agree.
• "it may still pass but...": I think you may wish to tell them to either modify or remove the content OR choose to Learn More.
• change "EasyChecks" to "these Easy Checks"
• why do the Learn More lack a visible Expand/Collapse control (in both latest Chrome and Firefox)? (it's an issue throughout http://www.w3.org/WAI/EO/Drafts/eval/checks#flash ... whereas on http://www.w3.org/WAI/eval/preliminary#structure I do see visible Expand/Collapse. The "Expand All Sections" is also missing on the former, visible on the latter) [I realize this should perhaps be opened as a separate issue, but maybe it's something you guys have already covered.]

[iadawn]

Priority: Medium

Location: Flashing or Blinking content

Current wording/code:

People with photosensitive seizure disorders can experience a seizure if web content flashes at them within specific parameters.

Suggested revision:

People with photosensitive seizure disorders can experience a seizure if web content flashes at them within specific parameters. Flashing content can also cause difficulties for people with attention or visual processing disabilities.

Rationale: It is worth considering the impact of flashing content on other groups of people. Whilst not specifically mentioned in WCAG, it is touched on (lightly) in the Cognitive TF Gap Analysis.

[davidberman]

I agree. As per my existing GitHub comment, I suggest this could also embrace SC 2.2 Pause, Stop, Hide.

Regards, David

On 2015-10-02 10:40, Kevin White wrote:

This issue may extend beyond just photosensitive seizure disorders. Flashing content may also present a problem for people with disabilities associated with attention or cognition of perception.

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[davidberman]

I agree with the addition of "Flashing content..." and ALSO suggest perhaps we broaden this, as well as the main heading from "Flashing content..." to "Flashing or moving content...

[hkramer]

I like the addition of Flashing content can also cause difficulties for people with attention or visual processing disabilities" and agree with David's suggestion to include it to "Flashing or moving content."

[vuxcaleb]

Based on the feedback it sounds like this might be the consensus for the intro paragraph:

"People with photosensitive seizure disorders can experience a seizure if web content flashes at them within specific parameters. Flashing or moving content can also cause difficulties for people with attention or visual processing disabilities. This will be a problem only if all of the following are true:"

[sharronrush]

+1

[vuxcaleb]

The other proposal based on feedback is to simplify the check to remove any specific measurements beyond flashing/blinking three times per second. This is the entire updated copy proposed - notice the "What to check for:" section is removed:

Flashing or Blinking Content

People with photosensitive seizure disorders can experience a seizure if web content flashes at them within specific parameters. Flashing or moving content can also cause difficulties for people with attention or visual processing disabilities. This will be a problem only if all of the following are true:

1. The flashing occurs more than three times in any one second period;
2. the flash covers a sufficiently large area of the screen; and
3. the flash is bright enough.

What to do:

• Examine the screen display, looking for content that flashes or blinks more than three times in one second.
• If no content blinks or flashes at that rate, the page passes.

To learn more about flashing content

• Three Flashes or Below Threshold Understanding Success Criterion 2.3.1 for WCAG 2.0 (Level A)
• Free, downloadable Photosensitive Epilepsy Analysis Tool from the Trace Center at the University of Wisconsin

[yatil]

On first read, I like Caleb’s proposal. Seems quite practical to me!

[hkramer]

Clear and succinct.

[yatil]

Some – minor – wording changes to make it more succinct and align it more to other checks:

• Removing “within specific parameters” as we are describing those parameters later.
• Add “such as epilepsy” to give people who are not in accessibility lingo something they might vaguely know about.
• Try to de-double flash and flashing at the end of the first, and beginning of the second sentence.
• Remove repetition from ordered list.
• “What to do:” -> “What to check for:” as this is the actual check procedure and is used like that in the other checks.
• Tried to make the first point in “What to check for:” more active.
• We don’t use pass in other checks, so I used the “Check that …” formula from other checks.

Flashing or Blinking Content

People with photosensitive seizure disorders, such as epilepsy, can experience a seizure if web content flashes or blinks. Such content can also cause difficulties for people with attention or visual processing disabilities. This will be a problem only if all of the following are true:

1. The flashing occurs more than three times in any one second period;
2. it covers a sufficiently large area of the screen; and
3. is bright enough.

What to check for:

• Examine the screen and check that no content flashes or blinks more than three times in one second.

