[LE] Setting NPC to use area effect shout/spell only if there are no friends/allies in the area.

[RandomBoar]

I created a shout that uses a powerful area effect spell that staggers and knocks down nearby characters and gave it to a follower NPC, now he sends me flying with the enemies if I happen to be close to him when he uses this shout. Is there a way to make him use that shout only if he's surrounded by enemies and there's nobody else inside of the spell area?