Adobe Acrobat XI - Manual (Page 481)

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Accessibility, tags, and reflow
Last updated 1/14/2015
The conversion process doesn’t always correctly interpret the document structure for the combined PDF, because the
files being assembled often use different formats. Use Acrobat Pro to create an accessible PDF from multiple
documents.
When you combine multiple PDFs into one tagged PDF, it is a good idea to retag the combined document. Combining
tagged and untagged PDFs results in a partially tagged PDF that isn’t accessible to people with disabilities. Some users,
such as those using screen readers, are unaware of the pages that don’t have tags. If you start with a mix of tagged and
untagged PDFs, tag the untagged files before proceeding. If the PDFs are all untagged, add tags to the combined PDF
after you finish inserting, replacing, and deleting pages.
When you insert, replace, or delete pages, Acrobat accepts existing tags into the tag tree of the consolidated PDF in the
following manner:
• When you insert pages into a PDF, Acrobat adds the tags (if any) for the new pages to the end of the tag tree. This
order occurs even if you insert the new pages at the beginning or the middle of the document.
• When you replace pages in a PDF, Acrobat adds the tags (if any) from the incoming pages to the end of the tag tree.
This order occurs even if you replace pages at the beginning or the middle of the document. Acrobat retains the tags
(if any) for the replaced pages.
• When you delete pages from a PDF, Acrobat retains the tags (if any) of the deleted pages.
Pages whose tags are out of order in the logical structure tree can cause problems for screen readers. Screen readers read
tags in sequence down the tree, and possibly do not reach the tags for an inserted page until the end of the tree. To fix
this problem, use Acrobat Pro to rearrange the tag tree. Place large groups of tags in the same reading order as the pages
themselves. To avoid this step, plan on inserting pages to the end of a PDF, building the document from front to back
in sequence. For example, if you create a title page PDF separately from the content, add the content PDF to the title
page PDF, even though the content document is larger. This approach places the tags for the content after the tags for
the title page. It’s unnecessary to rearrange the tags later in Acrobat Pro.
The tags that remain from a deleted or replaced page don’t connect to any content in the document. Essentially, they
are large pieces of empty tag tree sections. These redundant tags increase the file size of the document, slow down
screen readers, and can cause screen readers to give confusing results. For best results, make tagging the last step in the
conversion process. Use Acrobat Pro to delete the tags of deleted pages from the tag tree.
For more information, see Create merged PDFs .
About tools for creating accessible PDF forms
Adobe offers several tools for the creation of accessible PDF forms:
Acrobat Pro, Acrobat Standard Use one of these applications to open untagged or tagged PDF forms (except PDF forms
that are created from LiveCycle Designer) to add fillable form fields, such as text boxes, check boxes, and buttons. Then
use the application’s other tools to make the form accessible. Add descriptions to form fields, tag untagged forms, set
the set tab order, manipulate tags, and perform the other PDF accessibility tasks.
LiveCycle Designer (Available in Acrobat Pro) Use this product to design and build new forms or to import untagged
PDF forms and make their form fields fillable and accessible. You can deploy forms in tagged PDF, XML, and other
formats from LiveCycle Designer. Once you create or edit an Acrobat form in LiveCycle Designer, it becomes a
LiveCycle Designer file. It is no longer a PDF that you can edit or manipulate in Acrobat. Both Acrobat and Reader can
open and read PDF forms that you create fromLiveCycle Designer. These PDF forms, however, don’t include
permissions to modify the file. Therefore, use LiveCycle Designer only for PDFs that are intended to contain only form-
based information. Don’t use it to add form fields to a document that combines pages of narrative with an occasional
page that has form fields. In this case, use Acrobat Pro to add the form fields. Then complete the accessibility tasks for
the rest of the document content.