Some content with flashing, blinking, flickering or rapidly changing colors can cause seizures in susceptible individuals. The best practice is to avoid using any content that flashes, flickers or rapidly changes color, but if the content is necessary, make sure it adheres to the following rules:
- It does not flash more than three times in one second.
- It is below the general flash and red flash thresholds.
Flash thresholds are different for each color; people are more affected by red flashes than any other color.
Even if the user isn’t susceptible to seizures or the flash is less than three times in one second, flashing content is generally distracting. The safest and most accessible option is to avoid using flashing content.