The Australian Government's study into the Accessibility of the Portable Document Format for people with a disability
People with disabilities face challenges in dealing with the online world. In order to participate in the online world they employ many adaptive strategies and use a range of tools commonly known as assistive technologies. These include text to speech software and screen magnifiers to name a few. The way information is presented online by government and others can make it difficult for assistive technology to do what it needs to. Many technologies have accessibility issues but the Portable Document Format (PDF) is the one most often the subject of web accessibility complaints.
The Australian Human Rights Commission (AHRC) considers Portable Document Format (PDF) files to be generally inaccessible to people with a disability. Since 2000, the AHRC has maintained this strong position and their Disability Discrimination Act: Advisory Notes recommend alternatives be provided when PDF files are used1. To date, the Australian Government has supported this position.
Internationally, perspectives on the accessibility of PDF files are unclear and there is no agreed definition about what constitutes an ‘accessible PDF’. Notwithstanding this, technical advances in the Portable Document Format and improvements in the assistive technologies used by people with a disability are having a major impact on the policy debate.
The Australian Government’s recent endorsement of the World Wide Web Consortium’s (W3C) Web Content Accessibility Guidelines (WCAG) version 2.0 provides a renewed commitment by the Government to web accessibility. To enable the Government to conform to WCAG 2.0 and meet its obligations, particularly in relation to the Disability Discrimination Act 1992 (Cwlth) (DDA) and the United Nations Convention on the Rights of Persons with Disabilities (UNCRPD), a clearer understanding of the implications of using PDF files is required.
It is clear that there is a need for a greater understanding of the way PDF files are accessed by commonly used assistive technologies and the implications in using the Portable Document Format, via various adaptive strategies, by people with a disability.
To address the need for greater clarity on the issue, Vision Australia was commissioned by the Australian Government to undertake this study (the Study). It included a series of user consultations to understand the situational context in using PDF files, followed by technical evaluations assessing the functionality of the most commonly used assistive technologies when interacting with PDF files. The outcome of the consultation and results of the technical evaluations were then tested by people with a disability employing various adaptive strategies to gain an understanding of their experience when interacting with a selection of PDF documents.
It is important to note that accessibility is largely based on situational context. The Study showed there are a number of drawbacks in relying on technical evaluations as the sole determinant of accessibility. While technical evaluation might indicate a product is accessible, the user’s experience in whether they can achieve their specified goals with effectiveness, efficiency and satisfaction is the most important measure of accessibility.
Overall, the Study found that there is insufficient evidence to establish that the development of the Portable Document Format and improvements in assistive technologies have advanced enough for PDF files to be considered accessible for people with a disability, particularly for those who are blind or have low vision.
Importantly, the Study also highlighted that the issues contributing to the inaccessibility of PDF files, when used with assistive technologies, are not in general directly attributable to the Portable Document Format itself. The issues that result in an inaccessible PDF file are, in order of impact:
- the design of the PDF file by the document author to incorporate the correct presentation, structure, tags and elements that maximise accessibility;
- the technical ability of the assistive technology to interact with the PDF file (via the relevant PDF Reader); and
- the skill of the user and their familiarity with using their assistive technology to interact with a PDF file.
It should be noted that access to information in any file format, not only PDF, is significantly diminished for assistive technology users if there is no consideration given to these three issues. This Study focused solely on the Portable Document Format as this format is most often the subject of web accessibility complaints.
Furthermore, other than WCAG 2.0 Success Criteria, the Study could not identify an agreed definition on what constitutes an accessible PDF file to enable its accessibility across a wide range of assistive technologies. While the Study identified a body of work being undertaken to establish a set of guidelines for the creation of accessible PDF files by the PDF Universal Access Committee (PDF/UA), the guideline is in draft and not due for release until at least 2011.
