PDF Accessibility Reading Order

Hi,

	I’m in a position where I have to check several PDFs for compliance to WCAG 2.0.  I use the PDF Techniques for WCAG 2.0 site (http://www.w3.org/WAI/GL/WCAG20-TECHS/pdf.html) to check for sufficient techniques.  These techniques seem to be aimed at people who create PDFs.  I do not create.  I merely check other author's PDFs.  I use Adobe Acrobat Pro X to check the PDFs.

	But one technique has me quite confused as to what to check.  PDF3: Ensuring correct tab and reading order in PDF documents.   There are two parts to that:  1) Tab Order, and 2) Reading Order.

	Tab order is easy.  Tab through the form and see if it goes in order.

	Reading Order is confusing.

	First, let me say that 99% of the PDFs that come into my inbox do _not_ allow me to reflow (CTRL+4).  That menu option is greyed out.  So I use the Order panel and Tag panel.

	If I run NVDA and open up a PDF, NVDA reads the PDF in Tag order.  However, if I select one element, and navigate with my arrow keys, NVDA follows the order in the Order panel sometimes, and other times the Tag order.  If I use Adobe's Read Out Loud function and use select "Read to End of Document" or "Read this Page Only", it follows he Tag order.   But, if I navigate using my keyboard using my arrow keys, it seems to Read Out Loud in the order in the Order panel.

	If I go File -> Save As... -> More Options -> Text (Accessible), it gets saved in the Tag order.

	On the W3C site (http://www.w3.org/WAI/GL/WCAG20-TECHS/pdf.html#PDF3) it seems to imply I need to check the order in the Order panel.

	If I search the web, other sites and documents have conflicting information.  Some say it's all about Tag order.  Others just tell you how to fix the order in the Order panel.

	Again, on the W3C site, I see the following:  "The reading order of a PDF document is the tag order of document elements, including interactive elements."  (http://www.w3.org/WAI/GL/WCAG20-TECHS/pdf.html#PDF3-description).  That seems to imply that the reading order _is_ the Tag Order.  If the reading order _is_ the Tag order, why is there one panel for reading order, and another for tag order?  Shouldn’t they be the same?

	Everything I've read, all taken together _implies_ the order in the Order panel should match the Tag order.  I have not seen this explicitly stated anywhere.


	So, to ensure greater accessibility, should I be checking the Order panel, the Tag Order, or both?  Do I make sure the order in the Order panel matches the Tag Order?
	

	Thanks for your help!


	Andrew Nordlund

Received on Wednesday, 11 July 2012 15:20:36 UTC