When a PDF passes a PDF/UA check, that is good news and it is incomplete news. The check answers one question: do the rules a program can test hold? It does not answer whether a person using a screen reader gets a good document.
What the standard covers
PDF/UA-1 is ISO 14289-1, the technical standard for accessible PDF files. EN 301 549, which the European Accessibility Act points to, asks for accessible documents. PDF/UA supplies the file-level rules, and veraPDF is the open-source reference validator that tests a file against them.
What software can verify
- The document has a tag structure, with headings and lists marked as headings and lists.
- A document language is declared, and the file carries the PDF/UA identifier in its metadata.
- Fonts are embedded and have usable character maps, so text can be read aloud correctly.
- Tables mark their header cells, and links and form annotations are tagged.
- Page decoration is marked as an artifact, so a screen reader skips it.
- Every figure carries an alternative description. The check sees that a description exists.
What no program can verify
- Whether a picture description says what the picture is for. “Chart” passes the rule and helps nobody.
- Whether the reading order makes sense to a listener, even when every tag is valid.
- Whether the headings form a logical outline.
- Colour contrast, and information that is conveyed by colour alone.
How TagSmith-PDF splits the work
TagSmith-PDF does the mechanical part: tags, language, metadata, fonts, tables rebuilt from their grid, bookmarks from headings. Then it hands a person only what needs a person. A small vision model that runs on your PC drafts a description for every picture. Each draft stays marked AI DRAFT until someone accepts or edits it in Review, and unchecked drafts count as open items in the run.
Review also lists every figure and table that needs a look, and a screen-reader preview reads the document in reading order so you can hear what a listener would hear. The reports say “machine-verified” for that reason. They are evidence, not a certificate.
A ten-minute human pass
- Read each picture description. Fix any that name the picture without saying why it is there.
- Play the screen-reader preview once and listen for order that jumps around.
- Open two or three tables and check that the column headers are the real headers.
- Check contrast in the source document, because repair cannot change the design.
The release includes a short checklist for exactly this. Read a PASS as “the machine-checkable rules hold”, then spend the ten minutes on the rest. See real output from the demo set, or the full product page.