To learn more about flashing or blinking content

• Three Flashes or Below Threshold Understanding Success Criterion 2.3.1 for WCAG 2.0 (Level A)
• Free, downloadable Photosensitive Epilepsy Analysis Tool from the Trace Center at the University of Wisconsin

[nitedog]

Overall great rewrite @vuxcaleb! A few thoughts for your consideration (I don't feel strongly about them):

1. Something along the lines of "within specific parameters" is actually useful because some people may think that all blinking and moving content is bad - this is the very first sentence they read!
2. Adding "epilepsy" alone may be confusing. As far as I know this only applies to specific types of photosensitive epilepsy, not to all forms of epilepsy. Not sure if it is good to add this.
3. Suggest "people with attention and visual processing disabilities" - that is, "and" instead of "or", as both groups are affected. People may also have both these forms of disability.
4. Suggest "This problem occurs when the following applies:" - I think that "only" may be too absolute and "are true" seems like technical speak - our audience is probably less technical

[AndrewArch]

Looking good overall.

However, if we say "Flashing or moving content can also cause difficulties for people with attention or visual processing disabilities", which I like, then saying "This will be a problem only if all of the following are true" is not correct as people with attention or visual processing disabilities can find situations other than just 1+2+3 problematic.

One option might be to move "Such content can also cause difficulties for people with attention or visual processing disabilities." to after the list and reword as "This situation and other flashing or blinking content can also cause difficulties for people with attention or visual processing disabilities."

[James-Green]

I like the edit. I think this is the type of simplicity we should be aiming for.

[sharronrush]

agreed

On Thu, Sep 29, 2016 at 4:33 PM, James Green notifications@github.com wrote:

I like the edit. I think this is the type of simplicity we should be aiming for.

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[lakeen]

I agree with the re-write.

[vuxcaleb]

Great feedback and suggestions everyone. This following is where we landed - using suggestions from @yatil , @nitedog and @AndrewArch:

Flashing or Blinking Content

People with photosensitive seizure disorders, such as epilepsy, can experience a seizure if web content flashes or blinks. This will be a problem only if all of the following are true:

1. The flashing occurs more than three times in any one second period;
2. it covers a sufficiently large area of the screen; and
3. is bright enough.

Such content can also cause difficulties for people with attention and visual processing disabilities.

What to do:

• Examine the screen and check that no content flashes or blinks more than three times in one second.

To learn more about flashing content

• Three Flashes or Below Threshold Understanding Success Criterion 2.3.1 for WCAG 2.0 (Level A)
• Free, downloadable Photosensitive Epilepsy Analysis Tool from the Trace Center at the University of Wisconsin

[yatil]

Works for me! Well done.

[bakkenb]

Sorry to be a late comer to this issue discussion.

People with photosensitive seizure disorders, such as epilepsy, can experience a seizure if web content flashes or blinks. This will be a problem only if all of the following are true:

1. The flashing occurs more than three times in any one second period;
2. it covers a sufficiently large area of the screen; and
3. is bright enough.

When I read this wording quoted above, to me it sounded like we were saying that this is "a problem" when all these circumstances are true at the same time. The first may be "a problem" for many people even if it does not cover a large part of the screen, and/or if it isn't that bright.

The way I understand this SC to be written was to define some sort of threshold that was some level and combination of things that were agreed to be unacceptable. Just like the color luminosity ratio SC language. A 4.5:1 or higher ratio may be sufficient for some, but still may be "a problem" for others, but there needed to be some agreed upon threshold. It not "a problem only" if the ratio is lower than 4.5:1. For some it is still a problem at 5.5:1.

I think it would be wise to not say "This will be a problem only if all of the following are true," but to pull some language from the SC Note and say, "Flashing content that meets all of the following circumstances can interfere with a user's ability to use the whole page," or something similar.

I am not sure my example is even more clear. I think what I am trying to say is that I have a problem with the words "will" and "only". To me it would be better if it just said, "This can be a problem if all of the following are true:"

[yatil]

Thanks @bakkenb, I struggled with this sentence when I did my rewording above. What about:

“While flashing and blinking can be distracting in many circumstances, it is especially detrimental* if all of the following statements are true:”

(*There probably is a better word here.)

[vuxcaleb]

@bakkenb and @yatil is this what you were thinking? ... changes in bold.

