Reading Order

The reading order determines how screen readers navigate the document.

Correct reading order:

• Flows logically (like reading a book)
• Columns read in proper sequence
• Headers precede content
• Captions near images
• Page numbers at consistent points

• Random jumping between elements
• Text boxes read out of context
• Footnotes read in wrong place
• Multi-column confusion

Alternative Text

All non-text content needs descriptions:

Images:

Good: "Bar chart showing sales increase from $1M in 2023 to $1.5M in 2024"
Bad: "chart" or "image123.jpg"

Complex Graphics:

• Provide detailed description
• Or link to longer description
• Consider data table alternative

• Mark as artifact (not read)
• Background images excluded
• Design elements hidden

Table Accessibility

Tables need proper structure for screen readers:

Required elements:

• Header rows/columns identified
• Scope defined (row/column/both)
• Summary for complex tables
• Avoid merged cells when possible

<Table>
  <TR>
    <TH scope="col">Quarter</TH>
    <TH scope="col">Sales</TH>
    <TH scope="col">Profit</TH>
  </TR>
  <TR>
    <TD>Q1</TD>
    <TD>$100K</TD>
    <TD>$20K</TD>
  </TR>
</Table>

Color and Contrast

Contrast Requirements:

• Don't use color alone to convey information
• Provide text or patterns as alternatives
• Test with color blindness simulators
• Ensure links are distinguishable

Form Accessibility

Interactive forms need:

Labels:

• Every field has a label
• Labels are properly associated
• Required fields indicated
• Instructions clear

• Logical field sequence
• Skip navigation options
• Focus indicators visible
• Error handling accessible

• Proper input types used
• Date formats explained
• Help text available
• Validation messages accessible

Creating Accessible PDFs

From Microsoft Word

Before converting:

• Use heading styles

• Add alt text to images

• Use proper lists

• Create accessible tables

• Run accessibility checker

Converting to PDF:

• File > Export > Create PDF/XPS
• Options > Document structure tags
• Options > ISO 19005-1 (PDF/A)

From Adobe InDesign

Design phase:

• Use paragraph styles
• Set export tags
• Define reading order
• Add alt text to images
• Create bookmarks

• Export to Interactive PDF
• Create Tagged PDF checked
• Set language
• Include bookmarks

From Scanned Documents

OCR Processing:

• Scan at 300 DPI minimum
• Run OCR (Optical Character Recognition)
• Verify text accuracy
• Add tags manually
• Set reading order

• OCR isn't 100% accurate
• Complex layouts challenging
• May need manual cleanup
• Consider accessible alternative

Testing PDF Accessibility

Automated Testing

Adobe Acrobat:

• Tools > Accessibility > Full Check
• Review issues by category
• Use Make Accessible wizard
• Fix flagged problems

• Tagged PDF check
• Document language
• Color contrast
• Reading order
• Alt text presence
• Table structure

Manual Testing

Screen reader testing:

• Test with NVDA (free)
• Test with JAWS
• Test with VoiceOver
• Listen to reading experience

• Tab through document
• Access all links
• Navigate forms
• Use bookmarks

• Zoom to 200%
• High contrast mode
• Reflow testing
• Color blindness check

Testing Checklist

Structure:

• [ ] Document has tags
• [ ] Heading hierarchy correct
• [ ] Reading order logical
• [ ] Language specified

• [ ] All images have alt text
• [ ] Tables have headers
• [ ] Links have meaningful text
• [ ] Lists properly structured

• [ ] Contrast meets requirements
• [ ] Text resizable
• [ ] Color not only indicator
• [ ] No flashing content

• [ ] Fields labeled
• [ ] Tab order correct
• [ ] Instructions clear
• [ ] Errors identifiable

Remediation Techniques

Adding Tags to Untagged PDFs

Using Acrobat:

• Open PDF
• Tools > Accessibility > Add Tags to Document
• Review and correct auto-tagging
• Manually fix complex areas
• Set reading order

Fixing Reading Order

• Tools > Accessibility > Reading Order
• Select content areas
• Assign proper tags
• Arrange order in panel
• Test with screen reader

Adding Alt Text

• Edit tag tree
• Select image tag
• Add alternative text
• Or mark as artifact (decorative)
• Verify screen reader reads it

Remediating Tables

• Identify table in tag tree
• Use Table Editor
• Define header cells
• Set scope (row/column)
• Add summary if complex

Common Accessibility Issues

Issue 1: Missing Tags

Problem: PDF has no semantic structure Solution: Add tags to document or re-export from source

Issue 2: Missing Alt Text

Problem: Images not described Solution: Add alt text to each image or mark decorative

Issue 3: Incorrect Reading Order

Problem: Content reads in wrong sequence Solution: Adjust reading order in touch-up order panel

Issue 4: Color Contrast

Problem: Text hard to read Solution: Increase contrast ratio, use darker colors

Issue 5: Scanned Text

Problem: Text is actually an image Solution: Run OCR, verify accuracy, add tags

Issue 6: Complex Tables

Problem: Tables don't read correctly Solution: Define headers, simplify structure, add summary

Accessibility by Document Type

Reports and Documents

Key considerations:

• Clear heading structure
• Alt text for all graphics
• Table accessibility
• Proper list formatting
• Reading order verified

Forms

Key considerations:

• Field labels associated
• Tab order logical
• Instructions clear
• Error messages accessible
• Submit button labeled

Presentations

Key considerations:

• Slide titles unique
• Alt text for images
• Charts described
• Reading order per slide
• Simple layouts

Financial Documents

Key considerations:

• Table headers defined
• Data relationships clear
• Charts have descriptions
• Reading order for columns
• Accessibility before conversion

Tools and Resources

Testing Tools

Learning Resources

Standards:

• WCAG 2.1: w3.org/WAI/WCAG21
• PDF/UA: pdfa.org/pdf-ua-iso-14289
• Section 508: section508.gov

• WebAIM articles
• Adobe accessibility resources
• Deque University courses

Conclusion

Creating accessible PDFs is both a legal requirement and an ethical imperative. By following accessibility standards and best practices, you ensure everyone can access your content.

Accessibility Checklist Summary

Document Structure:

• [ ] Tagged PDF
• [ ] Proper heading hierarchy
• [ ] Logical reading order
• [ ] Language specified

• [ ] All images have alt text
• [ ] Color contrast adequate
• [ ] Color not only indicator
• [ ] Text scalable

• [ ] Headers identified
• [ ] Scope defined
• [ ] Structure simple
• [ ] Summary if complex

• [ ] Fields labeled
• [ ] Tab order logical
• [ ] Instructions clear
• [ ] Accessible error handling

Key Takeaways

• Plan for accessibility: Design with accessibility in mind from the start
• Use proper structure: Tags and reading order are essential
• Describe visual content: Alt text enables understanding for all
• Test thoroughly: Use both automated and manual testing
• Remediate existing PDFs: Fix accessibility issues in legacy documents

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