PDF/UA (PDF/Universal Accessibility) is the informal name for ISO 14289, the International Standard for accessible PDF technology. A technical specification intended for developers implementing PDF writing and processing software, PDF/UA provides definitive terms and requirements for accessibility in PDF documents and applications. For those equipped with appropriate software, conformance with PDF/UA ensures accessibility for people with disabilities who use assistive technology such as screen readers, screen magnifiers, joysticks and other technologies to navigate and read electronic content.
|Type code||'PDF ' (including a single space)|
|Initial release||15 July 2012|
(18 December 2014 )
On February 18, 2015 the US Access Board announced its Proposed Rule for US federal policy on accessibility, commonly known as Section 508. The proposed rule identifies PDF/UA as equivalent to WCAG 2.0 for "appropriate content".
PDF/UA is not a separate file-format but simply a way to use the familiar PDF format invented by Adobe Systems and now standardized as ISO 32000.
Requirements for conforming PDF files (Clause 7)
- Complete tagging of "real content" in logical reading order
- Tags must correctly represent the document's semantic structures (headings, lists, tables, etc.)
- Meaningful graphics must include alternative text descriptions
- Security settings must allow assistive technology access to the content
- Fonts must be embedded, and text mapped to Unicode
Requirements for conforming PDF processors (Clause 8)
- The ability to fully process tags and artifacts in PDF files
- The ability to announce relevant actions to users
- The ability to process and represent digital signatures, annotations and Optional Content
- The ability to navigate the document by a variety of means
Requirements for conforming assistive technology (AT) (Clause 9)
- The ability to represent information provided by a PDF/UA conforming reader to the AT user
- The ability to navigate the document by a variety of means
Audience & Benefits
While the PDF/UA specification is written for software developers, PDF/UA support is of interest to persons with disabilities who require or benefit from assistive technology when reading electronic content. With PDF/UA conforming files, readers and assistive technology, users are guaranteed – so far as the PDF format itself can provide – equal access to information.
The benefits of PDF/UA extend beyond people with disabilities. With support for PDF/UA, reader software will be able to reliably reflow text onto small screens, provide powerful navigation options, transform text appearance, improve search engine functionality, aid in the selection and copying of text, and more.
The PDF/UA project began in 2004 as an AIIM Standards Committee. The PDF/UA wiki, operated by AIIM, contains agendas, meeting-minutes and public-access documents pertaining to the development of PDF/UA.
Chaired since 2005 by Duff Johnson, in 2009 AIIM's PDF/UA Committee became the U.S. Committee for ISO/AWI (Accepted Work Item) 14289 with Cherie Ekholm of Microsoft as International Project Leader.
The US Committee continued as the main driver of the standard's development through the WD, CD, DIS and FDIS Phases of ISO standards development, with review, comment and balloting by the member bodies of ISO TC 171.
In October 2012 the US Library of Congress added PDF/UA to their list of archivable file formats. The LoC's guidance states that PDF/UA is "...a preferred format for page-oriented content by the Library of Congress."
AIIM's US Committee for PDF/UA has published the following documents in support of PDF/UA:
Ongoing ISO and AIIM Committee Activities
Work on ISO 14289-2 (PDF/UA-2) is ongoing. PDF/UA-2 will be based on PDF 2.0.
Committee Organization & Leadership
- Project Leader, International Committee: Duff Johnson, Independent Consultant and Executive Director of the PDF Association
- U.S. Chair & Spokesperson: Duff Johnson, Independent Consultant and Executive Director of the PDF Association
- TC 171 SC 2 WG 9 Secretary: Betsy Fanning, Standards Director at AIIM
- Convener, International Committee: Matthew Hardy, Adobe Systems
Participation by subject matter experts, software developers and other interested parties is invited and encouraged.
PDF Association Activities
The PDF Association helps promote PDF/UA in a variety of ways.
PDF/UA Competence Center
In 2011 the PDF Association created the PDF/UA Competence Center as a way for vendors to develop educational resources and share experiences regarding implementation of PDF/UA. The Matterhorn Protocol (see below) is a product of the PDF/UA Competence Center.
NVDA goes PDF/UA Project
In 2012 and 2013 the PDF Association helped raise money and awareness for NV Access's NVDA to further development of the world's first PDF/UA conforming screen reader.
The Matterhorn Protocol
In August 2013 the PDF Association's PDF/UA Competence Center published the Matterhorn Protocol, a set of 31 checkpoints and 136 failure conditions to help software developers make it easier for document authors to create fully accessible PDF files and forms.
The PDF/UA Reference Suite
In June 2014 the PDF Association's PDF/UA Competence Center published the first iteration of the PDF/UA Reference Suite, a set of reference-quality documents conforming to PDF/UA-1.
The Tagged PDF Best Practice Guide
Seminars, Books and Brochures
The PDF Association conducted numerous educational seminars on PDF/UA throughout Europe, North America and Australia in 2012 and 2013. A book, "PDF/UA in a Nutshell", was produced in both English and German. An informational brochure was also produced in both languages.
- The US Committee for PDF/UA
- What is PDF/UA about anyway?
- PDFlib whitepaper: "A Technical Introduction to PDF/UA (PDF)
- Board Proposes Updated ICT Accessibility Requirements
- A new standard for PDF accessibility: PDF/UA
- PDF/UA in a Nutshell
- The PDF/UA standard for universal accessibility
- WCAG 2.0 PDF Techniques
- WCAG 2.0 and PDF/UA - your questions answered
- PDF/UA-1:2014 now published!
- ISO 14289 from iso.org
- ISO 14289 available from ISO.org
- PDF/UA on the Library of Congress's Digital Preservation website, checked 2013-10
- Adobe Systems' Statement on WCAG 2.0 and PDF/UA
- ISO 14289 on iso.org
- AIIM / ANSI / ISO 14289-1:2016
- Achieving WCAG 2.0 with PDF/UA
- PDF/UA-1 AIIM's Technical Implementation Guide to PDF/UA
- PDF/UA-1 Technical Implementation Guide: Understanding ISO 32000-1 (PDF 1.7)
- PDF Standards Wiki
- PDF/UA Competence Center
- NVDA goes PDF/UA! The PDF Association Steps Up to Fund Development of the World's First PDF/UA Conforming Screen Reader
- "The Matterhorn Protocol". PDF Association. Retrieved 2014-06-18.
- "The PDF/UA Reference Suite". PDF Association. Retrieved 2014-06-19.
- PDF/UA Competence Center Tagged PDF Best Practice Guide
- The PDF Association's PDF/UA in a Nutshell
- PDF Association brochures
- ISO's webstore page for ISO 14289-1:2014
- ANSI's webstore page for ISO 14289-1:2014
- AIIM's webstore page for ANSI / AIIM / ISO 14289-1:2016
- AIIM's PDF/UA page
- The PDF Association's PDF/UA Competence Center
- List of software supporting PDF/UA
- Accessible PDF: A Glossary of Terms
- Video recordings from the PDF/UA sessions at the PDF Association Technical Conference 2012 in Basel, Switzerland
- Make a PDF document accessible from Adobe InDesign and Acrobat Pro
- Make a PDF document accessible from Microsoft Word