PDF/A restricts how PDF is used to support preservation over time. PDF/UA defines how PDF technology supports accessibility. The A in PDF/A does not mean the file is automatically accessible to assistive technology.
Some PDF/A conformance levels require structure. That still does not make them equivalent to PDF/UA. Specify the exact PDF/A part and level as well as the PDF/UA version.
PDF/A has several parts with different restrictions. Parts 1, 2 and 3 use conformance levels such as a and b; parts 2 and 3 also provide u. Broadly, b addresses visual reproduction, u adds Unicode character representation and a includes additional structural requirements. PDF/A-4 uses a different arrangement; do not mechanically attach the older level letters to it.
For a buyer, “archival PDF” is therefore not an unambiguous requirement. Ask the archive which part and, where relevant, level it needs. Then establish whether the publishing tools can produce that target alongside the separately specified accessibility target.
Text can look correct in a PDF/A file while its headings lack usable meaning for readers. Conversely, a well-structured PDF may need further work to meet preservation requirements. Neither assessment replaces the other.
A file can be correct before archiving and change during conversion, merging or optimisation. Test the file that will actually be handed over. A successful check of an earlier file does not establish the result for a later one.
Make the conversion chain explicit: source → PDF export → structural repair → archival conversion → final checks. If archival conversion removes structure, change the workflow or tool. Moving validation earlier, to a stage that happened to pass, does not solve the delivery problem.
Test a file containing the objects you actually use. Embedded attachments, digital signatures and other special features need to be included in the assessment. A successful text-page test does not establish that the same combination suits every report.
If the organisation delivers separate archival and reading files, give each a clear purpose. Confirm that both preserve the correct information and that readers are not offered an inaccessible archive copy as their only reading version.
Before
The web editor requests an accessible PDF. The archive requests PDF/A. Neither specifies exact versions.
After
The document owner establishes both targets and checks the final file against each.
Why this works The requirements can be assessed separately. A conversion satisfying one target must not hide a failure against the other.
Keep the output from both validation profiles and the manual accessibility review. If you deliver different files, name them clearly and bind each report to the correct file.
Sources
- PDF standardsPDF Association
- Conforming to both PDF/A and PDF/UAPDF Association
Examples are our own unless stated otherwise. These guides distinguish legal requirements, standards and practical advice. Passing an automated check is not a complete assessment of document accessibility.