An accessible PDF is a well-formed Tagged PDF.
You start with the proper authoring application that has tag management (there are not that many - discussed below).
Your Tagged output PDF must be post-processed with Acrobat Pro.
You evaluate the post-processed PDF.
If satisfactory, you deploy the well-formed Tagged PDF.
Adobe Reader or Acrobat (from 8.x forward) both provide the read out loud feature (ROL).
While this is not equivalent to a full assistive technology (AT) application it can be useful for simpler narrative content.
However, PDF page content consists of graphic objects (text included) that are painted to the page in a sequence/order that is "machine" centric rather than human centric.
So, the raw print stream's read order can jump around.
(Look over ISO 32000-1 Forward paragraph 2 & Sections 8.1 & 8.2 to get a feel for what "PDF" is (& isn't).)
PDF became an ISO Standard in 2008. This is currently ISO 32000-1. ISO 32000-2 is expected to be out in 2012.
In terms of accessible PDF, ISO 14289-1 is expected to be out in 2012.
ISO 14289 will define/describe the requirements for accessible PDF.
Adobe introduced "Tagged PDF" with Acrobat 5.x (PDF version 1.4) "Full" release.
For Acrobat 5.x this was an add-on that you took from the install CD-ROM.
Since then "Tag" creation, management, etc. has been included with the install of:
(n.b., PDFMaker provides "tag management")
--| Acrobat 6.x Pro (PDF version 1.5)
--| Acrobat 7.x Pro & 3D (PDF version 1.6)
--| Acrobat 8.x Pro & 3D (PDF version 1.7)
--| Acrobat 9.x Pro & Extended (ISO 32000 & Adobe Supplement BaseVersion 1.7, ExtensionLevel 3)
--| Acrobat X Pro (ISO 32000 & Adobe Supplement BaseVersion 1.7, ExtensionLevel 3)
If the PDF is a well-formed Tagged PDF then ROL works its way down the structure tree (which can be viewed in Acrobat Pro's Tags panel).
A well-formed Tagged PDF (built to comply with ISO 32000 currently & going forward built to comply with ISO 14289 / ISO 32000 will, in fact meet current Section 508 criteria and Section 508 Refresh criteria.
Actually, it will met more rigorous criteria (Section 508, compared to other nations' requirements is somewhat anemic).
For English, ROL will read left to right; top down.
Not very useful for understanding tables and some other aspects of more developed content.
AT uses the structure tree to convey the PDF's logical hierarchy and semantic content flow to users.
So, a well-formed Tagged PDF is an essential for users of AT.
Section 14 of ISO 32000-1 provides discussion of logical structure and tags.
An ISO approved copy is at Adobe:
In a nut shell, you'd want to provide a well-formed Tagged PDF.
To effectively consume a downloaded well-formed Tagged PDF end-users will want to use AT (NVDA (free, open source), JAWS, etc.) rather than Adobe Reader / Acrobat ROL.
As to Ted's PDF Bible.
I've got 'em on my bookshelf. Most excellent global references for all things Acrobat.
However, to deploy well-formed Tagged PDF requires more detailed references.
There is the up front authoring. Content must be mastered so as to support output of a well-formed Tagged PDF.
There is the requisite post-processing of the PDF with Acrobat Pro.
There is the requisite understanding of what the tags/elements are & how to properly use them.
There is the need for specific "how-to" with examples.
As to a "simple site" - - well, ahhh, "simple" precludes anything of usable worth, eh.
A search on variations of "accessible PDF" will provide links to resources that provide "how-to".
One resource is the Accessiblilty Forum at the Acrobat User Community.
AUC Accessibility Forum
An older thread there has links to Adobe "how-to" for various Acrobat releases.
As the core of Acrobat's accessibility features are largely the same since Acrobat 5.x older how-to documents are still useful.
For the most part, the most definitive discussions of the how-to & the why are in older Adobe documents.
Of course, stuff comes & goes out on the web so the links may or may not be functional.
(n.b., you'll have to copy-paste the URLs into a browser's address bar)
However, a search on a document's title may provide an alternative link.
If not, send me a forum PM.
Remember that the key to success (for a well-formed Tagged PDF) is in the authoring.
Proper authoring with an application that provides adequate Tag management is critical.
--| Adobe FrameMaker or InDesign with Acrobat Pro
--| MS Word with Acrobat Pro (for PDFMaker & ability to perform requisite post-processing of the PDF) for pre Office 2007
--| MS Word 2007 / 2010 have a Save As PDF feature that can provide tag management -- but Acrobat Pro is still needed to perform requisite post-processing
--| Open Office (& Acrobat Pro for requisite post-processing)
Message was edited by: CtDave
WOW, what an awesome answer!
I have read it twice and there is much to go research and digest. This is exactly what I was looking for to find a starting point to assist customers. My testing was only sporadically successful and now I know where to look to validate our PDFs and develop a process or procedure for our employees to make sure our customers have access to the information they need.
You REALLY thought this through, took a big subject; broke it down into understandable blocks and freely shared you considerable experience.
I assumed ISO documentation available since PDF became a multi-vendor file format years ago as you mentioned.
This forum is very fortunate to have someone as knowledgeable as you.
Many Internet customers hopefully will benefit from your great information.
I cannot thank you enough CtDave.
Some additional resources:
W3C's "PDF Techniques fro WCAG 2.0" at — http://www.w3.org/WAI/GL/WCAG20-TECHS/pdf.html
(Older but informative) W3C's "PDF Techniques for Web Content Accessibility Guidelines 1.0 and 2.0" —
Articles by Duff Johnson (U.S. Committee Chair ISO/DIS 14289-1) —
Something to keep in mind.
The "Normative Document" for Tagged PDF (which supports Accessibility, Export to other applications, Reflow for Mobile Devices) is currently ISO 32000.
When published by ISO the ISO 14289-1 standard will be (in context of ISO 32000) the "Normative Document" for Accessible PDF.
Upon release of ISO 14289 it is anticipated that AIIM will provide a Guide at —