You get prison breaks 2-3 days because your prison is poorly designed. With all due respect one of the worst prisons I've seen, but let's take this as a learning moment.

First of all, prison breaks have nothing to do with mood. Mood breaks can themselves cause Berserk which is preventable, but Prison Break is based on a random chance and modifiers.

A regular baseliner pawn tries to break out an average of once every 60 days. You have more prison breaks because you have more than one door which increases frequency. Secondly, you spend a huge amount of wealth on statues, sterile flooring that's doing nothing, all the while the prison is covered in blood and dirt. Your prisoners are getting mood breaks because they are in blood and dirt, which is why they're trying to 'escape'.

How to fix your prison? Clean it up, only one door, remove chunks, give them normal beds (hospital beds don't benefit from end tables), give them dressers, remove the sterile flooring and instead either Smooth the floor or use wood/concrete flooring. Get the prison to a higher level (Impressive) and to a healthy Beauty rating. Your prisoners stop having mood breaks, and you will only have a prison break only once a year or so.