Creating Accessible PDF Documents

Description

This article provides instructions on how to create PDF files that meet accessibility standards at Idaho State University (ISU).

Guide Navigation

Understanding the Structure of a PDF 

Think of a PDF as having three important layers that provide different types of information to users.

  • Visual: What is seen on the screen. A primary benefit of a PDF is that it maintains the layout and appearance of the original document (also know as the "source document" used to create the PDF. It looks the same when it is displayed--even across different devices, screen sizes, and when printed.
  • Content: Contains basic formatting applied to content such as text, colors, lists, tables, images, and heading structure. 
  • Tags: Contains the document's structure, including headings, links, lists, and tables. This information supports assistive technology such as screen reading software which provides users access to the tags structure in this layer. 
    • An "accessible" PDF file is usually referring to "tagged" PDF files. Tags are a set of standard structure types and attributes that allow page content (text, graphics, and images) to be extracted and reused for other purposes. One of those purposes is to present information to screen reader technology users. Tags have no impact on the visual layout of a PDF. 
    • Tags allow users of assistive technology to quickly navigate to elements of the document that are identified as headings in this layer.

If you are only looking at a PDF from the visual perspective, you may not notice that it is missing a title element. The file will open normally and look fine on your screen. Unless you specifically check the document properties, you may not realize that your document is not accessible. 

Providing a PDF Title Element

The Title Element is a critical piece of metadata that gives context and clarity to a document. For screen readers users, the title is often the first piece of information announced, helping them understand what the file contains. Without a title, users may hear only the generic file name, which often does not describe what the document actually contains.

For example, the file name might be "CIVICA NEJM June 2022" which does not provide any information about what the document contains. Adding a title such as, "Peer reviewed article on a radical treatment for insulin pricing (2022)" tells the screen reader users what the document is about before they open it.

Tip: How to Fix It

  • Add a title to the original document that was used to create the PDF. In Microsoft Word, select File in the top left corner of the document. select Info on the left menu, and on the right side under Properties, look for Title. Select Add a title and paste or type your test, then click away and save the file.
  • Use the UDOIT Accessibility Assistant

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Providing File Tags for Navigation

Tags identify the logical reading order of the content, distinguish headings and subheadings, mark lists and tables, and connect images with their alternative text. They act like a roadmap, allowing screen reader users to navigate a file efficiently. When a document is untagged, it leads to a confusing reading experience where headings are indistinguishable from body text, tables are read in the wrong order, lists lose their meaning, and the content of informational images is not conveyed.

This problem becomes especially severe in documents that use multiple columns. While a sighted reader can visually follow the flow of text across multiple columns, a screen reader parsing a PDF without tags will often read straight across the page from left to right, jumbling the end of one column with the beginning of the next. What makes sense visually turns into nonsense when read aloud. 

Tip: How to fix it

  • Fix in Canvas: This issue cannot be fixed directly in Canvas. Instead, download the file and use a third-party tool,s uch as Adobe Acrobat Pro to add tags to the document. Then, replace the original file with the updated file.
  • Fix in UDOIT: In the “Review Course Files” area of UDOIT, locate the file that lacks tags and select it. On the right-hand side of the modal, find the “Alternate Formats” menu and request “Canvas Page (includes HTML file)” or "Auto Tagged PDF." Then, choose either “Replace file with a page” or "Replace file Auto Tagged PDF" so that students can interact with the accessible version instead of the original untagged PDF.

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Avoiding Image-Based Files

When a PDF is created by scanning a paper document, the scan is saved as an image of the page rather than real, selectable text. While it looks like a normal PDF on the screen, it’s essentially just a picture. For students who use screen readers or other assistive technologies, that picture has no readable text: it’s blank. A student who relies on assistive technology will not be able to access any of the words in the file.

Even for students who can see the text, scanned PDFs take away the flexibility of a true digital document. The words cannot be searched, and highlighting or annotation tools don’t work properly because the software has no text to interact with. Students who need to resize text for readability are stuck zooming in on a blurry image. For multilingual students, translation tools also fail, since there is no text to translate.

Scanned PDFs can also be much larger in file size, which can cause long loading times and storage issues. The text may appear crooked, faded, or distorted depending on the quality of the scan, adding another layer of difficulty. These barriers can be frustrating for any student, but for those who rely on assistive technology, a scanned PDF can make course materials completely unusable.

Tip: How to fix it

  • Fix in UDOIT: In the “Review Course Files” area of UDOIT, select the image-based PDF. On the right-hand side of the modal, find the Alternate Formats menu and choose Canvas Page (includes HTML file). Select Request to generate a Canvas page version of the file. Once the page is created, open it and review the content to make sure all the text is legible and properly formatted. Use the RCE and/or the DesignPLUS sidebar to structure the content with clear headings, add alternative text to images, and enhance readability with design elements that support engagement. Finally, once you’ve confirmed the page is accessible, return to the UDOIT “Review Course Files” interface. Select the file and choose Replace file with a page. This step ensures that students will now interact with an accessible Canvas page instead of the original scanned PDF.

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Converting a Document to PDF

Microsoft Office documents keep accessibility information intact when properly converted to PDF. For example, a document created in Word with accessibility in mind should contain almost all the information necessary to an accessible PDF.

There are two methods of converting a document to PDF:

  1. With the document open, select File > Save As. Open the file type menu and select the PDF (*.pdf) file type, and select Save. By default the Document structure tags for accessibility should be checked in the Options button. 
  2. With the document open, select File > Export. Select the Create PDF/XPS button. Identify the location for the file download and select Publish.

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