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.
Note: Since any content that does not meet this success criterion can interfere with a user’s ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.
Understanding Success Criterion 2.3.1: Three Flashes or Below Threshold
If we had a category named “We absolutely cannot screw this up” this criterion would be in it, because failing this criterion causes seizures in people who have Epilepsy.
Checklist – System Foundations
Iconography
Animated images
| Test | Priority | Automated test? |
|---|---|---|
| Do flashing elements flash at a rate of less than 3 Hz (3 times per second) | High | None |
Checklist – Components
Video – Recordings
| Test | Priority | Automated test? |
|---|---|---|
| Do flashing elements flash at a rate of less than 3 Hz (3 times per second) | High | None |