Standards

PDF/UA

Also: ISO 14289, PDF/UA-1, PDF Universal Accessibility

ISO 14289 — the international standard for accessible PDF documents. Cited by EAA, Section 508, and EN 301 549 chapter 10 as the conformance target for PDF accessibility.

PDF/UA — short for “PDF/Universal Accessibility” — is the ISO standard (ISO 14289-1, with PDF/UA-2 in development) that defines what makes a PDF file accessible. It is the PDF-side counterpart to WCAG: both describe how content has to be structured for assistive technology to read it, just for different document formats.

What PDF/UA requires

The standard sets specific requirements on the PDF file’s internal structure:

  • Tagged content. Every meaningful element — paragraphs, headings, lists, tables, figures — must be wrapped in a structure tag (<P>, <H1>, <L>, <Table>, <Figure>) so screen readers can announce it correctly.
  • A logical reading order. The structure tree’s tag order must match the order a sighted reader follows, not the visual coordinate order the PDF was laid out in.
  • Alternative text for figures and images, via /Alt entries.
  • Language declared at the document level and on any inline text in a different language.
  • Tables with header cells identified by <TH> tags, plus Scope attributes for complex tables.
  • Form fields with accessible names and roles set via PDF’s MK and TU dictionaries.
  • Decorative content marked as artifact so screen readers skip it (the PDF equivalent of alt="").

The full standard is ~30 dense pages; the operative summary is: every piece of content in the PDF must have a structural role that an assistive technology can interpret.

How it relates to WCAG

WCAG explicitly applies to PDFs (W3C’s “WCAG 2.1 Techniques for PDF” documents this), but PDF/UA exists because WCAG’s web-first language doesn’t map cleanly to every PDF feature. PDF/UA is the format-specific specification; WCAG is the cross-format accessibility goal. A PDF/UA-1 conformant document satisfies WCAG 2.x AA for the parts of WCAG that apply to PDFs.

How to test conformance

The reference free checker is PAC (PDF Accessibility Checker) from Switzerland’s “Access for All” foundation. PAC tests against PDF/UA’s machine-checkable requirements (which catch maybe 60% of issues); the remainder — meaningful alt text, correct reading order on complex layouts, table-header semantics — still requires manual review.

Adobe Acrobat Pro’s “Accessibility Check” also runs an internal PDF/UA-aware scan, but is widely considered weaker than PAC.

Why this matters

In jurisdictions where the EAA, Section 508, or EN 301 549 apply, the PDFs you publish are subject to accessibility requirements just like your web pages. Sample affected documents: annual reports, downloadable forms, regulatory filings, e-books distributed as PDF, contracts.