2.2.2 Pause, Stop, Hide: For moving, blinking, scrolling, or auto-updating information, all of the following are true: (Level A)
- Moving, blinking, scrolling: For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and
- Auto-updating: For any auto-updating information that (1) starts automatically and (2) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto-updating is part of an activity where it is essential.
- Avoid moving, blinking scrolling content if possible.
- Content should not blink more than 3 times per second, if it does blink 3times per second then it is considered as flashing & will fail WCAG.
- Auto updating content should be provided with a pause button or provide a mechanism for the user to specify when the update can happen.
- If the entire page contains moving, blinking, scrolling & auto updating content then pause, stop or hide buttons are not required as there is no parallel content.
- Animation that conveys the users that a page or content is loading doesn’t require to meet this success criterion.
This success criterion intends to avoid distractions when the users are interacting with any web page. Moving. Blinking an automatically updating contents such as motion pictures, animations, real-time games, multimedia presentations and auto-updating stock tickers cause problems for screen reader users, users with reading difficulties, low vision users, users with attention deficit disorder and other cognitive disabilities while they operate and consume the content.
This success criterion doesn’t prevent such contents with such designs being used. But it just instructs that Blinking, moving & scrolling content that lasts more than 5seconds and Parallelly presented must be provided with pause, stop or hide button. While blinking content is not equivalent to flashing content if the content that blinks more than 3 times per second it is considered as flashing content. It is a best practice to avoid content that is blinking, moving or scrolling.
When Auto updating content is found on news websites, live sports sites that update scores etc., even this content should be provided with pause button or provide a mechanism where the user can set the interval of when the update of the live region can take place. Sometimes the auto updating content might refresh entire page or only the portion of the content that is being updated. Note that when a live score or such live update happens and if the user resumes from pause state, it is not necessary to resume where the user has paused but to resume where the live event is at the point of resume.
Well explaned Raghava.