508 Compliance Audit: PDF Document

Checklist 3 min
As with any form of communication produced by the DoD, PDFs must be 508-compliant. When preparing a PDF document, use this quality assurance check to comply with 508 requirements.

If you're using Adobe Acrobat Pro, use their automated accessibility check before finalizing your PDF. To do so, open the file with Adobe Acrobat Pro and enable the Accessibility feature under Tools > Protect & Standardize. Then run an Accessibility Check to verify these items below. For instructions, refer to Adobe Acrobat Support. Use this checklist to confirm manually that all PDFs are 508-compliant.

Document Properties

Setting the appropriate document properties, e.g., the document language, optimizes the output for screen readers and other assistive software. If using Adobe Acrobat Pro, you can access these properties within the window under File > Properties.

  • Name PDF with a descriptive filename
  • Provide the document with a meaningful title that identifies its purpose
  • Set document's Initial View to show Document Title
  • Turn Tagged PDF setting to Yes
  • Set Content Copying for Accessibility to Allowed
  • Set document's default reading language

Structured Tags

Screen readers use tags to interpret the document structure. Content that is repetitive or decorative should be changed to an artifact so screen readers can skip over it. If using Adobe Acrobat Pro, you can view a document’s tag structure by enabling it within View > Show/Hide > Navigation Panes > Tags. Refer to Adobe Support for instructions to edit structure within the Content and Tags panels.

  • Ensure all meaningful texts and objects correspond to a tag
  • Change content that is repetitive or decorative to an artifact
  • Structure the reading and navigation order of the tags to follow the same visual and logical order of the document
  • Duplicate vital information from a header, footer or watermark in the document as tagged content
  • Use appropriate type of tags for
    • Headings
    • Table of contents
    • Lists and sub-lists
    • Links

Images and Other Non-text Content

Screen readers cannot infer meaning from images and other objects, e.g., pictures, images of text, charts, diagrams, shapes, icons with hyperlinks, etc. To be compliant:

  • Add descriptive alternative text (alt text) that conveys the purpose and/or function for all figures, including images, embedded multimedia, etc.
  • Add descriptive captions to images/objects that convey the purpose and/or function of the objects
  • Provide mechanisms to stop, pause, mute or adjust the volume for audio from multimedia or animation that automatically plays for more than 3 seconds
  • Ensure multimedia has accurate and complete synchronized captions and audio descriptions
  • Exclude flashing objects from the document

Tables

Data tables in PDFs must be tagged appropriately. To be compliant:

  • Tag data tables with “Table” tag
  • Identify table headers properly, e.g., TH for simple tables and the headers attribute for complex tables
  • Associate data cells with their headings, e.g., the scope for simple tables or headers and IDs for complex tables
  • Use of RowSpan or ColSpan tags are appropriate for merged cells
  • Use data table captions and summaries where appropriate
  • Remove all table tags from Tag structure where tables are used for layout purposes and not data

Links and Controls

  • Use link names that describe the destination/purpose or the context
  • Give links unique names
  • Ensure the tab order matches the visual/logical order of the interactive elements

Forms

  • Include tooltips for form input elements that identify their purpose and match the associated text label
  • Group related form elements and elements with multiple labels appropriately, e.g., the group name is identified as part of the tooltip of the element; radio buttons have the same name
  • Ensure the tab order matches the visual/logical order of the form fields

Color and Sensory Characteristics

Color contrast is an integral part of accessibility, particularly for users with visual disabilities. Use a tool such as https://webaim.org/resources/contrastchecker/ to determine if contrast ratios are sufficient.

  • Do not use color as the sole method of conveying content or distinguishing visual elements
  • Do not use color as the sole method to distinguish links from surrounding text unless the luminance contrast between the link and the surrounding text is at least 3:1, and an additional differentiation (e.g., it becomes underlined) is provided when the link is hovered over or receives focus
  • Use patterns to convey the same information as color for non-text content, such as images
  • Use color contrast ratio between text and background that is at least 4.5:1

Miscellaneous

  • Use instructions that
    • Do not rely on shape, size, or visual location, e.g., "Click the square icon to continue" or "Instructions are in the right-hand column"
    • Do not rely on sound, e.g., "A beeping sound indicates you may continue"
  • Ensure the document is readable and functional when the text is set to reflow (Refer to Adobe Support: Reading PDFs with reflow and accessibility features for instructions)

References

U.S. Department of Health and Human Services. (n.d.). hhs-508-pdf-checklist.

Social Security Administration. (n.d.). AED COP PDF Test Check Sheet.