Correct Tab and Reading Order [WCAG.PDF.03]
Test Basis (WCAG 2.0)
This test is based on the WCAG 2.0 Technique PDF3: Ensuring correct tab and reading order in PDF documents
Technique URL (WCAG 2.0)
Why this maybe a Barrier
For sighted users, the logical order of PDF content is also the visual order on the screen. For keyboard and assistive technology users, the tab order through content, including interactive elements (form fields and links), determines the order in which these users can navigate the content.The tab order must reflect the logical order of the document.
Logical structure is created when a document is saved as tagged PDF. The reading order of a PDF document is the tag order of document elements, including interactive elements.
If the reading order is not correct, keyboard and assistive technology users may not be able to understand the content.
WCAG 2.0 Reference
1.3.2 Meaningful Sequence: “When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined. (Level A)”
2.1.3 Keyboard (No Exception): “All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes. (Level AAA)”
2.4.3 Focus Order: “If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components receive focus in an order that preserves meaning and operability. (Level A)”
WCAG 2.0 Success Criteria 1.3.2