Adobe Systems has a new post on the Adobe Accessibility blog about PDF/UA and its relationship to WCAG 2.0, the web content accessibility guidelines published by the W3C.
WCAG 2.0 and PDF/UA discusses the background of PDF/UA and describes how Adobe Systems understands the way in which the two documents, PDF/UA and WCAG 2.0, work together.
PDF/UA was developed with not only key technical particulars of PDF such as font handling in mind, but the peculiar use-cases of PDF as well. PDF/UA systematically addresses each of PDF's features and details how they must be addressed to be made accessible. Of the existing WCAG 2.0 PDF Techniques for this purpose, Adobe says:
"... the PDF techniques, while useful, do not presently represent a complete set which encompass all technical requirements for accessibility in all PDF documents. This is where PDF/UA provides help."
To make it completely clear, Adobe goes on to say:
"PDF/UA provides normative technical specifications for the use of the PDF format, defining proper structure and syntax to enable reliable access."
One thing that's critical to understand about PDF/UA is that it's not sufficient - by itself - to conform to WCAG 2.0. PDF/UA is just a technical specification for accessible PDF - nothing more. As Adobe puts it:
"...WCAG 2.0 has additional requirements which require an authors attention."
Indeed: it's the case. From time-based media (guideline 1.2), scripting and actions (e.g. success criteria 3.2.1 and 3.2.2), and including certain types of content (e.g. success criteria 2.4.4), WCAG 2.0 includes a number of requirements that go beyond PDF/UA.
Adobe Systems makes it plain that they fully support PDF/UA and intend to use and promote it in their PDF authoring tools. They also note that:
"Adobe also plans to support the conforming Reader requirements, which are part of PDF/UA."
Read the full text of Adobe's statement on PDF/UA.