Many websites provide important information in PDF documents but they are often not accessible, which means that readers with disabilities miss the information. Most PDFs can be made accessible in a small number of steps that will seem familiar if you have created accessible HTML.
- Use an authoring tool that generates tagged PDFs. Many tools do this, including Microsoft Word, InDesign, OpenOffice.org Writer, Adobe Framemaker, and others. Tagged PDFs support a set of standard structure types and attributes -- text, headings, lists, tables, and images with text alternatives -- that allow page content to be accessible to assistive technologies. For screen readers, it's also important that you specify the language of the document.
- Use your authoring tool's built-in formatting features such as headings, lists, tables, hyperlinks, etc. to create a document that is structured logically and clearly. This is a best practice for any document, in any format and the structure is important for accessible PDFs.
- Generate a tagged PDF using your authoring tool. You may have to change some settings to specify tagging. The conversion process maps the authoring tool's structural elements to PDF tags to create an accessible PDF document.
- Use Adobe Acrobat Pro to run a Full Accessibility Check of the PDF. The report lists accessibility problems and provides information about fixing them. In most cases, you should fix the problems in the original source file. Acrobat Pro provides tools to fix accessibility problems but if the document will be revised and re-issued, the fixes should be in the source file.
- Rinse and repeat! Use your authoring tool to fix the source file, generate a new tagged PDF, and re-run the Full Accessibility Check in Acrobat Pro. For many documents that are well structured, you will only need one or two passes through these 5 steps to create accessible PDFs.
- Test with assistive technology such as a screen reader, screen magnifier and Acrobat's Read Out Loud feature.
Detailed information about the technology and techniques for making PDFs accessible is available from WCAG 2.0: PDF Techniques.
Microsoft Word to Accessible PDF Example
Let's take a quick look at using the techniques for creating a Word document for conversion to PDF. Suppose that your company publishes its list of training classes and schedule as a PDF document, and decides to include it on the website. You can use WCAG 2.0 PDF techniques to help ensure accessibility of the PDF as follows:
- Use the hierarchy of heading levels in Word, e.g., Heading 1 for the main title and Heading 2 for each class. See providing headings, example 2.
- Use Word table markup for the schedule information. In the Table Properties dialog, specify Repeat as header at the top of each page for the table header row. See using table elements for table markup, example 1. When this is done properly, you willonly need to set the scope of the header cells in Acrobat using the Table Editor.
- Provide accessible text alternatives within Word for all graphics and images. See applying text alternatives to images, example 2. Convert images that should not have alternative text to artifacts in Acrobat.
- Mark up links and link text within Word so they are accessible to assistive technology. See providing links and link text, example 1.
- Mark up lists (e.g., prerequisisites for the classes) using Word's list elements. See using List tags for lists, example 1.
- Specify the document language so that assistive technology will read the document correctly. This is best done in Acrobat, using the File > Properties dialog. See setting the default language, example 1.
- In Word, specify a meaningful document title to be displayed in the PDF window's title bar. By default, the file name is used, but this may not be meaningful or descriptive. Changing this default must be done in Acrobat, using the File > Properties dialog. See specifying the document title, example 1.
- Check that the order of the document's objects in the selection pane is correct (it goes from the bottom up), and verify the reading order of the content, structure, and tags in Acrobat. They should match the order in which the document is intended to be read. Also verify that tabbing follows the expected order. Certain formatting, images, and the PDF generation process can cause reading order issues. It should be checked in Acrobat. See ensuring correct tab and reading order .
- If necessary, use Acrobat tools such as the Touch Up Reading Order Tool and the Table Editor to repair accessibility issues. a well-structured source file will require few, if any, adjustments in Acrobat.
- As you do for web content, you should also make sure that text has sufficient size and contrast for accessibility.
Note that many of these techniques are implemented using the authoring tool, not Acrobat Pro. This means that future revisions of the document will already be structured for creating an accessible updated PDF.