2.3.1 Three Flashes or Below Threshold: Web pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds. (Level A).
This applies to native apps by replacing “Web pages” with “Apps”.
Requirements
Content does not flash more than three times a second.
Why is it important?
- Visual flicker, flashing and strobe lighting can affect anyone, but some users will be more susceptible than others.
- Symptoms may include eyestrain, dizziness, fatigue, headaches, migraine, and nausea.
- Users with medical conditions such as Ménière’s or photosensitive epilepsy can be severely affected, experiencing vertigo, hearing loss and seizures.
Summary
Do not show anything that flashes more than three times a second.
A page must not contain content that flashes more than three times a second.
Common mistakes
Content flashes at more than three times a second.