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Notification appliances outside the evacuation signaling zone

Question asked by shirazmacuff on Dec 29, 2017
Latest reply on Jan 2, 2018 by cdafd

Hi all,

I'm stuck on this problem. Hopefully some one can help

I'm working on building that requires partial evac.

 

I have a situation where one SLC serving booster power supplies on several floors are enclosed in 2 hour rated rooms. The boosters are serving all NACs on each floor. The SLC is being design with short circuit tolerance. 

 

1) Would the 2 hour fire rated rooms satisfy 23.10.2 below? It seems that it exceeds level 1 survivability A.23.10.2(1).  

2) will short-circuit fault-tolerant and  2 hour fire rated rooms satisfy the 23.10.2 requirement without routing separate NACs or using class A (separated feed and return routed) SLC?

 

Thanks all for your help

 

I hope its okay to post the references

 

Reference [2]:

NFPA 2010

 

23.10.2* Fire alarm systems used for partial evacuation and relocation shall be designed and installed such that attack by fire within an evacuation signaling zone shall not impair control and operation of the notification appliances outside the evacuation signaling zone. Performance features provided to ensure survivability shall be described and technical justification provided in the documentation submitted to the authority having jurisdiction with the evaluation required in 23.4.3.1.

 

A.23.10.2 One or more of the following means might be considered acceptable to provide a level of survivability consistent with the intent of this requirement:

(1) Installing a fire alarm system in a fully sprinklered building in accordance with NFPA 13, Standard for the Installation of Sprinkler Systems

(2) Routing notification appliance circuits separately

(3) Using short-circuit fault-tolerant signaling line circuits for controlling evacuation signals

 

The requirement for notification appliances to operate in those evacuation signaling zones that are not attacked by fire will also require that circuits and equipment that are common to more than one evacuation signaling zone be designed and installed such that the fire will not disable them.

For instance, a signaling line circuit used to control notification appliances in multiple evacuation signaling zones should be properly designed and installed so that one fire would not impair the signaling line circuit, rendering the notification appliances serving more than one evacuation signaling zone inoperative.

Power supply requirements of Chapter 10 apply to these systems. The secondary power supply requirements of that chapter meet the intent of these survivability requirements.

 

 

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