From the 2022 NYC Building Code
1705.18 Testing for smoke control Special Inspection.
Testing of smoke control systems shall be witnessed in its entirety by a special inspector in accordance with Sections 1705.18.1and 909.
Exception: Post-fire smoke purge systems that are not required to function as a smoke control system shall be permitted to be inspected pursuant to the special inspection requirements of Section 1705.21.
1705.18.1 Testing scope. The test scope shall be as follows:
During erection of ductwork and prior to concealment for the purposes of leakage testing and recording of device location.
Prior to occupancy and after sufficient completion for the purposes of pressure difference testing, flow measurements and detection and control verification.