Many people ask how we make our PDFs accessible and what is the difference between Accessible PDFs that adhere to WCAG2.0 guidelines or PDF/UA standards.
PDF is almost 25 years old
The Portable Document Format (PDF) has been in existence for almost 25 years. Appearing in the early 1990’s originally from software developer Adobe Systems, the intent was to provide a document format for sharing, formatting, and publishing content and images among computer users of disparate platforms who may not have access to mutually-compatible application software. However, since it was developed years before “the internet was born” it became a pseudo document standard on electronic platforms.
Adobe sets PDF free
While Adobe Systems made the PDF specification available free of charge in 1993, PDF was a proprietary format, controlled by Adobe, until it was officially released as an open standard on July 1, 2008, and published by the International Organization for Standardization as ISO 32000-1:2008, at which time control of the specification passed to an ISO Committee of volunteer industry experts.
Different PDF ISO standards
Since then various other sub-sets of that standard have been developed. These standards are used to specify how specific aspects of that standard may be used in precise ways to meet industry needs. These include:
- PDF/E (ISO 2457), which is a PDF standard specifically for Engineering documents and their requirements
- PDF/X (ISO 15929 and ISO 15930), which is a PDF standard that is specifically intended for the Graphic Arts, Pre-press environments to convey digital data for those environments.
- PDF/VT (ISO 16612-2), which is another Graphic Arts focused PDF standard that also includes specifications for variable data and transactional data.
- PDF/A (ISO 9005), which is a PDF standard specifically for long term PDF preservation for archiving
- And PDF/UA (ISO 14289), which is a PDF standard specifically intended to make the content within a PDF available for accessibility.
Enter WCAG – Web Content Accessibility Guidelines
With the need for accessible web sites, Web content Accessibility Guidelines (WCAG) were also developed. These guidelines were mainly aimed at making web pages and web content accessible to disabled users, using assistive technologies and emerging technologies such as smartphones.
WCAG 1.0 was published in May 1999 followed by WCAG 2.0 in 2008 which was accepted as an ISO Standard – ISO/IEC 40500: 2012 in 2012.
WCAG 2.0 is a guideline that covers a broad range of requirements from visual, audio output, cognitive challenges, and even some guidelines for PDF Accessibility.
It is important to note that PDFs can be compliant to WCAG 2.0 guidelines and to the PDF/UA standard. A considerable amount of effort went into mapping WCAG 2.0 guidelines to the specific sections of PDF/UA standard, thus ensuring WCAG compliance by following the precise specifications within the ISO standard.
As a result AIIM (Association for Information and Image Management), the governing body for ISO standards, published a document that shows how to achieve WCAG 2.0 through the use of the PDF/UA standard.