Understanding Interruptions (Minimum)


This section contains the main explanatory content of the Understanding. It explains why the Guideline or Success Criterion exists and, at a high level, how to meet it.

The intent of this Success Criterion is that people with impaired attention and memory can complete a task. When users are interrupted, they may forget what they are doing and abandon the task. This can happen even when the original task is extremely important. For example, a user is making a doctor's appointment, but interruptions cause the user to forget what they were doing and the critical appointment is not made.

From Etsi “Presented information is free from distractions if the information is presented so that required information will be perceived without other presented information interfering with its perception. Distractions from a user's point of view can result from distracting events and from information overload. Freedom from distraction involves minimizing distractions and avoiding distractions.”

Where a site may generate interruptions and changes of content, the user must be able to easily turn them off to control them, such that:

  1. Interruptions can be easily controlled and turned off
  2. Secondary content (such as special offers or complementary material) can be easily identified, controlled and turned off
  3. No sudden changes occur on the site
  4. Media events can be easily controlled and turned off
  5. Chat can be easily turned off and on again
  6. Non-critical messages can easily be turned off and on again
  7. Where standard techniques exists for the above, they should be used
  8. Further pop-ups and similar distractions must always be easy to close and avoid so that all people can continue their task.

It is worth noting that the task force is proposing semantics to support an integrated solution. This is a proposal to help people stay focused and productive. It is based on a matrix for distractions at the operating system, browser, or cloud level. Currently people can turn off distractions such as Skype, and Facebook, across different devices, and then may forget to turn them back on. This idea manages all distractions by forming a cross-application and cross-device distraction matrix that manages all distractions in one setting. People and users can be clustered in terms of importance or groups. For example, the CEO and your child's care giver could both be considered critical contacts. So even if they do not feel the message is urgent, they can sometimes disrupt the user anyway. Some family members and important colleagues can be in another group, friends and extended family in a third group, system messages from the compliance system can be a different group again.

Dimensions in the matrix can include: Groups of contacts, how urgent the contact feels any message is, and the level of interruptions the user can tolerate at any given time or setting. The user can set how to handle any combination of the above for the level of concentration needed at the time. For example, during normal work hours, messages from important colleagues could interrupt the user, but any other messages would get logged and read when the user has time. In another example, the user may be giving a talk and sets the interruption level to critical. Then, only critical messages from key colleagues and family can interrupt (for example, messages that a critical contact feels are critical and urgent). Default systems can include setting work hours. Optionally, distractions such as news websites could also be limited in low distraction times.

Further pop-ups and similar distractions must always be consistently easy to close and avoid so that all people can continue their task.


This explains how following the success criterion benefits particular types of users with disabilities.


Examples in Understanding pages are normally simple lists of hand-waving examples. Sometimes, examples are instead provided in sub-sections with headings. In either case, examples should stay high-level and not get into code specifics, which is for techniques.




This section references techniques that can be used to meet the Guideline or Success Criterion. There are sub-sections for sufficient techniques, advisory techniques, and failures.

Remove any parts of the template that are not used, such as the section and heading for situations, sub-lists of techniques, or the "AND" construction. Also remove the square brackets around placeholder optional components.


Techniques that are sufficient to meet the Guideline or Success Criterion.



Techniques that are not sufficient by themselves to meet the Guideline or Success Criterion.

Same template as sufficient techniques.


Techniques that document conditions that would cause the page not to meet the Guideline or Success Criterion, even if sufficient techniques are also used.

Same template as sufficient techniques.