Flashing is generally a bad idea. It can cause all sorts of issues, from seizures to motion sickness. If you absolutely must have a flashing element there are a few things to consider.
- Failure at any step constitutes a 508 compliance issue
- Look for elements that contain flashing
- Scrolling or blinking text
- Scrolling or blinking page elements
- Videos that contain flickering or flashing
- GIFs that contain flickering or flashing
- Check if you can determine the frequency of "flashing."
- Check that the rate of flashing is less than 3 Hz (3 times a second), or scroll delay is set to >= 400.
Failure: This blinking text fails because the rate of flashing can't be determined and its greater than 3 Hz.