Duct Smoke in Supply for Stair Pressurization?

For a smoke control stair pressurization system designed in accordance with IBC 909 and IMC 513, does the code require a duct smoke detector on the supply fan?

Does the installation of a smoke damper at the stairway boundary factor into this requirement? (i.e. IBC 717.3.3.2 requires a detector within 5 feet of a smoke damper). Normally this motorized smoke damper is closed and then automatically opens upon activation of a specific fire alarm signal.

NFPA 92 6.4.6.2 does require a duct detector on the stair pressurization supply fan; however, I'm unaware of a similar requirement in IBC/IMC. NFPA's intent is to detect smoke on the air supply and shut down the unit before smoke compromises the stairway.

For elevator hoistways that require smoke control, IBC 909.21.4.2 states to provide a detector. I would have expected a general statement in IBC 909.12 with the same intention as NFPA 92; however, I do not see a similar requirement in the IBC/IMC for stairways.

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