PDF/UA-1 vs PDF/UA-2: Which Standard Should Your Accessible PDF Project Target?

PDF/UA-1 vs PDF/UA-2: Which Standard Should Your Accessible PDF Project Target?

A procurement brief arrives with a simple instruction:

“Make these PDFs PDF/UA compliant.”

That instruction is no longer quite specific enough.

There are now two major generations of PDF/UA to understand:

PDF/UA-1 and PDF/UA-2.

PDF/UA-2 was published as ISO 14289-2:2024 and defines accessibility requirements for tagged PDFs based on PDF 2.0. PDF/UA-1 remains relevant for PDF 1.7 workflows rather than simply disappearing when PDF/UA-2 arrived.

For organizations planning remediation, the practical question is therefore not:

“Which standard is newer?”

It is:

“Which PDF format, accessibility requirements, user environments and procurement obligations does this project actually need to support?”

Quick Answer

PDF/UA-1 is the established accessibility standard for PDF 1.7 documents.

PDF/UA-2 is the newer standard for PDF 2.0 documents and introduces a more modern tagged-PDF model.

PDF/UA-2 does not mean every existing PDF/UA-1 document suddenly needs to be converted.

For a remediation project, first establish:

Source PDF → Required PDF version → Contract/legal requirements → Accessibility target → Validation → Human QA

The PDF Association specifically notes that PDF/UA defines the technical characteristics required of an accessible PDF; it does not prescribe the remediation process itself.

What Is PDF/UA?

PDF/UA stands for PDF/Universal Accessibility.

It defines requirements for making PDF content usable with assistive technologies.

A properly structured accessible PDF may need to communicate information such as:

• Headings
• Paragraphs
• Lists
• Tables
• Figures
• Alternative descriptions
• Reading sequence
• Links
• Form controls
• Language
• Document structure

The important distinction is:

A PDF can look perfectly correct visually while its underlying structure is unusable to a screen-reader user.

PDF accessibility therefore involves much more than visual design.

What Is PDF/UA-1?

PDF/UA-1 is the first generation of the ISO PDF accessibility standard.

It was designed around the PDF 1.7 specification.

It has become widely established in document accessibility workflows and remains relevant for large existing collections of PDFs.

A typical PDF/UA-1 remediation workflow can include:

• Building or correcting the tag tree
• Establishing logical reading order
• Marking headings semantically
• Structuring lists
• Correcting tables
• Adding alternative text
• Artifacting decorative content
• Correcting document language
• Labelling links and form fields
• Adding bookmarks where appropriate
• Correcting metadata
• Validation and manual QA

The output should not merely look unchanged.

Its underlying structure should communicate the document meaning to assistive technology.

What Is PDF/UA-2?

PDF/UA-2 is ISO 14289-2:2024.

The PDF Association describes it as defining the use of tagged PDF in documents conforming to ISO 32000-2:2020 — PDF 2.0 to ensure accessible content.

That distinction matters.

PDF/UA-2 is not simply:

“PDF/UA-1 with a higher version number.”

It is built on the newer PDF 2.0 architecture.

Current technical guidance identifies changes involving areas such as:

• PDF 2.0 structure
• Structure element attributes
• Annotations
• Math/MathML
• Associated files
• Links and structural destinations

PDF/UA-1 vs PDF/UA-2

The procurement lesson

Do not write:

“PDF/UA compliant.”

when your project actually requires a particular target.

Specify the expected standard and version.

Does PDF/UA-2 Replace PDF/UA-1?

Not in the simple sense that every older accessible PDF must immediately be upgraded.

PDF/UA-1 and PDF/UA-2 correspond to different generations of PDF.

Current technical guidance notes that PDF/UA-1 remains applicable to PDF 1.7, while PDF/UA-2 targets PDF 2.0.

That means an organization with 50,000 existing PDF 1.7 documents should not assume that the appearance of PDF/UA-2 creates an automatic requirement to migrate every file to PDF 2.0.

The appropriate decision depends on:

• Required delivery format
• Customer specifications
• Procurement requirements
• Regulatory context
• Distribution systems
• Assistive-technology compatibility
• Authoring and validation tooling

PDF/UA and WCAG Are Not the Same Thing

This distinction is critical.

