You don't want SuperMax prisoners in the general population.It is a good idea to assign a prisoner with both the volatile and deadly (or their extreme version) traits to SuperMax, as they can kick off for no reason and cause a lot of casualties when guards try to subdue them.

SuperMax should be used for prisoners that can cause a lot of casualties or you want to punish hard.Gang Members, Volatile, Deadly, Extremely Deadly, Extremely Volatile, and Legendary are recommended here. The player could also decide to keep the prisoners on permanent lockdown with armed guards nearby to ensure that they won't cause trouble outside their cells. It is common for SuperMax prisoners to be locked up nearly the whole day and only be let out for one hour of yard time and a few moments of eating during the day. SuperMax is assigned to the most dangerous of prisoners that cannot be allowed in the general population, because of their highly dangerous traits. As of the Cleared for Transfer update, this is a security class that is set automatically and can be received from intake.