Class A Fire Alarm

[Cosecantenabler]

Concerning Class A fire alarm separation of pathway in the bottom of an elevator shaft.
can the in and out conductors be in the same conduit to a smoke and heat detector? I cant find anything about it under hoist ways, so is it considered a room of 1000 square feet or less? Feeding
a single device? Welcome to comments.

 

[ron]

I think the 2016 NFPA 72 change the language allowing multiple devices in 12.3.8.1(3) but the smoke and heats are part of emergency control functions so I think you are out of luck

12.3.8* Class A and Class X Pathway Separation.
12.3.8.1 The outgoing and return (redundant) circuit conductors shall be permitted in the same cable assembly (i.e., multi-conductor cable), enclosure, or raceway only under the following conditions:
(1) For a distance not to exceed 10 ft. where the outgoing and return conductors enter or exit the initiating device, notification appliances, or control unit enclosures.
(2) Single drops installed in the raceway to individual devices or appliances.
(3)* In a single room not exceeding 1000 sq' in area, a drop installed in the raceway to multiple devices or appliances that does not include any emergency control function devices.

 

[gadfly56]

I think the 2016 NFPA 72 change the language allowing multiple devices in 12.3.8.1(3) but the smoke and heats are part of emergency control functions so I think you are out of luck

12.3.8* Class A and Class X Pathway Separation.
12.3.8.1 The outgoing and return (redundant) circuit conductors shall be permitted in the same cable assembly (i.e., multi-conductor cable), enclosure, or raceway only under the following conditions:
(1) For a distance not to exceed 10 ft. where the outgoing and return conductors enter or exit the initiating device, notification appliances, or control unit enclosures.
(2) Single drops installed in the raceway to individual devices or appliances.
(3)* In a single room not exceeding 1000 sq' in area, a drop installed in the raceway to multiple devices or appliances that does not include any emergency control function devices.

I think "emergency control function" is intended for relays and control modules. Even though the heat and smoke (which, by the way you should not have a smoke in the pit) are associated via software with an emergency control function, they are still initiating devices. They do not directly perform any control function.