Resources

Authoritative standards

PDF Accessibility Standards Library

A curated library of the core PDF accessibility standards and guidance documents: WCAG, PDF/UA, Section 508, ADA Title II, WTPDF and Matterhorn.

9 min readUpdated 2026-07-09

For teams that want the actual standards and authoritative source documents behind PDF remediation.

Use official standards documents as the source of truth.

Link to copyrighted ISO standards rather than copying their text.

Use open-licensed or public-domain material only with correct attribution and caveats.

How to use this library

This page collects the standards and technical references that matter most for PDF accessibility. It is designed as a practical starting point for document owners, accessibility leads, procurement teams and developers.

The library deliberately separates "safe to link and summarize" from "safe to reproduce." Many standards are authoritative but not open for full republication.

The relationship between the standards

WCAG defines digital accessibility outcomes. PDF/UA defines PDF-specific implementation requirements. Section 508 and ADA Title II create legal or policy obligations that reference accessibility standards. Matterhorn and WTPDF help practitioners understand how tagged PDF should behave.

Permissively reusable material

The strongest reusable candidate is the PDF Association Well-Tagged PDF specification, which is licensed under Creative Commons Attribution 4.0. W3C materials can often be copied and distributed under W3C licence terms, but derivative publication of technical specifications is restricted. Section508.gov says most material is public domain in the U.S., while warning that some photos or third-party materials may be restricted.

Standards and source documents

WCAG 2.2 Recommendation

W3C

Current W3C recommendation for web accessibility. Useful because W3C advises current WCAG versions for future applicability, while WCAG 2.1 remains referenced by many regulations.

Reuse note: Link and summarize. Copy/distribute only under W3C document licence conditions.

WCAG 2.1 Recommendation

W3C

The standard referenced by ADA Title II web and mobile app accessibility requirements.

Reuse note: Link and summarize. Copy/distribute only under W3C document licence conditions.

How to Meet WCAG Quick Reference

W3C WAI

Practical filterable reference for success criteria and techniques, including PDF techniques.

Reuse note: Link and summarize. Useful as a reference rather than republishing in full.

PDF/UA-1: ISO 14289-1

PDF Association / ISO

File-format-specific accessibility standard for PDF/UA-1.

Reuse note: Do not reproduce the ISO standard text. Link to the official no-cost download or ISO purchase source.

PDF/UA-2: ISO 14289-2

PDF Association / ISO

PDF/UA standard for PDF 2.0 files, aligned with Well-Tagged PDF accessibility conformance concepts.

Reuse note: Do not reproduce the ISO standard text. Link and summarize at a high level.

Well-Tagged PDF (WTPDF)

PDF Association

Open specification for tagged PDF structure, accessibility and reuse in PDF 2.0.

Reuse note: Creative Commons Attribution 4.0. Can be reused with attribution and change notices.

Matterhorn Protocol 1.1

PDF Association

PDF/UA conformance testing model that translates PDF/UA into checkpoints and failure conditions.

Reuse note: Link and summarize unless the specific licence is confirmed before republication.

Revised Section 508 Standards

U.S. Access Board

Official U.S. federal ICT accessibility standards, including electronic content requirements.

Reuse note: U.S. federal material is often public domain, but check page-specific notices and third-party content.

Section508.gov PDF training

GSA / Section508.gov

Practical U.S. federal guidance on creating and remediating accessible PDFs.

Reuse note: Most material is free of copyright per Section508.gov policy, with caveats for restricted photos or third-party content.

ADA Title II Web Rule Fact Sheet

U.S. Department of Justice

Plain-language summary of the ADA Title II web and mobile app accessibility rule.

Reuse note: Link and summarize. Government material may be reusable, but preserve official context and check page notices.

Recommended standards reading order

Start with the ADA Title II fact sheet if you are a U.S. public-sector team.

Read WCAG 2.1 AA because it is the referenced technical standard for ADA Title II.

Use the WCAG quick reference to identify success criteria and PDF techniques.

Use PDF/UA and WTPDF to understand PDF-specific structure requirements.

Use Matterhorn to understand validation checkpoints and failure modes.

Use Section508.gov material for practical remediation training and U.S. federal context.

Frequently asked questions

Can pdfaa.ai republish the full WCAG or PDF/UA standards?

Not as a default approach. We can link to official standards, summarize them, and reproduce only material that is clearly licensed for reuse with the required attribution. ISO standards should generally be linked, not copied.

Which open document is most useful to reproduce or adapt?

The PDF Association Well-Tagged PDF specification is the strongest candidate because it is explicitly licensed under CC BY 4.0.