http://www.hmprisonservice.gov.uk/careersandjobs/

I work in a similar work enviroment within police custody it is a real team job and you have to keep your wits about you. Some proper wrong uns in this world and you would be dealing with every kind of them on a daily basis..fights/self harm/suicide attempts , dirty protesters if things like this float the boat then its the job for you.

The assesment day is a basic muliple choice test, maths, problem solving etc, and then a face to face interview, questions about yourself, just to see your outlook on certain aspects and to gather a liitle insight about you.