607.5.2.2 Public corridors.
MC § 607.5.2.2
A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a public corridor wall constructed as a fire barrier. Exceptions: 1. Smoke dampers are not required where the building is equipped throughout with an approved smoke control system in accordance with Section 909 of the New York City Building Code, and smoke dampers are not necessary for the operation and control of the system.
2.Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness and there are no openings serving the corridor.
3.Smoke dampers are not required in corridor penetrations in Group R-2 buildings and public corridors serving R-2 spaces in mixed use buildings.
4.Smoke dampers shall not be required in ducts where the air continues to move and the air-handling system installed is arranged to prevent recirculation of exhaust or return air under fire emergency conditions or loss of normal power by provision of standby power in accordance with Chapter 27 of the New York City Building Code.
