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From: Wayne Dick
Date: Dec 7, 2009 10:33PM

This is primarily to Andrew Kirkpatrick, but I
think my interpretation may be instructive for
anyone who interprets standards.

If you are part of an educational institution you
must show a reasonable effort to achieve “equally
effective access” to information. If your site
fails a key provision of a well recognized
standard, and the lack of that provision excludes
a well defined and protected disability group,
like moderate low vision, then a 504 complaint to
the Office for Civil Rights will likely succeed.

I was sloppy in my original analysis.

As Andrew pointed out, the issue is Accessibility
Support. This is a part of WCAG 2.0 Conformance,
and it is pretty tricky. It basically says that
if you include a medium in your web page then you
can only claim WCAG 2.0 Conformance at a given
Level (A, AA or AAA) if your medium supports a
reasonably attainable assistive technology at the
given conformance level. If no such attainable
assistive technology exists then the medium is not
accessibility supported. To meet conformance, a
site that includes a medium that is not
accessibility supported, must provide an
equivalent alternative medium that has
accessibility support at that desired conformance
level.

There is no doubt that Guideline 1.3 and Criteria
1.3.1 cover the text level. The concept of
information and relationships with no dependency
on visual style is not confined to the tag level
(table, list, form etc.). It refers to
information, relationships and style with no
qualification. Given the precision of WCAG 2.0,
that language was no accident.

Most of the examples in WCAG are directed at the
semantic significance of tags because many sighted
developers lack the life experience to understand
the importance of semantic markup at the tag
level. To inexperienced developers with full
sight, groupings created by tags and the visual
styles that convey these groupings are the same
thing. This choice of examples, does not mean
that all critical information and relationships
occur at the tag level.

Space indicates separation and sequential
relationships between letters, words and lines.
If these visual cues are imperceivable the
semantics of separation and sequential
relationships are lost. Now, as Andrew pointed
out, the programmatically determinable information
is present in the PDF document, but to date there
is no atainable assistive technology to present
this material in a form that is needed by moderate
low vision.

Likewise, characters (letters, numbers and
punctuation) are important semantic information.
It is difficult to read with reduced perception of
characters. If they are presented in the wrong
font family, they are very difficult to perceive.
Letters are information, and font family is
style. These fall under the scope of the
adaptability guideline.

The need for these transformations has been well
documented for at least a decade. Much work on
low vision includes these style traits as
important factors for supporting reading with low
vision.

HTML and most word processing formats are
accessibility supported regarding these style
traits. HTML with style sheets support spacing at
all levels as well as font families. Word and
Open Office support style templates that include
font family, letter, word and line spacing. A
document that is developed with proper structure
can be transferred from one CSS style or word
processing template to another in one step
creating all typographic changes needed. This can
be done without loss of semantic structure. There
are data formats that are accessibility supported
regarding text presentation. For HTML and word
processors, this helps reading and writing. I
prepare documents in one style (HTML) or one
template (word processing) for my own use. This
format is very annoying to people with full sight.
So, I publish the document with another style or
template. When I read HTML, I change the style.
When I receive a Word or Open Office document for
review, I pull it into my template and read. If
that fails I use the new write as Daisy ad-on, and
restyle the Daisy.

My issue is this. Guideline 1.3 and Criterion
1.3.1 are not accessibility supported by any PDF
document at this time. 1.3 and 1.3.1 apply at the
text level, and no attainable assistive technology
exists to transform text style completely for PDF.
This, to me, means that one cannot use PDF and
conform to WCAG 2.0 Level A at this time without
providing an equivalent document that is
accessibility supported. We know that HTML is
accessibility supported so an option exists.

I am not concerned with badly written documents.
They are just a mess, and we know how to teach
people to avoid this situation. My issue is that
there is no way to write PDF documents in a form
that is accessibility supported –even model
documents.

I would really like to thank the group for this
discussion. It has clarified my thinking. I do
not think accessibility support for PDF needs to
be far away. Andrew’s comments have really
confirmed my belief that this is true. Right now,
I think to meet WCAG 2.0 Level A you need
alternative file formats until the accessibility
support for moderate low vision is in place.

If you are an educational institution this is very
important because you will have a hard time
proving your PDF files provide equally effective
access. Remember, a student with a plausible
complaint can call down a full OCR audit on your
campus, and they do not have to spend anything to
do it. Adobe is not liable for this problem, the
campus or system is liable for the damages. I
will be encouraging my system, the California
State University, to take a cautious
interpretation of accessibility support for PDF.
That was my primary reason for starting this
discussion. In the current budget climate few
educational systems can afford to take another hit
for tens of millions of dollars.

This is the last I will write on PDF on WebAIM for
a long time. The discussion has clarified my
thinking. Andrew, I am interested in giving
feedback to the reader group on the needs of
moderate low vision regarding PDF. I thank you
for your thoughtful comments. To those who asked
for more direct communication I’ll get to you
soon. I’ve saved this discussion.

Sincerely Wayne

Reference: The conformance requirement is WCAG 2.0
Conformance: Conformance Requirement 4.
“4. Only Accessibility-Supported Ways of Using
Technologies: Only accessibility-supported ways of
using technologies are relied upon to satisfy the
success criteria. Any information or functionality
that is provided in a way that is not
accessibility supported is also available in a way
that is accessibility supported. (See
Understanding accessibility support.)”