Standards for Accessibility

The following standards are designed to help authors understand the needs of people with disabilities and also the technologies to create universally accessible online resources.

  • W3C Web Content Accessibility Guidelines (WCAG): WCAG is used as an international standard for web, document and mobile technologies on the needs of people with disabilities in accessing electronic content.  There are 78 Success Criteria in WCAG 2.1 and they are organized within higher level Principles (4) and Guidelines (12).  Each success criteria is assigned a level of importance: Single-A, Double-A and Triple-A, with Single-A being the most important.   Most accessibility standards include primarily Single-A and Double-A requirements.
  • W3C Accessible Rich Internet Application (ARIA): ARIA markup is used to describe web page structure and the features of custom web  components to assistive technologies through the use of operating system specific accessibility APIs.  ARIA enables developers to communicate the features of custom widgets and keyboard support to people using screen readers and other types of assistive technologies.
  • W3C EPUB3: Digital Book Standards: Electronic books that conform to the EPUB3 standards can be highly accessible.  EPUB is based on HTML and ARIA technologies used for web pages and therefore use the same accessibility techniques.  EPUB is the format typically used to create accessible versions of electronic books for people using assistive technologies.  At Illinois the etext@illinois project and the ClassTranscribe projects use EPUB3 for creating accessible electronic books.
  • PDF/Universal Access: The Portable Document Format (PDF) is widely used in creating electronic documents.  PDF was originally designed to support printing documents consistently on a wide range of printers and therefore is based on a postscript type language to define shapes and forms rather than text and structure.  PDF accessibility features were added later in PDF development when accessibility became an issue and includes creating an additional “tagging” layer to describe the content to assistive technologies.  PDF/Universal Access defines this tagging structure and how it should be used to make PDF documents accessible to people using assistive technologies. NOTE: The accessibility of PDF documents is often considered difficult to discern and creating the tagging structure for untagged PDF documents can be time-consuming and tedious.

Interoperability and Universal Design

interoperability: ability of a system to work with or use the parts or equipment of another system
( Dictionary, Merriam-Webster, 2020)

The main purpose of information technology standards is the concept of interoperability.  Interoperability is the very foundation of the World Wide Web Consortium along with open standards to provide equal access to everyone to the benefits of web technologies.  Interoperability was the original mantra of Tim Berners-Lee, the inventor of the web and the Director of the W3C, to “write something once and have it accessed anywhere“.

Universal Design extends the concept of interoperability from “systems” to “people”.   People have a wide range of capabilities and preferences and we want authors to create web content that can adapt to the needs of people.  People with disabilities sometimes have more specific needs, for example a person who is hard of hearing needs captions on a video to understand the content.  But those same captions are useful to someone who is not a native speaker of the language spoken on the video to also make it easier for them to comprehend the content.  For someone who is blind or visually impaired have a text description of an image helps them understand the purpose of the image in a document.  This same text description is useful to everybody be giving people another way to understand the the information the author intended by including the image.   Universal Design is more than just for people with disabilities, but about creating content that is more useful and adaptable to the needs of everyone, including people with disabilities.

Common Problems

While the concept of interoperability has benefited many people using the web to allow people to use a wider range of technologies to access content, this is not true for people with disabilities.   Interoperability has improved in recent years for people using assistive technologies, like screen readers, but there are still many problems that make the web difficult and sometimes impossible for people with disabilities to use.  The problems are directly related to how authors create content and their limited their understanding of the principles of Universal Design.

Some of the common authoring problems:

  • Poor color contrast of text content.
  • Not including headings (H1-H6) to label document sections.
  • Not labeling form controls.
  • Not all functions of a page can be operated with the keyboard.
  • Not all content visible in operating system high contrast modes.
  • No captions and/or text transcripts available for video or audio content.
  • Not enough time to complete a task

Participate in Developing Standards

The University of Illinois is a member of the W3C which makes anyone who works for or attends the university eligible to participate in any W3C working group, not just working groups related to accessibility.