Greetings!
         Since I started this thread I would like to make an observation on
where it has gone. I was looking for a way for people to kill colonies
without ruining the honey and combs, ie., if a colony has mites so bad that
they won't survive (or if the temper indicates they may have African
parentage...). I think one of the best tips was to shake the bees off the
combs into soapy water. If one had several hives to do, one could probably
use a trash can or some other large container.

         The talk of sterilizing AFB hives is a different matter
altogether. I think most beekeepers have come to the conclusion that it is
not cost effective to salvage AFB infected equipment, except the heavy wood
like the supers, covers and bottoms. These can be quickly sterilized with a
propane torch and repainted. I would just burn up the frames and combs. Now
the hard plastic foundation is another matter. One shouldn't burn this and
it could very likely be salvaged by removing it from frame, scraping off
the comb, and soaking the plastic in a chlorine solution.  I haven't done
this.

         I would avoid chlorine gas at all costs. Beekeepers have died from
gases, including EDB (ethylene dibromide) which used to be used for
fumigating combs and killing bees. I don't think cyanogas is readily
available nor is it approved for use on bee hives (in the US).

Peter Borst