760.56 (D) Mass Notification panels/ fire alarm wiring

[Cyberpett]

New Projects being installed under the 2005 code with the new Fire Alarm/Mass Notification systems (mostly governement required), Have speakers with a dual purpose. The speaker serves the function of fire alarm audible appliance device ( via Siren driver built into Audio components). And either pre-recorded automated voice messages or live audio voice announcements. (whew!)
The NEC 760.56D Prohibits the installation of Fire alarm power limited cables
in the same conduit as audio system circuits (iether 70.7 v or 24.0 v nom) as described in 640.9 (basically anything load or output side of an audio amplifier) Since I deemed the mass notification system to meet the definition of the Audio circuits as described in 640.9 it would prohibit any speaker cabling from being run in the same conduit. And conduit has been specified with fplCI cable as required installation method for both systems.

Is there any way to be able to combine these cables in the same conduit?

What would the impact be to reclassify the Fire alarm cable as Class 1 circuits since there already in conduit anyway).
Would not the requirement to separate the cables still be in effect? (since accourding to my NFPA handbook the reason for this requirement was the properties of Audio circuits will significantly damage fire alarm systems in the case of a short)
By the way, both Fire and Mass Notification have requirement for CI cable in the spec.

 

[Edgreer]

Voice EVAC

Voice EVAC

Okay! Mass EVAC is not the same in one sense. The speaker wire and the horn/strobe wiring can be in the same conduit and is is normally installed that way we install a PL shielded cable (FPL or FPLP) for the speaker circuit and then pull either 12 or 14 ga THHN for the Horn/Strobe circuit 760.56(D) is talking abut aux sound systems or backgtround systems which should never be in FA system conduit.

 

[orgonfire]

Edgeer is right. Normally, fire evac systems involves a voice control panel triggered by an FACP. Voice signals are run in a separate shielded circuit from strobe circuits, all in the same conduit. Of course, its all power limited..