Making sure a PDF in accessible can be quite tricky. This guide will walk you through the necessary steps to having an accessible PDF.
Most PDFs are created from text-based processors such as Microsoft Word. It is much easier to create an accessible Word document and then convert it onto a PDF rather than editing in Adobe. If you do not have the original Microsoft Word document, you can convert the PDF into one to edit or you can proceed with editing the document as a PDF.
The recommended program to edit PDFs and make them accessible is Adobe Acrobat Pro DC which is free for anyone on our campus to download.
If you would like to learn how to make scans into accessible PDF documents, please visit our Creating High Quality Scans page.
Every PDF should be OCRed (optical character recognition). This means that all words in the PDF are recognized as text instead of an image. If you can highlight any text on a PDF then the characters are recognized. If not, just click on the OCR tool in Adobe Acrobat and Recognize Text for the whole document.
Acrobat has a built in Accessibility Checker that will point out any accessibility errors a document has. This must first be turned on and is not visible in the default settings of Adobe Acrobat.
Simply click “Accessibility Check” and a report will generate that looks like this:
From here, you can see if there are any accessibility issues present in the document
Once your document has been OCR scanned, the next step is to tag the document. Tagging your document will identify different areas of the document such as the difference between a heading, text, and image on the document's page.
Just right click on “Tagged PDF – Failed,” click fix, and Acrobat will automatically tag your document for you. Acrobat does not check the reading order, so that will have to be done manually. You can access the Reading Order from the Accessibility tool, and that will allow you to add Headings and adjust the reading order if necessary. Having a tagged PDF will allow anyone screen reader users to navigate through the document seamlessly. Untagged PDFs make it difficult for screen readers to recognize a document.
You can also tag your PDF by clicking the Accessibility tool and selecting "Autotag Document" as shown in the video below.
If your PDF originated in Word, it would be much easier to add headings in the Word document before converting to a PDF. If the PDF did not originate from Word, this video will show you how to add a heading in Adobe Acrobat DC.
Alternative text, or “alt text” describes the content of images, graphs and charts for Screen readers and Braille devices. The descriptions should be 1 or 2 meaningful sentences that best describe the image to someone who cannot see it. Alt text can be added to all images using the Accessibility tool.
Color contrast is another accessibility check that has to be done manually. Having insufficient color contrast in a PDF means that it contains text that may not be legible. This mainly includes have light colored text on a light-colored background or vice versa. Insufficient color contrast also applies to having a lot text that is green or red because color blindness is a common visual disability.
To edit the color of text with insufficient contrast, use the Edit tool, highlight the text, and change it’s color to something with better contrast.
For more on color contrast in documents visit Blackboard’s Text Contrast Page.