A. Before the 2013 edition of NFPA 72, the rule regarding emergency control functions made more sense. Lucky for you, your state is currently using the 2010 edition which, in section 21.2.4, states: “A listed relay or other listed appliance connected to the fire alarm system used to initiate control of protected premises emergency control functions shall be located within 3 ft. of the controlled circuit or appliance.” Because you are bringing the “controlled circuit” to the lobby smoke detectors, you are in compliance.
In the 2013 edition of NFPA 72, two new terms were invented. The new 2013 wording for section 21.2.4 was changed to read: “Emergency control function interface devices shall be located within 3 ft. of the component controlling the emergency control function.”
I think they made a mistake when omitting the “controlled circuit” wording. Without this wording, it seems that only digital signals or addressable relay modules (on digital circuits) may now be used, and relay-bases cannot since the detector is seldom going to be located within three feet of the “Emergency Control Function Interface Device.” This omission might be a typo since a diagram in the 2013 Annex still shows a relay-based smoke detector being used for elevator recall. It’s doubtful that relay-based detectors are not going to be considered to be an “emergency control function interface device” when your state adopts the 2013 edition.
Here are two new terms from the 2013 edition of NFPA 72 affecting the three-foot rule:
3.3.90 Emergency Control Function Interface Device — a listed fire alarm or signaling system component that directly interfaces with the system that operates the emergency control function.
220.127.116.11.2 Emergency Control Function Interface — the interface between the fire alarm system emergency control function interface device and the component controlling the emergency control function.