(a) Installation of ducts which pass through construction required to have a fire-resistance rating shall comply with the requirements of subchapter thirteen, provided that, notwithstanding the provisions of subchapter thirteen or reference standard RS 13-1, noncombustible ducts which pass through construction required to have a fire-resistance rating of one hour must be provided with fire dampers unless:
(1) The building is classified in occupancy group C, E, or H-2; and
(2) Complete sprinkler protection is provided for the floor in accordance with subchapter seventeen; or
(3) The openings for the ventilation ducts do not exceed three square feet in area; or
(4) The duct is protected on both sides of the partition for a distance equal to the maximum duct dimension by a sleeve affording one hour fire separation for such horizontal distance.
(b) Noncombustible pipes and conduits. Noncombustible pipes and conduits may pass through construction required to have a fire-resistance rating provided that the space between the pipe or conduit and its sleeve or opening does not exceed one-half inch and is completely packed with mineral wool or equivalent noncombustible material and is closed off by close-fitting metal escutcheons on both sides of the construction; and provided further that the aggregate net area of such openings does not exceed twenty-five square inches in any one hundred square feet of wall or floor area (excluding the areas of openings for sleeves which are firestopped in conformance with this section and section 27-345).
(c) Openings for passage of pipe and ducts whose aggregate net area exceeds twenty-five square inches in any one hundred square feet of wall or floor area (excluding opening for sleeves which are firestopped in conformance with this section and section 27-345) may pierce constructions required to have a fire-resistance rating only when the type of construction to be used has been tested with such types of facilities installed in place and the proportionate area of openings of such facilities to be installed in the construction does not exceed the proportionate area of openings in the assembly tested, and provided no opening is larger than that in the assembly tested. Protection of such openings shall be the same as provided in the test. All openings through hollow fire rated construction shall be sleeved with sheet metal least No. 14 U.S. std. gage thick.
(d) The installation and proper functioning of required fire dampers shall be subject to the controlled inspection requirements of section 27-132 of this code, except that it shall not be required that the architect or engineer be in the employ of the owner.