To limit the probability that persons in sleeping rooms will not be promptly notified of a fire in other parts of the dwelling unit or within their room, which could lead to delays in evacuation or moving to a safe place, which could lead to harm to persons.
To limit the probability that a fire involving a floor level will not be detected, which could lead to persons on that floor level or on another floor level not being promptly notified of the fire, which could lead to delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons.