Accessibility and PDFs

PDF (Adobe Portable Document Format) is a popular file format used to distribute documents with their original printed appearance intact. This format tends to be rigid, and is difficult to use for readers on mobile devices or for people with visual or motor disabilities. Web pages or original document formats (e.g. Word) are often more accessible choices. The Australian government mandates that PDFs should never be used as the sole form of communicating information.

Accessible PDFs

PDFs can be relatively accessible if they are ‘tagged’ – if they contain information internally that identifies the structure (headings, lists, etc.), the reading order, table headings in data tables, and provides alternative text for images or other visual elements. Tagged PDFs are accessible to screen reading software for users with low or no vision, and allow enlargement and reflowing for people with print disabilities or mobile devices. To be accessible, a PDF must be tagged and contain alternative text for non-text elements including any graphics and form fields.

Tagged PDFs can be created automatically from well-structured Word documents. Untagged PDFs can be tagged through a fairly tedious manual process, using Adobe Acrobat Pro and other tools.

Classifying a PDF as image, text PDF, or tagged PDF

PDFs fall into three categories: images, text PDFs, or tagged PDFs.

An image PDF is just a picture of a page, either made on a scanner or through some automated process. To check whether a PDF is an image, open it in Adobe Reader and double – click on any text in the middle of a paragraph. If the entire page is selected, the page is an image. This is inaccessible to nearly everyone, and is the least versatile or desirable form of PDF.

A text PDF (without tags) contains the raw text of the document as well as its appearance. To check for text, open the PDF in Adobe Reader and double – click on any text in the middle of a paragraph. If only the word clicked on is selected, the PDF is a text PDF, but not necessarily tagged. Text PDFs can be read out loud and enlarged, but may not reflow properly or work well with screen reading software unless they are tagged.

A tagged PDF has text and other internal information (tags) that identify headers, lists, table headers, and other structure. Tags can only be seen in Adobe Acrobat Pro, but a PDF can be checked for tags in Adobe Reader. Open the PDF in Reader, then in the File menu, select Properties. In the lower part of the dialog box, it will say Tagged: Yes or Tagged: No. Tagged PDFs can be reflowed and enlarged. In Reader, select View Zoom Reflow (ctrl-4) and then increase the size of the text by steps up to 400% to see the impact of reflowing.


Testing PDFs for accessibility and making repairs

There are three alternatives for testing PDFs for accessibility, two of which provide repair tools.
The PDF Accessibility Checker (PAC 1.3) from www.access-for-all.ch is a free PDF testing program. Adobe Acrobat XI Pro includes accessibility checking and repair. It is available at no additional cost in the UI Adobe site license. CommonLook PDF from Netcentric Technologies is a plug-in for Acrobat Pro which makes it a more efficient document conversion tool to consider if remediating many PDFs. NetCentric also publishes plug-ins for Office to assist with creating accessible PDFs from Word and PowerPoint.

Alternatives to PDFs

Use native formats to replace or supplement PDFs. Word documents and PowerPoint slide decks in original format are more accessible for some users.

Present content through web pages rather than PDFs. Well-made web pages are considered to be the most accessible solution, and provide better web delivery than a posted PDF.

Replace PDF forms with web forms

Forms based on Word or PDF documents should be replaced by web forms if possible. PDF forms can be made accessible by manually adding tags for each form field, but the result is still a paper-based workflow. For now, consider using a Qualtrics survey to collect responses rather than a paper form. In the next year, a new Universal Workflow will be available which will be an even better alternative. It will combine accessible web forms for data intake with robust routing of form results to help keep track of data collected and actions taken.

Converting PDFs to Word

Acrobat XI Pro includes an option to convert PDF documents to Word. In the File menu, choose Save As Other, and choose Word Document. The results aren’t perfect, even when saving from a tagged document. However, the results might help tag a text PDF with no structure. In Word, structure could be applied and the new file could be converted to a tagged structured PDF as explained below.

Creating tagged, structured PDFs from Word 2010 and 2013

Users of Word 2010 or 2013 for Windows can choose Save As PDF in the File menu. In Word 2013, the File Export option includes improved choices for creating PDF bookmarks from headings in the Word document and preserving Word structure in the PDF. If the Word document used styles to create headings and other structure, those structural elements will be passed into the PDF. There is no comparable option in Word for Macintosh OS X.

Learn more about PDF accessibility

Adobe offers extensive web resources on accessibility and PDFs, starting at their Accessibility Resource Center, http://www.adobe.com/accessibility/. There are extensive accessibility training resources available http://www.adobe.com/accessibility/products/acrobat/training.html . The Adobe® Acrobat® XI Pro Accessibility Guide, at the URL
http://www.adobe.com/accessibility/products/acrobat/pdf/acrobat-xi-pro-accessibility-best-practice-guide.pdf
Also see the W3C PDF techniques for WCAG 2.0 at http://www.w3.org/TR/WCAG20-TECHS/pdf.html

SCIT 6/20/2013