Additional info about integrating BAS and fire/life safety systems
The presenters from the webcast about “Integration: BAS and Fire/Life Safety” respond to questions not addressed during the live presentation.
The webcast presenters addressed several questions posed during the presentation about integrating building automation systems (BAS) and fire/life safety systems. Questions not addressed during the presentation were answered by:
- Erik Anderson, PE, Manager, Koffel Associates, Columbia, Md.
- Wayne D. Moore, PE, CFPS, SET, FSFPE, F.NSPE, Principal and Vice President, Hughes Associates | RJA Group, Warwick, R.I.
Question: How can the reliability of the fire alarm system be maintained while mixing data with other non-emergency inputs?
Answer: In reality the fire alarm system reliability is unaffected by other integrated systems when using the BACnet protocol due to the required use of the gateway interface. The gateway keeps the other signals on the network form affecting the fire alarm system.
Question: Building automation systems are more and more residing on an owner's IT network. If a BACnet gateway is used to interface to the fire alarm system, instead of hardwired connections, this device would reside on the owner's network which is likely not UL listed. Have you come across this concern?
Answer: The BACnet gateway itself is required to be listed, but not the system. So the fire alarm system devices or zones would be connected to the listed gateway and then the other side of the gateway would be connected to the network allowing the objects to be transmitted to the BAS, for example. Once again we are still required to use the listed gateway as the interface but the balance of the non-fire alarm system equipment does not need to be listed for fire alarm use. Having said that there are changes proposed to NFPA 72-2016 that would allow direct connection to the Ethernet or a network under certain conditions. These proposed changes have not yet been officially adopted.
Question: Do you recommend integrating the building fire alarm system and the BAS in an office building that undergo tenant fit-outs on a continuous basis?
Answer: With any system design in any building or occupancy planning is imperative. Knowing beforehand that the occupancy is to be offices and knowing that tenant fit-out occur on a regular basis, it is incumbent on the original system designer to include system changes and expansion in his or her design. Just because frequent changes to a system are expected does not preclude integrating all of the systems. It does require more coordination and provided that happens the systems should remain reliable.
Question: Does OEO override designated and alternate recall operation?
Answer: No, just the opposite. All recall features (elevator lobby smoke detectors for example) would input to the OEO controller and it would relinquish OEO or those floors in recall.
Question: How would elevator shunt trip for a sprinkled hoistway or elevator equipment room operation work into the OEO sequence of operation?
Answer: As stated previously, when these types of operations occur during or prior to OEO, these operations would take priority over the OEO and all OEO for the affected elevators would cease and all signs and voice messages would revert to “Do Not Use The Elevators, Use The Stairs” operation.
Question: How would the use of BACnet interface to emergency control systems, requiring supervision of control wiring, address this code requirement?
Answer: NFPA 72-2013 (and previous editions) require supervision to within 3 ft of the controlling device or no supervision if the device operation is fail-safe, meaning if the connection to the device is severed, the emergency device operates as required. The gateway could be determined as the connection to the controlling device and as long as that was within 3 ft of the controller it would be considered code-compliant. This is unlikely to happen and other design considerations will need to be considered to ensure that the performance of the emergency control system is code compliant. Given the many types of configurations, there can be no one definitive answer to the problem until the actual field condition is evaluated.