Is there a way to create a validation on the supplier address ?

We have a need to create a validation on the address entered when creating a supplier.

Is there a way to validate what is entered by the user before clicking save ?

We need to make sure that no PO Box is entered on the line address 1 of the supplier profile.

The reason why we need to create a validation or verification is that the bank is refusing payment to these PO boxes.

Thank you.

Mark H.