Part 2
Specific provisions
Section 5
32. Enforcement of sentences of imprisonment
General provisions
2. The sentences of imprisonment passed by the International Criminal Court shall be enforced directly. Sentences passed by the International Criminal Court may not be modified. In the light of instructions from the International Criminal Court, enforcement shall be subject to the relevant provisions of Austrian law on the understanding that the conditions of detention correspond to those under which persons convicted of similar crimes are held in Austria.
Non-modification of sentence by State
Conditions of imprisonment / detention - international treaty standards
EDIT.