Equally my canteen has a staff entrance to the kitchen and it's marked as staff only. they'll be beaten if they're caught anywhere near there (there's also solitary lockdown doors if there should be an attempted escape). Prisoners can't even get near the staff doors on the entrance/exit to my prison because of staff only zones - i.e.

What's wrong with staff doors? In all my most recent prisons, chefs are able to come and go through my prison with ease. Of course, letting more staff types have access to keys raises risks of its own - prisoners might be more inclined to attack staff if they think they can get their key and squirrel it away before they egt put in lockdown, for example - but that's one of those risk-reward deals that should be open to the player. If you're not comfortable with certain types of staff having security access, you can keep them in the normal state state while allowing the ones you DO want to have the run of the system - workers might be too risky given their sheer numbers and frequency of opening the front gates making good escape attempt opprotuneties, but you could let doctors have access since their ability to get quickly to a location can literily be the difference between life and death. So what about an option on the staff screen to allow certain types of staff to have keys to open jail doors on their own, like a little checkbox or drop-down menu next to each staff type entry? That way they're no longer beholden to guards to clear the path for them and you can keep supply chains running smoothly. Depending on how thoroughly you've developed your security measures, however, that also means more checkpoints that staff have to be walked through by guards, which can cause some major back-ups that could lead to rather nasty consequences (chef can't deliver ingredients in time to feed all prisoners, super-hungry prisoners start making trouble, others join in, soon it's a riot depending on how bad things have gotten). The larger your prison gets and the more developed it becomes, the more hectic things tend to get: more prisoners means you need more chefs to prepare food, more workers to build facilities and handle workshop deliveries, more doctors to deal with injuries.

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