Sentence 3.2.4.18.(9) in combination with Sentence 3.2.4.18.(10) require separate audible signal circuits for dwelling units.
It allows the designer the option to wire the audible signal devices in a dwelling unit on an individual circuit that serves each suite only or to wire the audible signal devices in a common circuit that serves the dwelling units within the floor area and is separate from the circuit that serves the audible devices outside the dwelling unit. Compliance with either of the above two options would meet the intent of a separate circuit required in Sentence 3.2.4.18.(12).