Hello Lennard,
Back in the 20's, 30's,  and 40's, boiling in  a strong solution of NaOH was
the "way"
used by many beekeepers to kill AFB spores.  Generally, the only parts
"decontaminated" by this means were the hive bodies and bottom board.  Frames,
inner covers, and  excluders were too flimsy to stand the effect of the NaOH,
and hence were rarely subjected to this harsh treatment.

The major problem is danger to YOURSELF and of course the finding of a
suitable place to dispose of the used NaOH.  If you are NOT a chemist, sodium
hydroxide is
dangerous to handle, and HOT "lye" is EXTREMELY DANGEROUS to you.

I have used this method, back in the 30's, in the woods with a 55 gallon drum
heated
with a wood fire under it.  I was young and foolish then.

I would be strongly opposed to an amateur using NaOH today, and legal
disposal of
the used NaOH would be almost impossible.

What state are you in?  Maryland and North Carolina can decontaminate bee
equipment with ethylene oxide, and Massachusetts uses cobalt irradiation.

Hope I have helped.

George Imirie
EAS Master Beekeeper
Starting my 70th year of beekeeping in Maryland