According to 19 2 2 2 4 of the 2012.
Stairwell doors locked.
An nfpa code allows stair doors to be locked from the stairway side if the locks will release upon fire alarm activation nfpa 101 7 2 1 5 7 2.
Stair doors providing reentry must be equipped with a fail safe product and since fail safe electric strikes can t be used on fire doors a fail safe lock or fail safe exit device trim is.
Thus as with an external door a card reader can be installed on the stairwell side of the door as long as it will be overridden when a fire alarm sounds.
Commercial building stairwell doors often are locked on the stair side to prevent unauthorized entry from the stairwells into tenant spaces.
The term stairwell reentry refers to the code requirements which allow a building occupant to leave a stairwell during a fire emergency and find another exit.
For doors that are locked on the stair side the ibc requires the locks to be capable of being unlocked simultaneously without unlatching upon a signal from the fire command center if present or a signal by emergency personnel from a single location inside the main entrance to the building.
Although the ibc would require just about all stairwell doors to be able to be unlocked remotely nfpa 101 has some exceptions.
Selected reentry allows some doors to be mechanically locked and some doors must allow reentry.