Create an Accessible PDF

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It is important that PDFs being used for instruction feature Optical Character Recognition (OCR) so individuals with different learning abilities can access them.

At Evergreen, we distribute a lot of instructional material in the form of PDFs (Portable Document Format).

  • When selecting or creating PDFs for use as course materials, make sure the document features OCR.
  • Optical Character Recognition is "the mechanical or electronic conversion of scanned images of handwritten, typewritten or printed text into machine-encoded text."
  • OCR is a simple preset that must be selected within Acrobat Pro before starting your scans. Read about OCR and recommended scanning presets below.

Using PDFs from Other Sources

There may not be a lot you can do if you are using a PDF from another source (such as journal articles or scanned photocopies) but there are a few elements you should look for when selecting PDFs to assign.

  • Clear, readable text. Text may be inaccessible if it is warped, in an unusual font (such as Curlz or Handwriting), or is covered by handwriting/drawing. Students may be using software that uses OCR (Optical Character Recognition) in order to convert text to audio, if the characters aren't clear, the audio will be convoluted.
  • Large font. Some individuals can read large type if there is a high contrast (e.g. black font against a white background or vice versa).
  • Page numbers. Page numbers, particularly located at the top of pages, help students navigate where they are in the text.
  • Straightforward structure. Many screen readers scan text from left to right, top to bottom. PDFs which include minimal break-out text boxes, tables, wrap-around text, etc., are generally accessible to students.
  • Few images and alternative content. It goes without saying that students with visual impairments may not be able to access an image but this applies to other content as well: graphs, tables, diagrams, etc. Captions and descriptions for visual-based content can provide students with information they might have missed otherwise.

How to Make Accessible PDF Docs

Please note: This process assumes that you are using Adobe Acrobat Pro, version 9 or higher, on either a Windows or Macintosh computer.

Scanning Process

  • Turn on scanner
  • Place first page on scanner bed, aligned according to size and scanner layout
  • Start Adobe Acrobat Pro from the Start Menu or Launcher
  • Navigate to File > Create PDF From Scanner. Select "Configure Presets."
    • On a Mac you are automatically prompted with the presets option screen below.


  • Ensure that Optical Character Recognition is selected.
    • DPI must be 300 or higher to ensure the character recognition process is successful.


  • If you select the "options" button next to the OCR checkbox, you are able to change the OCR type from "ImageScan" to "ClearScan."
    • ClearScan OCR will keep the file size low while maintaining quality.
    • Adobe has an excellent writeup about these options.

Converting an existing PDF

  • Open the PDF in Acrobat Pro
  • Select "Recognize Text In This File" from the right hand side bar
  • Click "Edit" on the pop up window to ensure you have the following settings
  • English US - ClearScan - 300DPI
  • Click OK

Need help? Contact the Academic Computing Help Desk at 360-867-6231 or create a help desk support ticket.