2.3 Seizures and Physical Reactions
Do not design content in a way that is known to cause seizures or physical reactions.
2.3.1 Three Flashes or Below Threshold
Conformance level: A
Do not include content that flashes more than three times in one second.
The flash size should not be too large. The flashing area should occupy less than 25% of any 10-degree visual field on the screen.
Red flashing is more likely to cause seizures. Especially when combined with high contrast.
2.3.2 Three Flashes
Conformance level: AAA
Avoid content that flashes more than three times in one second.
2.3.3 Animation from Interactions
Conformance level: AAA
Provide a mechanism to disable non-essential animations triggered by interactions.