Article 9 Noise Control in Multiple Dwellings

Interior walls, partitions, floor-ceiling constructions, and mechanical equipment in spaces or buildings of occupancy group J-2 shall be designed and constructed in accordance with the requirements of this subchapter, to provide minimum protection for each dwelling unit from extraneous noises emanating from other dwelling units and from mechanical equipment. In addition, airborne sound from exterior mechanical equipment of buildings in any occupancy group shall conform to the requirements of this subchapter.

(a) Field testing. Where conditions indicate that the installed construction or equipment does not meet the noise control prescribed in this subchapter, measurements shall be taken to determine conformance or non-conformance. For conformance with this subchapter, the results of such measurements shall not fail by more than two db to meet the requirements in any octave band, or by more than two points to meet any STC or INR requirements.

(b) Materials or assemblies of materials utilized to meet noise control requirements shall comply with load bearing, fire protection or other applicable requirements of this code for walls, partitions and floor-ceiling constructions.

(a) Airborne noise. (1) Walls, partitions, and floor-ceiling constructions separating dwelling units from each other or from public halls, corridors, or stairs shall have a minimum sound transmission class (STC) rating of forty-five for airborne noise. This requirement shall not apply to dwelling unit entrance doors. However, such doors shall fit closely and not be undercut. For permits issued after January first, nineteen hundred seventy-two, the STC required shall be fifty for airborne noise. For permits issued after April thirtieth, nineteen hundred seventy-three, dwelling unit entrance doors shall have a minimum STC of thirty-five.

(2) STC ratings shall be obtained by tests conducted in accordance with the procedures of reference standard RS 12-2 except as provided in paragraph three of this subdivision.

(3) The STC ratings of construction assemblies as listed in reference standard RS 12-2 may be used to determine conformance with the requirements of paragraph one of this subdivision and with any other section that requires a specific STC rating.

(4) Penetrations or openings in walls, partitions, or floors for pipe sleeves, medicine cabinets, hampers, electric devices, or similar items shall be packed, sealed, lined, back-plastered, or otherwise isolated by sufficient mass to maintain the required STC ratings.

(5) Where grilles, registers, or diffusers in one dwelling unit are connected by duct-work with grilles, registers, or diffusers in another dwelling unit, and where such connecting duct is less than seven feet long, it shall be lined with duct lining; otherwise, an approved sound attenuating device shall be installed therein. Duct lining shall conform to the requirements of subchapter thirteen of this chapter.

(b) Structure-borne noise. (1) Floor-ceiling constructions separating dwelling units from each other or from public halls or corridors shall have a minimum impact noise rating (INR) of zero.

(2) Such INR shall be obtained by tests conducted in accordance with the procedure of reference standard RS 12-3 except as provided in paragraph three of this subdivision.

(3) The INR of floor-ceiling constructions listed in reference standard RS 12-3 shall be used to determine conformance with the requirements of paragraph one of this subdivision and with any other paragraph that requires a specific INR. Constructions shall be designed and installed to avoid short circuiting the isolation devices that are incorporated into the constructions.

(4) This subdivision shall apply only to construction pursuant to permits issued after the thirty-first day of December, nineteen hundred seventy-six.