Re: CI cable for smoke detectors
CI Cable is a very special cable with a 2-hour fire rating. Most fire alarm system devices do not require CI cable.
CI cable is only required if mandated by the building dept. which would steer you toward NFPA 72, then to NFPA 70.
Generally it is used for notification circuits in a high rise building where selective evacuation is required which then requires circuit survivability.
That is the minimum, you may do it in others places if you like.