As the Government recently endorsed WCAG 2.0, the Study used a number of WCAG 2.0 Success Criteria in the technical evaluations to determine if the use of PDF files with assistive technologies could claim conformance against the Guidelines. Until further data is available on the characteristics of an accessible PDF file and there are Sufficient Techniques available to support the conformance of the PDF technology to WCAG 2.0, the Australian Government position recommending that alternative file formats be provided whenever PDF files are used should remain unchanged.
User consultations (Vision Australia)
- PDF files are used by a wide variety of organisations and are commonly encountered. People who are blind or have low vision experience a high number of problems when accessing and interacting with PDF files, particularly with PDF files using multi-column designs;
- Users did not understand the need or reason for information to be provided in PDF, particularly given the difficulties they experience using these files (i.e. supplying newsletters in PDF files was considered unnecessary);
- Users have no way of knowing if a file had been created in an accessible way before downloading and opening it;
- Screen readers are unable to interact with a document saved as an image only PDF file because images are not accessible to people who are blind. Poor quality scanned documents are also inaccessible to users who have low vision, as the ability to view and read a scanned PDF deteriorates when magnified;
- To overcome problems using PDF files, a range of alternate methods are often employed, all of which require additional software, more time and extra effort and often have limited success;
- Employing workaround methods to access inaccessible PDF files results in a degraded experience when compared to accessing equivalent documents in other formats; and
- PDF support in some assistive technologies was perceived as nonexistent (Braille Notetakers and DAISY player).
Public online consultation (AGIMO)
- 80% of respondents do not support the use of PDF files without alternate formats;
- Submissions made by people working in the field of web accessibility provide conditional support for the use of PDF files providing they are used appropriately, created accessibly and properly tested;
- Government submissions revealed that the use of PDF files was prolific and not always appropriate, but noted the Portable Document Format was still preferred over other formats;
- Misinformation about the accessibility of the Portable Document Format exists
and there is a significant lack of awareness on:
- when it is appropriate to use the Portable Document Format;
- how to author or create more accessible PDF documents;
- how to validate the accessibility of a PDF file; and
- the impact that poorly created PDF files have on people trying to access them.
- There is a need for updated, specific guidance on the use of PDF files and how to create them more accessibly;
- The responsibility of document creators to consider accessibility was a strong theme in most submissions; and
- The importance of the user experience confirmed the critical role that user testing must play in the development of accessible web content.
Common assistive technologies
- Limited statistical data is available about the number of people using assistive technologies, and the type and versions they are using;
- The number of assistive technology users in Australia reported is relatively low compared to the number of people who are blind or have low vision;
- Vendors and disability organisations indicate that ZoomText is the most commonly used screen magnification software and JAWS is the most commonly used screen reader;
- The usage of portable Braille Notetakers (BrailleNote and PAC Mate) is relatively low; and
- Australian and international research shows the emergence of several free or low-cost screen reader options (NVDA, VoiceOver and SATOGO) that are starting to penetrate the market.
- Most vendors claimed to provide support or functionality in line with other formats (e.g. HTML or Microsoft Word);
- Assistive technology development is guided by emerging technologies and industry trends, and the core focus for research and development is now moving towards Web 2.0, Accessible Rich Internet Applications (ARIA and HTML 5);
- Most vendors felt that the responsibility for PDF accessibility lies with document authors;
- More accessible PDF files are required before vendors justify further research and development time for PDF over other emerging technologies;
- Adobe Reader is the most commonly-used PDF reader; developments to this application have enabled better support for assistive technologies ; and
- Support for PDF files was limited in earlier versions of assistive technologies (e.g. prior to JAWS version 8).
