Requirement 6
Don’t use <BLINK> and Avoid Flickering on the Page
Do not use the <BLINK> tag. When possible, avoid images, marquees, animations, scripts, applets or plug-ins that flash, flicker or blink. Blinking images with frequencies higher than 2 Hz and lower than 59 Hz (2-59 times per second) may cause seizures for individuals with photosensitive epilepsy. (Reference: W3C: 7.1; DOJ, Section 508: j)