from SoCal Referees:
7 A ball carrier may hand off an opponent. Can 10.4 (e) apply?
The attacking ball carrier is allowed to fend with an open hand to the chest or face. Is it possible to give a guideline to when a fend becomes dangerous and how a referee can identify and judge that action?
The law is very clear on this:
A ball carrier may hand-off an opponent and is clearly defined:
Hand-off: An action taken by a ball carrier to fend off an opponent by using the palm of the hand.
Referees that penalize hand-offs to the head are making law up as they go along and should stop doing so. You are illegally removing a key skill from the game.
There is a very clear and easy distinction:
The hand that goes to the face and holds the opponent at arms length or pushes them away is NOT illegal.
Please Note *****
When delivered with deliberate impact (especially with the butt of hand), striking the face is illegal.