People with photosensitive seizure disorders, such as epilepsy, can experience a seizure if web content flashes or blinks. This can be a problem if all of the following are true:

1. The flashing occurs more than three times in any one second period;
2. it covers a sufficiently large area of the screen; and
3. is bright enough.

Such content can also cause difficulties for people with attention and visual processing disabilities.

[bakkenb]

Thanks Caleb. It is better in my opinion. Reflects the SC a bit better. Interested in what others think.

[James-Green]

What if we solved Brent's concern and made it even more simple by removing the AND logic altogether.

People with photosensitive seizure disorders, such as epilepsy, can experience a seizure if web content flashes or blinks. This can be a problem if the flashing:

1. occurs more than three times in any one second period;
2. covers a sufficiently large area of the screen; and
3. is bright enough.

Such content can also cause difficulties for people with attention and visual processing disabilities.

[susanatx]

+1 to the version above.

[shawna-slh]

Great team work! A few additional simplification and tweaking ideas:

• How about switching it around so it emphasizes that the content is the problem, not the user.
• I mildly prefer to put the conditions together, rather than separating them with the list.
• I think we can simplify "… photosensitive seizure disorders, such as epilepsy" to to "photosensitive epilepsy". From brief research, I don't see other "photosensitive seizure disorders" besides epilepsy – and even if there are, this is intended to be an easy to read & understand example, not comprehensive coverage. (Or if there are others, we could say "…photosensitive epilepsy and other disorders." - but I don't think we need to.)
• Make be more clear than "cause difficulties". Maybe

Flashing or blinking content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders.

or

Moving content also makes it difficult for some people with attention deficit or visual processing disorders to focus and read.

• "attention and visual processing disabilities." doesn't work for me – "attention disabilities" doesn't seem right. I'm use to "attention deficit disorder".
• I think can simplify "…in any one second period" to "… in one second".
• I think don't need "Examine the screen" under "What to do". I think we can just have "What to check for:"
• I think we have to say more than just "Check that no content flashes or blinks more than three times in one second." – because you can have content that flashes more than that, but then it would have to be under other thresholds per the "general flash threshold or red flash threshold".
• I think we don't want to list "Free, downloadable…" It is already linked from the Understanding. And it's not worth going through the process of deciding what tools to link to or not.

So maybe:

Flashing or Blinking Content

Content can cause problems if it:

1. flashes more than three times in one second,
2. covers a large enough area of the screen, and
3. is bright enough.

Some flashing content can cause seizures in people with photosensitive epilepsy. Flashing or blinking content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders.

What to check for:

• Check that no content flashes or blinks more than three times in one second. If it does, do further evaluation as explained in the link below.

To learn more about flashing content

• Three Flashes or Below Threshold - Understanding Success Criterion 2.3.1 for WCAG 2.0 (Level A)

[vuxcaleb]

+1 @slhenry

[AndrewArch]

Seizures are (typically?) caused by the specific circumstances described - serious distraction and/or difficulty reading can be caused by this but also other (slower/smaller) flashing/blinking/moving content.

Having "Flashing or blinking content ... visual processing disorders." in the same para as the seizure discussion potentially implies that 'people with attention deficit or visual processing disorders' are only affected by 'flashes more than three times in one second' rather than any flashing or blinking.

I would suggest:

Flashing or Blinking Content

Content can cause seizures in people with photosensitive epilepsy if it:

1. flashes more than three times in one second,
2. covers a large enough area of the screen, and
3. is bright enough.

Flashing, blinking or moving content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders.

[shawna-slh]

[update: Andrew's comment above was very different when I replied below. So they're kinda outta synch. But I still think below. ;-]

Yeah. I had that thought. Another idea I had is:

Some flashing content can cause seizures in people with photosensitive epilepsy. Any moving content can make focusing and reading difficult for some people with attention deficit or visual processing disorders.

But the real issues is that that is mixing up two different things. Moving content is covered in SC 2.2.2.

I think we talked about that but I don't remember what we decided. @vuxcaleb did you find our past thoughts on that?

It seems like we probably want to delete that sentence all together from this Check. Then decide if we also want to add a separate check for Pause, Stop, Hide content...

[bakkenb]

I agree. Flashing or blinking is a different issue than moving content and they should remain separate.

[lakeen]

It seems as if the remaining issue is with the sentence below. It sounds as if it is included as a best practice and usability reminder. I think that removing "moving" works or removing the sentence entirely also works.

