Flickering, Blinking, and Moving content

Requirements

• Images do not flicker at a rate that may trigger seizures in susceptible individuals.
• Movement on the page is limited to 5 seconds.
• Placing a control on the page that stops moving, blinking, or auto-updating content will satisfy these criteria.
• Provide a link button or other mechanisms that reload the page without blinking content.

Full Explanation

2.2.2 Pause, Stop, Hide (Level A) Moving Images

This guideline ensures that moving or auto-updating elements on a page can easily be paused, stopped, or hidden and not distract users from reading, navigating, or interacting with the rest of the page. Remove distractions so that people find concentrating easier while performing a task.

Exceptions

Essential activities, e.g., real-time traffic information or weather warnings.

Seizures

Designers must not create content that is known to cause seizures.

2.3.1 Three Flashes or Below Threshold (Level A)

This guideline is to ensure there are no more than three flashes within one second on a page. Flashing or blinking content on a page can trigger seizures in people with photosensitivity. Examples include a video or animation of strobe flashes.