- The limitations of assistive technologies in interacting with PDF files, were not well documented prior to this Study;
- Based upon the Adobe Test Suite evaluation and statements provided by vendors :
- 33% of the most common assistive technologies used in Australia provide sufficient technical capability to interact with a PDF file (demonstrated through technical testing and vendors claims); these assistive technologies are JAWS, MAGic and ZoomText; it is estimated that these products are used by 89% of the assistive technology user population; and
- 66% of the most common assistive technologies used in Australia provide partially sufficient or not sufficient technical capability to interact with a PDF file (i.e. partially or completely failed technical testing); these assistive technologies are PAC Mate, BrailleNote, NVDA, SATOGO, Voice Over and Window-Eyes; it is estimated that these products are used by 11% of the user population;
- Of the assistive technologies that provided sufficient technical capability, JAWS (version 8 onward), was the only screen reader that successfully completed technical testing;
- The magnification component of ZoomText (versions 8 & 9) and MAGic (versions 9.5 – 11) provided sufficient technical capability based upon the Adobe Test Suite evaluation and vendor statements;
- No portable assistive technology devices commonly used in Australia currently provide sufficient support for PDF files; and
- As at August 2010, there are no Sufficient Techniques available for the Portable Document Format to support WCAG 2.0 conformance.
- PDF files that have been optimised for accessibility provide an enhanced user experience;
- Assistive technologies that provided sufficient technical capability (in interacting with a PDF file) still present usability issues that impact on a user’s ability to interact with PDF files;
- Issues encountered by the participants during the user experience were not, in general, directly related to the Portable Document Format itself. The issues that result in an inaccessible PDF file are, in order of impact: the design of the PDF file, the technical ability of the assistive technology, and the skill of the user;
- Participants achieved a 90% success rate for tasks completed on the documents optimised for accessibility (collection A) and a 60% success rate for tasks completed on PDF files representative of government documents (collection B);
- The time taken to complete the tasks was more acceptable when using the documents optimised for accessibility;
- People who are blind and use screen readers experience the greatest difficulty in accessing and interacting with PDF files and this group also experienced on average, a higher number of issues compared to all the other disability groups; and
- Some functionality provided by JAWS for other formats was not available for the Portable Document Format, e.g. users were unable to navigate the PDF files by paragraph.
The findings of the Study raise the need for:
- An updated position on the use of PDF files on government websites; including a review of the use of PDF files when the PDF/UA standard is released and Sufficient Techniques become available to satisfy WCAG 2.0 conformance;
- An internationally-agreed position on the characteristics a PDF file must have for optimal accessibility and a transparent indication of the time and skill required to create such files;
- A study into the impact (cost and resource implications) in creating accessible PDF files;
- Better resources and tools to support people in the creation of accessible PDF files, including clear and centralised guidance for government agencies on:
- appropriate use of the Portable Document Format;
- how to optimise PDF files for greater accessibility;
- the importance of testing PDF files for accessibility;
- Education programs, for authors and publishers of government documents, that include:
- the impact of inaccessible web content on people with a disability;
- information about assistive technologies and how they are used;
- advice on how to author documents for online publication; and
- Government agencies to:
- examine their use of PDF documents;
- examine their workflow process in the creation of PDF files;
- continue to offer a choice of file formats.
The Australian Government’s Web Accessibility National Transition Strategy (NTS), released in June 2010, addresses many of the conclusions raised in this Study. The NTS sets out a 4 year work plan for the transition to and adoption of WCAG 2.0. In implementing the NTS governments agencies will need to ensure that the technologies and file formats in use on their websites conform to WCAG 2.0.
The NTS work plan specifically addresses electronic publishing processes, training and education about accessibility issues.
Supporting the Government’s implementation of the NTS, AGIMO are providing resources, advice and guidance for government organisations on its Web Publishing Guide. Complementing the Guide, AGIMO hosts a collaborative community of expertise for people to share their expertise about accessibility and discuss issues. The accessibility of PDF files with assistive technologies will become a dedicated topic of discussion and guidance following the release of this Study.
- Australian Human Rights Commission, 2009, World Wide Web Access: Disability Discrimination Act Advisory Notes, viewed 5 April 2010, http://www.hreoc.gov.au/disability_rights/standards/www_3/www_3.html
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