If you are not employed there, our statutue uses slghtly different language then many other states in that it says:
"(M) A permit issued pursuant to this section does not authorize a permit holder to carry a concealable weapon into a:
(2) detention facility, prison, or jail or any other correctional facility or office"
The key word in the above, IMHO would be the word INTO whereas many other states will say "on the premisis". As an employee, however, that may be very different as I remember several cases I read on that same topic wherein the employees' vehicles were searched, the hand guns found and ceased and the employees fired - all within the law so definately cheeck first if that is the case.