  The final state interactions of pions in decays $K^\pm\to\pi^\pm\pi^0\pi^0$
are considered using the methods of quantum mechanics. We show how to
incorporate the electromagnetic effects in the amplitudes of these decays and
to work out the relevant expressions valid above and below the two charged
pions production threshold $M_c=2m$. The electromagnetic corrections are given
as evaluated in a potential model.
