Section 27-768
§ 27-768 Requirements. 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.
Section 27-769
§ 27-769 Acoustical isolation of dwelling units. (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.
Section 27-770
§ 27-770 Noise control of mechanical equipment. (a) Minimum airborne
noise insulation requirements.
(1) BOILER ROOMS. Boiler rooms adjoining dwelling spaces, either
vertically or horizontally, shall be separated therefrom by
floor-ceiling or partition constructions having a minimum STC rating of
fifty.
(2) MECHANICAL EQUIPMENT SPACES. Spaces or shafts containing air
conditioning, refrigeration, or ventilating equipment, elevator
machinery, or other mechanical equipment shall be separated both
vertically and horizontally from dwelling units by constructions that
will provide a minimum STC rating of fifty. Spaces or shafts containing
equipment totaling more than seventy-five rated h.p. shall not be
located vertically or horizontally adjacent to dwelling units unless the
total sound power level output of all the equipment in the space or
shaft is certified not to exceed the maximum sound power levels of table
12-3 in any octave band. Such sound power level ratings shall be
obtained by tests conducted in accordance with the procedures of
reference standard RS 12-5.
a. Ventilating openings into mechanical equipment spaces. Ventilating
openings into boiler rooms and other mechanical equipment spaces shall
not be located in yards or courts where there are windows opening from
living quarters, unless such ventilating openings are provided with
sound attenuating devices if needed to limit noise transmission to NC-40
(noise criterion) levels in the exposed dwelling units. For permits
issued after January first, nineteen hundred seventy-two, the
permissible noise levels shall not exceed NC-35.
b. Noise criteria requirements. Noise criteria requirements prescribed
in this subchapter shall be in accordance with reference standard RS
12-4.
Table 12-3 Maximum Sound Power Levels Permitted in Mechanical Spaces or
Shafts Adjoining Dwelling Spaces
========================================================================
Max. Sound Power
Level db(a)
-------------------------------------
Octave Bands, c.p.s. db re db re
Mid-Frequency 10(-13) Watts 10(-12) Watts
------------------------------------------------------------------------
63 101 91
125 101 91
250 103 93
500 105 95
1000 102 92
2000 101 91
4000 98 88
8000 96 86
========================================================================
Notes:
a. The maximum sound power levels shall be reduced five db in any
octave band where the equipment data indicate pure tone generation. The
presence of pure tones may be determined by means of one-third octave
band analysis. The criterion for a significant pure-tone component shall
be an audible pure-tone sound together with an increase of the sound
pressure level in the corresponding one-third octave band above the mean
of the two adjacent one-third of at least:
Center frequency of
one-third octave
band.......... 40/125 160/250 215/500 630/1,000 1,000/10,000
Increase in sound
pressure level
(db)............ 6 4 3 2 1 1/2
------------------------------------------------------------------------
b. For permits issued after January first, nineteen hundred
seventy-two, the maximum sound power levels shall be changed as follows:
========================================================================
Octave Bands, c.p.s. db re db re
Mid-Frequency 10(-13) Watts 10(-12) Watts
------------------------------------------------------------------------
63 98 88
125 97 87
250 100 90
1000 97 87
2000 96 86
4000 93 83
8000 91 81
========================================================================
(3) DUCTWORK. Ducts serving dwelling units shall be lined with duct
lining for at least twenty feet from the fan discharge or intake;
otherwise, an approved sound attenuating device shall be installed
therein. All toilet exhaust ducts shall be lined with duct lining for at
least twenty feet upstream of the exhaust fan intake, otherwise, an
approved sound attenuating device shall be installed therein. Duct
lining shall conform to the requirements of subchapter thirteen of this
chapter.
(4) EXTERIOR MECHANICAL EQUIPMENT. Mechanical equipment in a building
in any occupancy group, when located outside of the building in a yard
or court or on a roof, or where the equipment opens to the exterior of
the building, shall be subject to the noise output limitations given in
table 12-4 where one or more windows of a dwelling unit in any building
in occupancy groups J-1, J-2, or J-3 is located within a sphere of one
hundred foot radius whose center is any part of the equipment or its
housing, unless it can be shown that the sound pressure levels, in
octave bands, of the exterior mechanical equipment as measured within
the dwelling unit do not exceed the levels given in table 12-5.
(For Table 12-4 see chapter 839 of the laws of 1986)
Notes:
a. The minimum distance shall be measured in a straight line
regardless of obstructions. Interpolated levels may be used for
distances between those given in this table. See note a. at end of table
12-3.
1. In the event sound power level data for the exterior mechanical
equipment is not available, the sound pressure levels in octave bands,
of the exterior mechanical equipment shall be measured.
2. The measurements shall be obtained with the microphone of the
measuring equipment located at the interior of the dwelling unit
affected in a line with the window nearest the exterior mechanical
equipment. The window shall be fully open and the microphone shall be
located three ft. away from the open portion of the window.
