Correct way to make someone a mod of a specific forum board?
 

What is the correct way to make someone a mod of a specific forum board?

It seems when I use forum manager and select a new mod for a board it gives them permissions beyond the specific board to delete threads elsewhere, etc.. I even heard from a new board mod that they were getting reported post email notifications.

I just want them to be a mod on their board. Not sure what I am doing wrong.