  If possible, use those ones on only one hive, and monitor carefully. The general wisdom here is monitor closely for one year, at the end of that year you can relax some, but at the end of year two you can consider the hive as clean as any other hive.  It's probably most likely you will not get an AFB infection but if the worst happens and you do, please come back to the thread and let's know, it will be useful info. You could also come back and say, if you didn't get AFB.  I 