Flashing, blinking or moving content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders.

[dboudreau]

While I also think Andrew's point is relevant about how blinking/moving content can be a problem, it's really a different SC and therefore, should not be brought up in this particular check. I like the general way the check has turned out, think the suggestions are great and I'm comfortable with the version that James came up with based on all the previous discussions.

[susanatx]

100% agree with @dboudreau

[yatil]

• I don’t want to drag this on and I think the latest version is covering what we want to say. I support publication of this check as is, without integrating “moving content” for now.
• I think integrating moving content (and animation) in the easy checks is valuable but a different issue.
• We should not decide on (not) combining different issues for an easy check (or a Getting Started Tip) on the fact that they are in separate SCs – sometimes a combined check might find issues on different SCs, making it easier to follow the checks.

[dboudreau]

Eric,

Just a thought, but I think we should eventually try to make it so that each easy check refers to a quick tip, and vice versa.

/Denis

On Tuesday, 18 October 2016, Eric Eggert notifications@github.com wrote:

• I don’t want to drag this on and I think the latest version https://github.com/w3c/EasyChecks/issues/1#issuecomment-253689623 is covering what we want to say. I support publication of this check as is, without integrating “moving content” for now.
• I think integrating moving content (and animation) in the easy checks is valuable.
• We should not decide on (not) combining different issues for an easy check (or a Getting Started Tip) on the fact that they are in separate SCs – sometimes a combined check might find issues on different SCs, making it easier to follow the checks.

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[AndrewArch]

I didn't think we were tying each easy check to specific success criteria.

The issue is that flashing/blinking content (and by association, moving content - but I'm happy to leave that out for now) can cause seizures, but also causes focus and distraction issues for others. I think this still needs to be drawn out if we can.

[yatil]

@dboudreau Happy to discuss in another thread or on email, this one gets a bit overwhelming.

@AndrewArch I agree. But I also think we can refine this check or add another check later (in a reasonably short time frame). I created #23 to discuss an approach on moving/animated content.

[nitedog]

1. I agree with @yatil that we could/should have a separate check for moving content - this is really something different to look for
2. I support the suggested edit by @slhenry for publication
3. I don't mind adding the word "moving" in that last sentence, to say "Flashing, blinking, and moving content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders." - maybe also with cross-link to the new check when we add it

[AndrewArch]

I'm happy, let's call it done. (Thanks @yatil for starting #23 )

[vuxcaleb]

That was a great discussion and I really appreciate all the thoughts!

In an effort to close this issue please +1 or thumbs up the draft below (Shawn's draft):

Flashing or Blinking Content

Content can cause problems if it:

1. flashes more than three times in one second,
2. covers a large enough area of the screen, and
3. is bright enough.

Some flashing content can cause seizures in people with photosensitive epilepsy. Flashing or blinking content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders.

What to check for:

• Check that no content flashes or blinks more than three times in one second. If it does, do further evaluation as explained in the link below.

To learn more about flashing content

• Three Flashes or Below Threshold Understanding Success Criterion 2.3.1 for WCAG 2.0 (Level A)

[lakeen]

+1

[bakkenb]

+1

[AndrewArch]

+1

[sharronrush]

+1

On Wed, Oct 26, 2016 at 4:32 PM, Andrew Arch notifications@github.com wrote:

+1

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[yatil]

+1

[shawna-slh]

I think we want to having the moving content check, too - and then see how they fit. Specifically, I think we might not want "Flashing or blinking content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders." in this check because it will be covered by the moving content check?

[sharronrush]

It is OK in my opinion to have it in both places to reinforce the fact that flashing / blinking is about more than seizures

On Oct 27, 2016 9:43 AM, "shawn_slh" notifications@github.com wrote:

I think we want to having the moving content check, too - and then see how they fit. Specifically, I think we might not want "Flashing or blinking content also makes focusing and reading difficult for some people with attention deficit or visual processing disorders." in this check because it will be covered by the moving content check?

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[shawna-slh]

I drafted a Moving Content check for review and comment: https://github.com/w3c/EasyChecks/issues/23

I suggest we put both of these into the draft of the doc so we can see them in place to make decisions on that sentence above and on the carousal example. :)

[vuxcaleb]

Copy is updated in the Issue-1 pull request.

[shawna-slh]

Discussion moved to https://github.com/w3c/EasyChecks/issues/27