PDF/UA focuses specifically on accessible PDF technology.

WCAG provides broader accessibility requirements for digital content.

PDF/UA does not cover every accessibility consideration.

For example, the PDF Association notes areas outside PDF/UA's scope including colour/contrast and some content-related accessibility issues.

So:

PDF/UA validation ≠ complete WCAG evaluation.

A robust accessible-PDF workflow may need both technical PDF/UA validation and WCAG-oriented human review.

Why Automated Validation Is Not Enough

Suppose a validator confirms that an image has alternative text.

That does not establish whether the alternative is useful.

For example:

Alt text: “Graph”

Technically, alternative text exists.

But the reader may need to know:

• What variables are plotted
• The main trend
• A significant comparison
• An important peak or decline

Likewise, software can inspect a table's structure.

A human may still need to determine whether the relationships make sense when navigated non-visually.

PDF/UA Validation vs Human QA

The strongest workflow is:

Automated Validation + Expert Review + Assistive-Technology Testing

What Should Be Included in PDF Accessibility Remediation?

A professional scope should normally consider:

Document structure

• Correct tag hierarchy
• Headings
• Paragraphs
• Lists
• Figures
• Captions

Reading order

The sequence exposed to assistive technology must represent the intended reading experience.

Multi-column pages, sidebars, footnotes and positioned content require particular attention.

Tables

Check:

• Header cells
• Header relationships
• Scope
• Spanning cells
• Complex structures

Images

Meaningful images need appropriate alternatives.

Decorative material should not create unnecessary screen-reader noise.

Links

Users need meaningful link information and correct tagging.

Forms

Where forms exist, review:

• Labels
• Names
• Roles
• States
• Keyboard interaction
• Tab sequence

Language and metadata

Correct document-language information helps assistive technologies choose appropriate pronunciation.

A Better Buyer Checklist

Before awarding a large remediation project, ask the supplier:

• Which PDF/UA version are you targeting?
• Which PDF version will be delivered?
• How do you evaluate WCAG requirements outside PDF/UA?
• Which validator is used?
• Are machine results manually reviewed?
• How are complex tables handled?
• Who reviews image descriptions?
• Is reading order manually checked?
• Is assistive-technology testing included?
• Which screen readers are tested?
• What evidence accompanies delivery?
• How are failed files corrected and retested?
• How are exceptions documented?

A vendor should be able to explain why a file is accessible, not merely send a green validation report.

Choosing a Target for a Large PDF Backlog

For a large collection, begin with representative sampling.

Select examples containing:

• Simple text
• Multi-column pages
• Tables
• Charts
• Scanned content
• Forms
• Footnotes
• Mathematical content
• Complex layouts

Then determine:

Inventory → Complexity → Required Standard → Sample Remediation → Validation → Human QA → Production

This prevents a procurement team from discovering halfway through 20,000 documents that the original scope did not account for complex content.

How Gentize Supports PDF Accessibility Projects

Gentize currently lists PDF/UA remediation, WCAG 2.2 AA auditing/remediation, screen-reader testing using NVDA, JAWS and VoiceOver, alt-text and structural tagging, and accessibility documentation among its accessibility capabilities.

Gentize also publicly documents a 12,000-document accessibility remediation programme involving bulk PDF and EPUB remediation and assistive-technology testing.

For teams evaluating a large PDF backlog, Gentize offers a 10-file accessibility check, which can be useful for sampling representative document types before full scoping.

Internal verification required: Gentize's public pages currently say PDF/UA but do not clearly state that production is formally offered specifically to PDF/UA-2 / ISO 14289-2:2024. Do not claim “Gentize provides PDF/UA-2 remediation” in the published article until the accessibility team confirms this internally.

Final Takeaway

PDF/UA-2 is an important development in document accessibility, but “newer” does not automatically mean “convert every PDF.”

PDF/UA-1 and PDF/UA-2 belong to different PDF generations.

For buyers, the better question is:

What format and accessibility outcome does this document collection actually require?

Then define:

PDF version → PDF/UA target → WCAG evaluation → validation → human QA → assistive-technology testing

That creates a defensible remediation workflow instead of a version-number exercise.