PDF Editing and Accessibility
PDFs (Portable Document Format), with their platform-neutral openability and read-only format, have become one of our most useful tools for saving and sharing documents, and are a common feature in online as well as face-to-face courses (read this article for more on the interesting history of PDFs). However, they can present challenges for some users, especially for those who are sight-impaired or for those wishing to modify files for accessibility purposes. As schools move toward the goal of universal accessibility of the learning environment and educational content, it is important to stay abreast of emerging technologies designed to meet their needs. Recent advances have greatly improved the accessibility and functionality of PDFs, helping them maintain their utility and value for current educational use.
The very thing that makes PDFs so useful is also what makes them challenging for accessibility and editing: they preserve the exact type and appearance of the original document created by the author in an image-like file that is not intended to be editable. Students with visual impairments often use screen readers such as JAWS, NVDA, or Apple’s built-in tool, VoiceOver, to convert online text to audio. However, PDFs do not always contain the information that allows screen readers to recognize the text and other content within the document— to screen-readers, PDFs can sometimes be completely unreadable, or in other cases include a jumble of necessary and unnecessary information, depending on how the file was generated.
To create an accessible PDF, you need to ensure that the source document is accessible, by providing alternative text for images, hyperlinks and other visual elements and by adding “accessibility tags” that accurately describe the content and logical order of the document, including headers, lists, tables, etc. In Microsoft Office applications, use the embedded “Accessibility Checker” tool to identify and correct any problem areas before saving and sharing the PDF. Some of the bigger points are:
- Headings: in Word, use the “style pane” to choose header styles that will add accessibility code for the various font styles and formats
- Images: right-click on the image to add alternative text descriptions
- Presentation structure: all images or other visuals should be aligned “inline”, i.e. the anchor point must be spatially on the left side of the page, even if the location of the image appears elsewhere on the page
- Tables: all columns must have headers; if the table is too complicated, use a spreadsheet or put it on a web page
For more information, here is a detailed guide to making accessible PDF’s for documents created with Microsoft Word, Excel, PowerPoint, etc.
If you do not have access to the original source document, eg. if the document was created by an image-based scanner, OCR (Online Character Recognition) software such as the free Online OCR enables you to convert the file to an editable Word, Excel or plain text document. You are then free to edit the document, add tags as directed above, and resave as an accessible PDF.
While there are numerous other useful accessibility tools available for many different purposes and media devices, Adobe Acrobat Pro (discounted with an ACTEM membership) is worth mentioning for its powerful editing and accessibility features. While tagging documents manually within the authoring software is considered the most effective strategy, Acrobat Pro’s accessibility checker and automated tagging features can save time and are especially helpful when working with complex files.
Finally, if you wish to scan a document to PDF, make sure to save it as a PDF text rather than image file, a feature common in older printer-scanners. Better yet, use Adobe Acrobat Pro or a modern printer’s embedded OCR technology to create an editable text document. In addition, many smartphones can be used to scan and convert documents to PDF and/or OCR editable images, using free apps like GoogleDrive, Adobe Scan, CamScanner, and FineScanner and Evernote’s Scannable.