Protocol with reps and Trade Shows

I am curious to know what the protocol is with having multiple sales
reps and doing shows. Meaning, if I have a rep in Pennsylvania and
another rep doing a trade show for me, what happens when buyers from
Pa. want to write orders? Since Pa. is one reps territory, are they
allowed to tell you that another rep cannot place orders for those
stores at a trade show? Because my business is growing, I am faced
with this dilemma for the first time. I am adding reps all around,
and certain reps do certain shows. Do they have the right to claim
their territory in such a circumstance? i am not sure how to go
about this and was wondering how others have handled this situation.
I would love any advice.

Laura J. Designs