Assistive technology for in-depth testing

PDF/UA in a Nutshell

  • NVDA 2012.3.1 (Non Visual Desktop Access) is a portable, open-source screen reader available in over 40 languages, developed by NV Access. It supports spoken output and/or Braille displays.
  • JAWS 14 (Job Access With Speech), developed by Freedom Scientific, is a widely-used commercial screen reader for Windows. It has been specially designed to work with a number of applications and supports spoken output and/or Braille displays.
  • ZoomText 10 Magnifier is the most widely used text-enlargement software for partially-sighted users. It was developed by the American company AiSquared.
  • COBRA Professional 10 from Baum Retec) is a popular software solution for combining screen enlargement with spoken and Braille output.
  • WYNN is a program from Freedom Scientific aimed in particular at helping users with reading and writing difficulties. By reading text aloud while highlighting each word as it is spoken, young people with dyslexia and other learning difficulties can develop and eventually master their written language skills.

Compliant reader software

So far, there are no PDF programs or assistive technologies which offer full PDF/UA compliance when providing access to tagged PDF documents. One particularly important reason for this is that the standard is still very new, meaning that corresponding software development has only just begun. Adobe Systems and the not-for-profit Australian organisation NV Access have officially announced their support for PDF/UA and are now working on implementing it in their products.

The first PDF/UA-compliant assistive technology is expected to be the screen reader software “Non Visual Desktop Access” (NVDA). NVDA was developed by NV Access as a portable, open-source screen reader. It allows blind and partially-sighted users to interact with the Windows operating system and the applications it runs, as well as use PDF documents and the internet, using the synthetic speech function eSpeak, optional Braille output, and other functionality. eSpeak supports more than 40 languages, and other languages and voices can be added using the SAPI interface. The NVDA screen reader can be downloaded for free from the developer’s website – – after which it is easy to install.

At present (as of mid-2013), NVDA is already mostly PDF/UA-compliant. NV Access, the PDF Association and the Swiss-based Access For All foundation are currently working together to further develop the software, to ensure future versions will meet all PDF/UA requirements in full.

Of the PDF software available today, the free Adobe Reader and the paid Adobe Acrobat currently provide the greatest level of compliance with the standard. The current version, Adobe Reader XI, is mostly PDF/UA compliant – albeit only under Windows.

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About PDF Association

Founded in 2006 as the PDF/A Competence Center, the PDF Association exists to promote the adoption and implementation of International Standards for PDF technology.

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