WCAG 2.1 Principles Explained: Robustness

Organizations of all sizes and industries have used the Web Content Accessibility Guidelines (WCAG) to make their website and web content more accessible to people with disabilities. In this fourth and final article in our WCAG series, we’ll discuss the principle of robustness and how it relates to making your website more accessible.

The Robustness Principle

In technology, something that is robust comes with a wide range of capabilities or is able to deal with many different situations. Robustness, as defined by WCAG, refers specifically to web content that is compatible with a variety of “user agents”: browsers, assistive technologies, and other means of accessing web content.

People with disabilities may view and interact with your website through any number of browsers: Google Chrome, Mozilla Firefox, Safari, Microsoft Edge (and its outmoded cousin Internet Explorer), and more. In addition, they may rely on different types of assistive technologies -- from screen readers and braille terminals to software for text magnification and speech recognition.

WCAG seeks to ensure that your website can accommodate all of these options and more. WCAG 2.0 includes two criteria for judging your website’s robustness:

• Parsing: The content and code of your website should be well-formed. For example, content written in a markup language such as HTML or XML should have complete start and end tags and should nest elements correctly. This will help prevent display errors and problems with assistive technologies.
• Name, Role, and Value: User interface components such as form elements can have their name and role “programmatically determined” by an assistive technology. In addition, people with disabilities can use assistive technologies to set values, properties, and states on your website.

What Developers Should Know About Robustness

To satisfy the first robustness criterion, you can use automated validation tools such as our automated compliance scan to find errors and warnings in your HTML and XHTML code.

The second robustness criterion can be satisfied automatically if you use semantic elements correctly for their intended purpose. If your website uses custom-built components, however, you will need to use WAI-ARIA roles to provide a description of the element’s function, such as “navigation,” “banner,” or “search.”

Robustness in WCAG 2.1

With only two success criteria, robustness is the shortest of the four WCAG 2.0 principles. WCAG 2.1, the new version of WCAG released in June 2018, includes an additional third criterion:

• Status Messages (4.1.3): Many websites make use of dynamic content such as status messages that are written in markup languages such as HTML and XML. This content must be presented to users of assistive technologies without necessarily receiving a visual focus. For example, if users are viewing their social media feeds, they can be alerted of a new post without the browser automatically scrolling up to display it to them.

Final Thoughts

Making your website robust in accordance with the WCAG standards ensures that it will be navigable and usable by as many people as possible. To learn more about how you can improve your WCAG compliance, follow the Bureau of Internet Accessibility blog for the latest news and updates, or get in touch for a free 30-minute consultation.