WCAG 2.1 Principles Explained: Operability

The Web Content Accessibility Guidelines (WCAG) are used by businesses around the world to ensure that their websites and other internet-based content remain usable by people with disabilities. WCAG is organized around four main principles: perceivability, operability, understandability, and robustness (POUR).

In our previous blog post, we discussed the first principle of perceivability. We’ll continue the series with the second principle: operability.

The Operability Principle

WCAG’s emphasis on perceivability ensures that users can passively take in and access the information on your website. Operability, on the other hand, also guarantees that users can interact with and make full use of the site.

For example, Guideline 2.1 of WCAG requires websites to be fully functional and navigable with only the keyboard. This is particularly important for users with motor disabilities, who may not have the fine motor skills required to operate a mouse.

Users should also be given enough time to perceive and use your site’s content. They should be able to adjust, pause, or disable time limits, unless the limit is absolutely necessary or longer than 20 hours.

Another consideration is navigation; your website should be as easy to navigate as possible. It should use consistent, clear titles, subtitles, and headings. If users are pressing the Tab key to redirect focus to different elements, the order in which elements receive focus should make logical sense (such as a top-to-bottom ordering on the page).

Finally, to avoid seizures in users with conditions such as epilepsy, your site should not have content that flashes more than three times per second.

What Developers Should Know About Operability

Most modern browsers allow users to navigate focusable elements via the keyboard and activate them using the Enter/Return key. Make sure that you do not override this behavior or use an illogical focus order.

Your site’s HTML code should use semantic tags such as <section> and <aside> that make it easier for assistive technologies to understand the structure and meaning of each page.

Operability in WCAG 2.1

The latest version of the WCAG standards, WCAG 2.1, expands on its predecessor WCAG 2.0 with many new requirements for operability:

• Character Key Shortcuts (2.1.4): Keyboard shortcuts that use a letter, punctuation, number, or symbol can be turned off or changed to use keys such as Ctrl and Alt instead.
• Timeouts (2.2.6): Websites must inform users of how much time they have before inactivity leads to data loss, unless the time limit is longer than 20 hours.
• Animation from Interactions (2.3.3): Users can turn off animations and videos, unless they are essential to the website’s functionality.
• Pointer Gestures (2.5.1): Users can replace complex gestures such as pinching and swiping with simpler gestures such as taps and long presses.
• Pointer Cancellation (2.5.2): Users must be able to easily cancel an accidental “down event” such as a click, tap, or long press.
• Label in Name (2.5.3): A label’s visible text and accessible name must match each other.
• Motion Actuation (2.5.4): Functionality that is accessible through motions such as shaking your mobile device must also be accessible through the user interface.
• Target Size (2.5.5): In most cases, clickable elements must be at least 44x44 pixels.
• Concurrent Input Mechanisms (2.5.6): Users should be able to switch between multiple input mechanisms, such as touch, keyboard, mouse, and speech.

Final Thoughts

When applied in combination with the other three WCAG principles, operability ensures that people with disabilities can enjoy full use of your website. To learn more about the WCAG requirements, follow the Bureau of Internet Accessibility blog for the latest news and updates, or schedule a free 30-minute consultation with our internet accessibility experts.