Three Flashes or Below Threshold
Success Criterion 2.3.1 (Level A)


Have you ensured that your website/application does not contain content that flashes?

Why is this important

Content that flashes can trigger seizures in users who suffer from photosensitive epileptic seizures. In addition, flashing content can be a distraction for learners with cognitive/learning disabilities, and can also frustrate users in general.

Whom does it benefit?

Example 1:

As a person with epilepsy,
I want web content presented to me without flashing or fast blinking,
so that I can access the information without the potential of triggering a seizure.

Example 2:

As a student with an attention deficit disorder,
I want information presented without unnecessary distractions,
so that I can concentrate and focus on the assignment at hand.

What should you do?

Do not design content that flashes.

While WCAG allows for content that flashes under certain, very strict parameters, it is strongly suggested to refrain from using flashing content at all. The rationale being that one must measure the size of the visual field and viewing distance, along with timing of flashes and luminosity. It becomes a very complex formula to verify that any flashing content is within an acceptable threshold and can be easy to miscalculate.

Furthermore, in the type of educational content that Pearson produces, there is no need to use flashing or blinking content. Therefore, adding any sort of flashing content could be hazardous and of very little gain for the end users.

How do you do it?

Flashing content should not be used anywhere. If already in existence, remove the flashing content and replace with non-flashing content that conveys similar meaning or information.

Need technical guidance?