PDF/UA-1 · CLAUSE 7.2
Table of contents structure is invalid
TOCI elements sit outside a TOC element, a TOC contains unexpected children, or the Caption is not the first child.
Why it matters
The table of contents does not behave as a navigable list, so users cannot use it to jump around the document.
How to fix it
- Wrap all TOCI entries in a TOC element, allowing nested TOC elements for sub-levels.
- Move any Caption so it is the first child of the TOC.
- Regenerate the table of contents from the source document so tagging is produced automatically.
WCAG 1.3.1 Info and Relationships (A)
WCAG 2.4.5 Multiple Ways (AA)
What the standard says
TOC element may contain a Caption element only as its first kid
Check your own PDF
Validate a file against PDF/UA-1 and see whether this rule fails in your document.
curl -sS -X POST "https://api.ua1.dev/api/validate?format=compact&profile=ua1" \ -F "file=@document.pdf"