Where Are All the Hard Hats?

A very important issue in football is safety. The NFL has set up rules and regulations to try and protect the players on the field from receiving serious injuries while in the game. However, no one seems to think about the guys running around on the field with only flags and ball caps. Thats right the officials. They are a part of the game as much as each player and are at risk to suffer the same blows that could be received by any player on the field. With officials being accidentally tackled, ran over, and hit, I'd imagine the least they could wear is a hard hat. I mean, whats to stop them from receiving a concussion from a hard blow to the head. This rule should be set up not only on a professional level but a collegiate level as well.