TIP 59: Basic Document Tagging
Some program features used to enhance accessible use, such as articles and reflow, don't work properly or predictably unless a document is tagged, which means it has a logically defined structure. Tags are invisible and are a part of the document's information. They define relationships among elements in the document, including tables, lists, images, and text.
Planning Documents for PDF Accessibility
The key to successful tagging of a document as well as making it comfortable for a user working with a screen reader is to use your source programs' features efficiently. Plan ahead. Here are a few examples: Configure the document pages correctly. Don't add blank lines to make a space. Check the styles attached to inserted material such as images and charts. Group tables and charts or convert them to an image before conversion to prevent creating individual tags for each line and word segment.
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Tagging can be done in the source document (if you're using a PDFMaker) or in Acrobat. To tag a document using a PDFMaker, like the one used in Microsoft Word, choose Adobe PDF > Change Conversion Settings. The Change Conversion Settings dialog opens to the Settings tab. In the Applications Settings section of the Settings tab, select the option Enable accessibility and reflow with Tagged PDF, and then click OK. Click Convert to Adobe PDF or choose Adobe PDF > Convert to Adobe PDF. Word creates your PDF file. Open the document in Acrobat and choose View > Navigation Tabs > Tags to display the Tags panel. Click the Tags icon to display the document's tags in a hierarchy (Figure 59). The figure shows a section of the Tags panel for a table. You see the parent tag Table contains tags for the <Tbody> (table body,) which contains tags for the table rows <TR>, which contains tags for table cells <TD>, which contains tags for column heads, and finally the cell's text.
Figure 59. A tagged document displays its tag content in a hierarchy.
Many document-creation programs don't offer tagging options. You can easily add tags from within Acrobat:
1. | Check for preexisting tags by choosing Advanced > Accessibility > Quick Check. The Accessibility Quick Check looks for a document structure (tags). An untagged document displays a message stating the document isn't structured and may cause a problem with reading order. Click OK to close the Quick Check results message.
A Structure and Tags Aren't Equal
Some programs create a structured document that often is fine for reading in Acrobat. For example, creating a Word document using styles in a heading hierarchy is an example of a structure. A structure doesn't provide some of the qualities in an accessible document such as word spacing; you must tag a document in order to make it compliant with accessibility standards. |
| 2. | Choose Advanced > Accessibility > Add Tags. Acrobat processes the document and adds tags. An Accessibility Report displays in the How To pane area at the right of the document pane in the program window. Refer to the following tip for information on working with tags and reports. | 3. | Check the document again by selecting Advanced > Accessibility > Quick Check. The new message will state there are no accessibility problems with the document, meaning it is tagged. | 4. | Choose File > Save to save the document with its tagged structure. |
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