PDF Accessibility Guide: Creating Inclusive Documents

Creating accessible PDFs ensures that your documents can be used by everyone, including people with disabilities. This comprehensive guide will walk you through the principles, techniques, and tools for making your PDFs truly inclusive.

Why PDF Accessibility Matters

Accessibility isn't just a nice-to-have feature—it's essential for:

• Legal compliance: Many countries have laws requiring digital accessibility (ADA in the US, Equality Act in the UK, etc.)
• Wider audience reach: Approximately 15% of the world's population lives with some form of disability
• Better user experience: Accessible documents are typically better organised and easier for everyone to use
• SEO benefits: Many accessibility features also improve search engine optimisation
• Social responsibility: Creating inclusive content demonstrates commitment to equality

PDF Accessibility Standards

Two main standards govern PDF accessibility:

WCAG 2.1 (Web Content Accessibility Guidelines)

While primarily designed for websites, WCAG principles apply to PDFs as well:

• Perceivable: Information must be presentable in ways all users can perceive
• Operable: Interface components must be navigable by all users
• Understandable: Information and operation must be understandable
• Robust: Content must be robust enough to work with various assistive technologies

PDF/UA (Universal Accessibility)

This standard specifically addresses PDF accessibility:

• Requires proper tagging structure
• Defines requirements for text, images, forms, and tables
• Ensures compatibility with assistive technologies
• Provides specific technical requirements for PDF creation

Essential Elements of an Accessible PDF

1. Document Structure

Proper structure is the foundation of PDF accessibility:

• Tagged PDF: All content must be properly tagged (headings, paragraphs, lists, etc.)
• Logical reading order: Content should flow in a logical sequence
• Bookmarks: Include bookmarks for documents longer than 9 pages
• Table of contents: For longer documents, include a linked table of contents
• Metadata: Include title, author, subject, and keywords in document properties

2. Text Accessibility

Text must be accessible to screen readers and other assistive technologies:

• Actual text: Use real text, not images of text
• Font properties: Use fonts that are clear and readable
• Colour contrast: Maintain a minimum 4.5:1 contrast ratio for normal text
• Language: Specify the document language and any language changes within the document
• No reliance on colour alone: Don't use colour as the only means of conveying information

3. Images and Non-Text Content

Visual elements need text alternatives:

• Alt text: Provide descriptive alternative text for all meaningful images
• Complex images: Include longer descriptions for charts, graphs, and complex images
• Decorative images: Mark purely decorative images as artifacts
• Text alternatives: Provide text alternatives for all non-text content

4. Tables

Tables require special attention:

• Table tags: Use proper table tags with headers identified
• Simple structure: Keep tables as simple as possible
• Header cells: Clearly identify header cells for rows and columns
• Avoid complex layouts: Don't use tables for layout purposes
• Captions: Include table captions and summaries when appropriate

5. Forms

Interactive forms need additional accessibility features:

• Field labels: Every form field needs a descriptive label
• Tab order: Ensure logical tab order through form fields
• Instructions: Provide clear instructions for completing the form
• Error handling: Include accessible error messages and validation
• Required fields: Clearly indicate which fields are required

Creating Accessible PDFs: Step-by-Step

Starting with Accessible Source Documents

Accessibility begins with your source document (Word, InDesign, etc.):

1. Use built-in heading styles for document structure
2. Add alt text to images in the source document
3. Use built-in tools to create tables (don't draw them)
4. Use list formatting for lists
5. Add document title, author, and other metadata
6. Use the accessibility checker in your authoring tool

Converting to PDF While Preserving Accessibility

When converting to PDF:

1. Use "Save as PDF" or "Export to PDF" rather than printing to PDF
2. Enable options for creating tagged PDFs
3. Check "Document structure tags for accessibility"
4. Include bookmarks for navigation
5. Verify that hyperlinks are preserved

Remediating Existing PDFs

For existing PDFs that need accessibility improvements:

1. Add tags if the document is untagged
2. Set the document language
3. Add alternative text to images
4. Check and fix reading order
5. Add bookmarks for navigation
6. Set document title and metadata
7. Run an accessibility check and address issues

Testing PDF Accessibility

Always test your PDFs for accessibility:

• Automated testing: Use built-in accessibility checkers
• Screen reader testing: Test with NVDA, JAWS, or VoiceOver
• Keyboard navigation: Ensure the document can be navigated without a mouse
• Colour contrast: Verify sufficient contrast with contrast checkers
• Manual review: Check reading order, alt text quality, and overall usability

Tools for Creating Accessible PDFs

Several tools can help you create and remediate accessible PDFs:

• Adobe Acrobat Pro: Comprehensive tools for creating and fixing accessible PDFs
• Microsoft Word: Built-in accessibility checker and PDF export with accessibility options
• Adobe InDesign: Advanced features for creating accessible PDFs from design documents
• PAC (PDF Accessibility Checker): Free tool for checking PDF/UA compliance
• RevisePDF: Tools for optimising PDFs while maintaining accessibility

Conclusion

Creating accessible PDFs requires attention to detail and an understanding of how people with disabilities use documents. By following the guidelines in this article, you can ensure your PDFs are usable by everyone, comply with legal requirements, and provide a better experience for all users.

Remember that accessibility is not just about compliance—it's about inclusion. By making your PDFs accessible, you're ensuring that all users, regardless of ability, can access and use your information.

Start implementing these practices today to create more inclusive documents that truly work for everyone.