Electronic Accessibility

Last updated: 5/26/2025

Certain visual events, like rapidly flashing lights, flickers and strobe effects, can trigger seizures and other vestibular disorders.

WCAG 2.3.1 Three Flashes or Below Threshold (A) works to prevent the most harmful of these occurrences, by forbidding anything that flashes or flickers more than three times within a second, but it may be worth limiting or avoiding other visual events that are less harmful but still impact learners who have vestibular conditions and other cognitive disabilities.

With this in mind, it's recommended that you be thoughtful about which animation effects you include in eCourses and how you time them. Effects that are particularly visually dynamic — like Spin & Grow, Bounce, Random Bars, looping motion paths and others — may trigger vestibular conditions, especially if they occur quickly (i.e., with a shorter duration) and/or occur at the same time as other animation effects.

Fade is generally one of the safest animation types to use, and whatever effects you use, the less rapidly they occur, the less likely they are to interfere with learners’ experiences.