W3C home > Mailing lists > Public > w3c-wai-ig@w3.org > July to September 2012

RE: WCAG Techniques are informative [was: Programmatic association of generic link text]

From: Jonathan Avila <jon.avila@ssbbartgroup.com>
Date: Tue, 4 Sep 2012 09:58:41 -0400
Message-ID: <b9d9a514eb9ad1f209fb650f2e83f1f5@mail.gmail.com>
To: w3c-wai-ig@w3.org
[Shawn Wrote]
> You do not have to use the sufficient techniques to meet WCAG
> Web content could even fail a particular technique test, yet still meet
WCAG a different way.

I agree with this - however, the latter portion regarding failures I
believe is very confusing to those trying to achieve or/and confirm
conformance.   The community needs documentation to help clarify the
intent of the SC.  For instance:

SC 1.4.3 states "Contrast (Minimum) The visual presentation of text and
images of text has a contrast ratio of at least 4.5:1, except for the
following: (Level AA)

A non-normative technique associated with the SC, F24: states "Failure of
Success Criterion 1.4.3, 1.4.6 and 1.4.8 due to specifying foreground
colors without specifying background colors or vice versa"

While the technique is very good and aims to assist when user specified
styles are used- the SC doesn't say anything such as "with user specified
styles" or anything that would seem to require viewing with anything other
than the user agent's default display method.   So if a website does not
specify the foreground and background colors but the currently specified
foreground text on the default user agent color is white, does it meet the
SC?

The Understanding WCAG 2 document states " Another support category is
"Common Failures", which describe authoring practices known to cause Web
content not to conform to WCAG 2.0."

This would indicate to me that a Failure is a Failure and is more explicit
than a sufficient technique -- which is just one method of meeting a SC.

Jonathan


-----Original Message-----
From: Shawn Henry [mailto:shawn@w3.org]
Sent: Tuesday, September 04, 2012 9:21 AM
To: w3c-wai-ig@w3.org
Cc: Roger Hudson
Subject: WCAG Techniques are informative [was: Programmatic association of
generic link text]


On 9/4/2012 5:06 AM, Roger Hudson wrote:
> ...
>
> However, on a wider point - I am becoming increasingly concerned by
> the tendency to see Techniques as rules. Let us not forget, Techniques
> are informative, whereas Principals, Guidelines and Success Criteria
> are normative.

Thanks for the reminder of this, Roger.

As stated in a blog post earlier this year[1]:

First, understand that the basis for determining conformance to WCAG 2.0
is the success criteria from the WCAG 2.0 standard - not the techniques.
The Techniques document provides guidance that is "informative". You do
not have to use the sufficient techniques to meet WCAG. Web content can
use other ways to meet the WCAG success criteria. Web content could even
fail a particular technique test, yet still meet WCAG a different way.
Also, content that uses the published techniques does not necessarily meet
all WCAG success criteria.

To learn more about the techniques, please see:
* About the Techniques section of How to Meet WCAG 2.0: A customizable
quick reference... <http://www.w3.org/WAI/WCAG20/quickref/#about-techs>
* Sufficient and Advisory Techniques section of Understanding WCAG 2.0
<http://www.w3.org/TR/UNDERSTANDING-WCAG20/intro.html#introduction-layers-
techs-head>

Best,
~Shawn

[1] http://www.w3.org/QA/2012/01/wcag_techniques_learn_more.html


-----
Shawn Lawton Henry
W3C Web Accessibility Initiative (WAI)
e-mail: shawn@w3.org
phone: +1.617.395.7664
about: http://www.w3.org/People/Shawn/
Received on Tuesday, 4 September 2012 14:01:15 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 5 February 2014 07:13:30 UTC