Speed on Animated Gifs

Guys/Girls,

Does anyone know if there is an acceptable "time" between frames on
Animated Gifs?  I have one that needs to go on a site that I develop,
but I don't want to break 3.7.1 and 3.7.2 ("Flickering, flashing and
blinking should be avoided or at least
limited.").

I heard somewhere that there was an acceptable amount of time, but I
can't remember exactly what it is.

Thanks

James