Tom Elliott asked what temperature is needed to kill AFB spores.
 
I am currently part of a team looking to see if we can sterilise bee boxes in high temperature timber drying kilns.  The lab work has shown that it is far easier to kill the AFB spores in a wet solution than in a dry condition.
 
Hopefully, our work will be completed by the middle of this year and I will be able to give you an answer.
 
As for the scorching, I know a beekeeper who had AFB and destroyed al the frames but kept the boxes, lids and bottom boards if they were in good condition.  He scorched inside and out with a blow torch and then re-painted the boxes.  He has not (scorching was done about 13 years ago) to date had any re-infection.
 
It was a lot of work but the beekeeper concerned was retired and had time to spare.  The cost, in material terms, was far less than replacing with new equipment.
 
Trevor Weatherhead
AUSTRALIA