rules for eyeshields?

[razorr]

i know that the new rule for ncaa division I and II are that you cannot wear a visor at all unless you have a doctors note, and on top of that you cannot wear any type of tinted or mirrored visor it must be completely clear! i would like to know does anyone have information on if that applys to NAIA and division III? and why the heck would they make a rule like this after all these years of it not being an issue? is there saftey hassards to this object on the helmet that is supposed to protect the eye, (hits, sunglares, etc). please someone give me some answers