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21 June 2023

Accessibility: A follow up on principal guidelines

What are the main principles behind WCAG 2.0?

Earlier, we discussed the WCAG 2.0 (Web Content Accessibility Guidelines 2.0), which represent a set of internationally recognized guidelines for making web content more accessible to people living with disabilities. We covered the primary principle of perceptibility. The 4 principles of the WCAG rules are: perceptible, usable, understandable, and robust.

Second principle of the rules: Usability

Functionalities must be usable by everyone, including those using assistive technologies such as screen readers or alternative control devices. This includes elements such as keyboard navigability, predictability of behavior, ease of navigation and elimination of disruptive elements. Here are a few specific examples of how this principle can be applied:

  • If keyboard movement requires more than the use of a simple arrow or tab key, the user must be offered an alternative.
  • Speed of execution or typing rhythm should not be required but rather be specific to the user. Therefore, the time allowed to complete a task should not be a requirement of any given activity.
  • To avoid disrupting the user’s workflow, potentially disturbing elements such as repetitive flashes should be avoided.
  • Users must be provided with orientation elements to help them navigate, find content, and orient themselves. Section headings are one example.

Third rule principle: Understandable

Content and operation must be comprehensible to all. This means using clear, simple language, providing explicit instructions and error messages, and organizing content logically. There are a few best practices for making the user interface understandable:

  • Words that might be ambiguous, unfamiliar, or used in a domain-specific way should appear in a list of definitions, in a glossary or in some other appropriate way.
  • A term usually referred to by an abbreviation is written in its full form the first time it is used, paired together with the usual abbreviation, and its definition if required.
  • If the pronunciation of a word is vital to understanding its meaning, the pronunciation is given immediately after the word or via a glossary and sound link, as appropriate.
  • Users can choose to disable any type of substantial change, such as the appearance of a pop-up window or dialog box, an unexpected modification or any other change that might disorientate them or disrupt their path.

Web content must be robust enough to be correctly interpreted by a wide variety of users and intelligible to assistive technologies. This means using standardized technologies and avoiding coding practices that could lead to conflicting interpretations.

Fourth and final rule principle: Robustness

Transposing non-accessible content into content that is poses certain challenges. For some existing content, this is an unavoidable operation. The easiest and most effective way of addressing these challenges, however, is to design all new content in accessible terms from the outset.

You are now familiar with every principle associated with success criteria for achieving specific accessibility compliance objectives. It’s now up to you to apply them in your next training programs, so that as many collaborators as possible can have full access to all available information!


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