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Re: Level AA exceptions

From: Gregg Vanderheiden <gregg@raisingthefloor.org>
Date: Thu, 13 Aug 2015 23:20:18 -0500
Cc: IG - WAI Interest Group List list <w3c-wai-ig@w3.org>, GLWAI Guidelines WG org <w3c-wai-gl@w3.org>
Message-Id: <1C1FA3D5-D742-47B9-8565-5BFAD0464CFB@raisingthefloor.org>
To: Phill Jenkins <pjenkins@us.ibm.com>
Hi Phil

Being Essential was indeed one of the factors.    
However essential was not the dividing line between A and AA.   There are AA level provisions that are essential as well.    In fact there are AAA level provisions that are essential but that are in Level AAA because it was not possible to meet them for all web sites and types of content that the SC would apply.   So Essential is not a criteria by itself for an SC being in any level.    None of the items in the list was determinant for level A or AA provisions. 

How were the levels decided for each SC?   
As the Understanding WCAG 2.0 doc says - it was based on many factors - some of which are listed below. 

All of these factors in the list were considered by the working group in deciding which level something went into.  There was never one factor.   And there is no formula.  The level the SC ended up in was the level that the group reached consensus on for that provision -  given the different considerations below and more.  The list below are the ones identified in asking the group what was considered.    But it is not likely that is is exhaustive.

So the answer to  “why was a particular SC placed in level A or AA or AAA?”  is:  
		  Because it was the consensus of the Working Group that it be placed there. 
And the answer to  “Bhat did they consider in placing the provision there?”  is:  
		The list in Understanding WCAG 2.0 gives the major considerations we identified but there are likely others as well. These are the ones the working group identified in answering this question. 

So what is the difference between A  and AA and AAA.  Think of them as a measure of accessibility as in    1 inch  2 inches and 3 inches.   each one is longer than the one  before.     A is so accessible. AA is more accessible and AAA is still more accessible.       People can decide how long (inches ) is long enough for a nail for example in order to hold up a beam.     Or how accessible something has to be in order to meet a minimum accessible standard.      Most have decided that A was not enough and that AA should be required by looking at what was in A and AA.    The working group recommended against requiring AAA for all content because there are some provisions there than cannot be applied to all content.  And there are other factors for others that put them in this category.   But there are places that require AAA for some parts of a site - or for some types of content - where they could apply there.   And there are those who reach AAA because they can for their site and they want to go further than Level AA. 

Hope this helps.

(PS this is from my personal knowledge and memory of the working group and the proceedings - and is not an official statement of the working group)  
(PPS  the PS  is my standard disclaimer for anything that is from my recollection and understanding and not reviewed and vetted by the working group current and past).


Gregg Vanderheiden

> On Aug 13, 2015, at 7:41 PM, Phill Jenkins <pjenkins@us.ibm.com> wrote:
> As more and more policies and regulations adopt both level A and AA and thereby place more of the responsibility and burden on the web content, the notion of the difference between and rationale for having Level A and AA is getting lost and misunderstood.   
> Is there still general consensus that there are interacting issue that need to be considered when applying Level AA Success Criteria to all web content and web applications?   
> See Understanding Levels of Conformance <http://www.w3.org/TR/UNDERSTANDING-WCAG20/complete.html#uc-levels-head> http://www.w3.org/TR/UNDERSTANDING-WCAG20/complete.html#uc-levels-head <http://www.w3.org/TR/UNDERSTANDING-WCAG20/complete.html#uc-levels-head> 
> "The Success Criteria were assigned to one of the three levels of conformance by the working group after taking into consideration a wide range of interacting issues. Some of the common factors evaluated when setting the level included:
> whether the Success Criterion is essential (in other words, if the Success Criterion isn't met, then even assistive technology can't make content accessible)
> whether it is possible to satisfy the Success Criterion for all Web sites and types of content that the Success Criteria would apply to (e.g., different topics, types of content, types of Web technology)
> whether the Success Criterion requires skills that could reasonably be achieved by the content creators (that is, the knowledge and skill to meet the Success Criteria could be acquired in a week's training or less)
> whether the Success Criterion would impose limits on the "look & feel" and/or function of the Web page. (limits on function, presentation, freedom of expression, design or aesthetic that the Success Criteria might place on authors)
> whether there are no workarounds if the Success Criterion is not met."
> So, that says to me that Level AA Success Criteria are not "essential",  some may not always apply to all types of content (e.g. contrast on complex visualizations), some may require skills that cannot always be reasonably achieved by the content creators (e.g. video descriptions), and that it may impose limits on the "look & feel" and/or function (e.g. more images / less text), although I believe those success criteria imposing limits were identified as Level AAA. 
> In other words "...you are advocating that AA success criteria should have more 'wiggle room' than Level A Success Criteria" ? 
> Yes, because the working group reached consensus on making it level AA instead of Level A because of the wide range of interacting issues.  However, none of the supporting documents (Note1) have listed the specific "interacting issues" per individual success criteria for why it was assigned level AA or level AAA instead of level A.  Yes there are exceptions listed where appropriate for both Level A and AA Success Criteria, but those are not the all the issues discussed that caused the criteria to be assigned as AA instead of A.  Most if not all the "interacting issues" are logged deep in the e-mail archives of the working group.   
> So, should there be documentation added on the rationale for why a success criteria was assigned level AA (instead of A or AAA) to help practitioners better understand "how to apply level AA success criteria" as compared to applying Level A success criteria?   For example, should a non-normative section be added titled  "Rationale for assigning this SC to Level AA" be added  to the Understanding WCAG 2.0 guide? 
> Note 1: Supporting documents: 
> 1. Understanding WCAG 2.0 http://www.w3.org/TR/UNDERSTANDING-WCAG20/complete.html <http://www.w3.org/TR/UNDERSTANDING-WCAG20/complete.html> 
> 2. How to Meet WCAG 2.0 http://www.w3.org/WAI/WCAG20/quickref/ <http://www.w3.org/WAI/WCAG20/quickref/> 
> ____________________________________________
> Regards,
> Phill Jenkins,
Received on Friday, 14 August 2015 04:20:50 UTC

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