Flashing content does not flash more than three times in any one second period, or the flash is below the general flash and red flash thresholds

Design and Developer Notes

Flashing content can cause seizures for people with photosensitive epilepsy. This type of content is most often encountered in video content (e.g. flash photography).

Flashing content may also appear in some transitions or notifications.

Note that this criterion refers to repeated flashing (more than 3 flashes in a second).

Testing Notes

Ensure there is no flashing content on the page

Note any content that appears to flash. Transitions and fades are acceptable, but content that repeatedly flashes between contrasting colours must not be used.

Steps to check

Examine pages for any content that flashes more than 3 times in a second.

WCAG Reference: Understanding Success Criterion 2.3.1 Three Flashes or Below Threshhold