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Whenever we publish online content, we need to make sure everyone can read it, including keyboard only users and people using assistive technology such as a screen readers.
This is also true for PDF documents. Similar to directly coding content into a website, there are special steps we must take to make sure that a PDF can be read by assistive technology.
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Make sure the PDF is in a text based format.
Create a logical reading order by providing a main heading and subheadings.
Tag and build your document structure in Microsoft Word
Apply properly nested headings <h1>, <h2>, <h3>, <h4>, <h5>, etc.
The <h1> heading should be reserved for the document title
Add paragraphs <p>Add ALT text (alternative text) for images.
Complex charts and diagrams that are embedded in the PDF can’t be accessed by screen reader users. In these cases a text based equivalent needs to be provided. This could be a summary of what the chart/graphic is conveying to sighted users.
Make sure there is sufficient color contrast between text and background.
Ensure that content displayed in a data table is fully accessible to screen reader users.
Provide a table of contents so it’s easy for users to find and navigate to information.
Save your Word or PDF document as a tagged PDF.
Provide meaningful document titles for screen reader users, using Adobe Acrobat Pro.
Avoid writing important information in the document header or footer. Screen readers will not announce content displayed in the header and footer.
Provide descriptive link text.
Ensure that any interactive elements are fully accessible.
Test your document in Microsoft Word or Adobe Acrobat for accessibility compliance.
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