Mortise Exit Door Devices (Panic Hardware) The terms "crash bar", "panic bar", and "exit device" all mean the same thing. Exit devices are used on doors in the path of egress in buildings built to accomodate numbers of people. Facilities like schools, hospitals, goverment buildings and large residential buildings all use them. Fire rated exit devices are used on fire rated doors. Most interior doors that require exit devices, especially stairwell doors, are fire rated.