If possible, it is always best to start with an accessible source document (e.g., in Microsoft Word) and export it to an accessible PDF. This way, if the document is edited later, the document’s accessibility features will still be intact. When the document is exported to PDF the accessibility features will be passed to the PDF.
However, if the original source document is not available, accessibility features can be added to the PDF using Adobe Acrobat Pro DC.
Checking PDF accessibility yourself
Consult the following checklist to review a PDF for accessibility. To complete each of the items in this checklist, you will need Adobe Acrobat Pro DC. The checklist specifically applies to Acrobat Pro DC.
WebAIM’s tutorial on PDF Accessibility is an excellent accompaniment to the current checklist.
NOTE: Modifying PDFs can have unpredictable results. Save often! (Saving multiple versions is recommended.)
Step 1. Does document have text?
How to test: Try selecting text using a mouse, or select all text using Edit > “Select All” from the Acrobat menu.
If No, this is an image file and is not accessible. Covert to text using View > Tools > “Recognize Text.”
Step 2. Is document tagged?
How to test: Go to File Properties (Ctrl+D in Windows, Command+D in Mac). In the bottom left corner of the Document Properties dialog, see the “Tagged PDF” field.
If No, this document needs to be tagged. Tags provide the structure on which accessibility is built. Add tags by selecting View > Tools > Accessibility > “Add Tags To Document.”
Step 3. Check for any lingering errors.
How to test: Run the accessibility checker that is built in to Acrobat Pro. Select Tools > Accessibility > “Full Check” then read the report and follow the prompts.
The report lists items in various categories such as Document, Page Content, etc. Each item is preceded by an icon indicating that the item either passes, fails, or requires manual inspection. Right-click on any item to see a list of options for fixing the problem or learning more about it.
This is the final step in our checklist, rather than the first step, because some documents generate dozens of errors that can easily be addressed with the first two steps. This way, the accessibility checker will report fewer problems and will be easier to read and work with.
To manually inspect the tag tree in Adobe Acrobat Pro, from the View drop-down menu select Show/Hide > Navigation Panes > Tags. This will display the tags in descending order from top to bottom. Visually inspect the tags to make sure the heading level structure is correct and elements are tagged accurately. For details, see Adobe’s Accessibility Repair Workflow for PDFs using Acrobat DC.