There are post on BM that explain Double screen Bottom Boards with oil or water pan and this does a wonderful job of controlling SHB. I went through some hives this AM and found 3-4 SHB in a hive that had a leak in the oil pan and it ran dry. I also put every thing in a deep freeze for 2-3 days, honey to be extracted and this is including any frames with drawn comb that are to be stored, then I wrap them in a garbage bag, and tape the end shut. There will be other options that works for other BEEKs, try to figure out what works best for your situation, good luck.