. >> sergeant rudy carmella supervises cellblock 5, one of the oldest operating prison structures in the united states. >> to walk up to a cell, to look -- to see what is going on, you have to sometimes look inside. so it puts us at close proximity to whomever, whatever is in here. sometimes it could be dangerous. he could spear you through these holes, and they make the antiquated type out of a newspaper with a blade at the end of it. very simply it could be done, stab you in the face or the side and so forth. >> officers in newer prisons avoid the hazard of getting close to inmate doors. >> the newer prisons are now all automated with button control. one officer could actually control up to 100, 200 cell doors at one given time. here in this unit, every individual door has to be opened by key. every single door. >> the doors must be locked and unlocked several times a day as inmates are released to the yard. to do so, two staff officers snake their way through narrow passageways and the central corridor, 160 yards long. in the process, they can find themselves surrounded by hundred