Flicker from a faulty street light in Calgary, Canada, resulted in a seizure when Kathryn Mackay was inadvertently exposed to the flashing light.  While the story is exceptional, it illustrates the danger of low frequency flicker, especially for those prone to seizures.

This last weekend, Mackay suffered a grand mal seizure after catching an unexpected glimpse of the street light. The Tuxedo Park resident fell during the episode, striking her head on the ground. The subsequent gash over her right eye required stitches to close.

Read the full story here.