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Current NFPA Requirements 1

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mauricestoker

Mechanical
Oct 3, 2007
533
I am working on the upgrade of a building automation system (BAS) at the same time as design for an air handling unit (AHU) for an existing hospital. The AHU supports zones on six floors, as well as interstitials. Each interstitial is a single smoke zone. During site investigation, I noticed that a construction contractor had inadvertently demolished an interstital supply and associated SCD. The demolition did not trigger any alarm or trouble to the FACP, no FSCS exists, and no audible alarm was sounded at the BAS. Error message printout did show the date and time when the pneumatic control tube was plugged, which I assume was when demolition occurred.

For the AHU under design, existing control sequence is when products of combustion are sensed by the interstitial returm duct smoke detector, the detector reports to the FACP, which automatically initiates a smoke control program through the BAS. The BAS will close all interstitial supply and return SCD's, energize the interstitial purge fans, and AHU associated with the return will have return duct close and relief damper go full open.

My question, after being long-winded, is: should the FACP or a FSCS receive a trouble alarm or notification when a SCD is demolished (duct smoke detector may still be intact) or is reporting to the BAS (no audible alarm, not continually manned) satisfactory by current NFPA? My concern is that if the return SCD does not close or does not exist, the products of combustion will then be picked up by the AHU, causing it to shutdown, and lead to horizontal evacuation on 6 floors. Additionally, I have noted that the BAS components are not FM/UL listed; if part of the fire/smoke protection program, would all non-listed components need to be replaced?
 
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I think the answer is the smoke detector in th duct detector is the only thing that is monitored.

If it senses somthing, the head is removed or the power wires to the detector itself ar cut, then the fire alarm panel hould get a signal.

the ahu is not monitored typicaly by the fire alarm panel


does this answer your question???
 
Thank you very much. Being an ME and not FPE, I may be too paranoid about the issue. When it comes to safety, I have a paranoia streak and like to consult with subject field experts (an FPE, not an ME). What really had me hung up was NFPA 92A (6.4.3.7.1) where an FSCS is to be provided for all smoke control systems. The thread on flow switch activating smoke control zone, and being coincidental with that zone (6.4.5.1.1.4) and the interstital zone not being sprinklered made me think a bit too much out of my field.
 
mauricestoker

If life safety is making weak I think that as a Mechanical Eng. You should at least try to go for some NICET certification. It will take some of that paranoia from you. Please give it a shot. If you need help just ask.
 
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