3. Measurements shall be obtained during times when the ambient sound
pressure levels, in octave bands, are at least six db lower at all
octave bands than the sound pressure levels measured with the exterior
equipment operating. By ambient sound pressure levels is meant the
measured sound pressure levels, at the above described measuring
location, with the exterior equipment not in operation.
b. For permits issued after January first, nineteen hundred
seventy-two, the permitted maximum sound power levels for exterior
mechanical equipment adjoining buildings shall be changed as follows:
(For Table 12-5 see chapter 839 of the laws of 1986)
Notes:
a. Measurements shall be obtained with a sound level meter and octave
band analyzer, calibrated both electronically and acoustically before
and after the measurements are made. The equipment used shall meet the
requirements of reference standards RS 12-6.
b. For permits issued after January first, nineteen hundred
seventy-two, the maximum sound pressure levels shall be changed as
follows:
======================================================================
Octave Bands Decibels
Center Frequencies (cps) re .0002 microbar
------------------------------------------------------------------------
63 61
125 53
250 46
500 40
1000 36
2000 34
4000 33
8000 32
========================================================================
(b) Minimum structure-borne noise and vibration isolation
requirements. All isolators used in accordance with the following
requirements shall be approved.
(1) BOILER ROOMS.
a. Boilers. All boilers supported on floors above a story having
dwelling units shall be supported on resilient isolators having a
minimum static deflection of one inch. The isolators shall be installed
directly under the structural frame of the boiler.
b. Boiler breeching and piping. When boilers are equipped with
mechanical draft fans, the boiler breeching and piping that is supported
from or on slabs, floors, or walls that are contiguous to the dwelling
unit shall be supported for a distance of fifty pipe diameters on or
from resilient isolators. Each isolator shall have a minimum static
deflection of one inch.
(2) INCINERATOR CHARGING CHUTES.
a. Metal chutes. Metal chutes, metal chute supports, and/or metal
chute bracing, shall be free of direct contact with the shaft enclosure
and the openings provided in the floor construction. Metal chutes shall
be resiliently supported at each structural support location. Isolators
shall provide a minimum static deflection of 0.30 in. All chutes shall
be plumb.
b. Masonry chutes. The interior chute wall shall be plumb and without
obstructions for the full height of the shaft and shall have a smooth
interior finish.
(3) PIPING.
a. Metal piping connected to power driven equipment shall be
resiliently supported from or on the building structure for a distance
of fifty pipe diameters from the power driven equipment. The resilient
isolators shall have a minimum static deflection of one inch for all
piping with a four inch or larger actual outside diameter and one-half
inch for piping with less than four inches in actual outside diameter.
Piping connected to fluid pressure-reducing valves, shall be resiliently
isolated for a distance of fifty pipe diameters from pressure reducing
valves and isolators shall provide a minimum static deflection of
one-half inch.
b. Equipment such as heat exchangers, absorption refrigeration
machines, etc., that is located on any floor or roof other than a floor
on grade, and that is not power driven but is connected by metal piping
to power driven equipment, shall be resiliently supported from or on the
building structure, for a distance of fifty pipe diameters from the
power driven equipment. The resilient supports shall be vibration
isolators having a minimum static deflection of one inch and shall
incorporate approved resilient pads having a minimum thickness of
one-quarter inch.
(4) Fans. Except for fans installed in compliance with section 27-353
of article five of subchapter five of this chapter all fan equipment
located on any roof or floor other than a floor on grade shall be
mounted on or from vibration isolators. Fan equipment with motor drives
separated from the fan equipment shall be supported on an isolated
integral rigid structural base supporting both the fan and motor. Fan
equipment with motor drives supported from the fan equipment shall be
mounted directly on vibration isolators. Each isolator shall have
provision for leveling. Isolators shall incorporate resilient pads
having a minimum thickness of one-quarter inch. The vibration isolators
shall provide a minimum isolator efficiency of ninety percent at fan
rotor rpm with a maximum deflection of two inches. Fans and compressors
of three h.p. or less assembled in unitary containers may meet this
requirement with isolators internal to the container providing the
isolators meet the above minimum isolator efficiencies.
(5) PUMPS. All pumps of three h. p. or more located on any floor other
than a floor on grade shall be supported on vibration isolators having a
minimum isolation efficiency of eighty-five per cent at the lowest
disturbing frequency. Each isolator shall incorporate a leveling device
and a resilient pad having a minimum thickness of one-quarter inch.
(6) COMPRESSORS. Compressors and drives located on a floor other than
a floor on grade shall be mounted on vibration isolators having a
minimum isolation efficiency of eighty-five per cent at the lowest
disturbing frequency. Each isolator shall incorporate a leveling device
and a resilient pad having a minimum thickness of one-quarter inch.
(7) COOLING TOWERS. All moving parts of cooling towers located on a
roof or floor other than a floor on grade shall be installed on
vibration isolators providing a minimum isolation efficiency of
eighty-five per cent at fan rotor rpm with a maximum static deflection
of four inches. Each isolator shall incorporate a leveling device and a
resilient pad having a minimum thickness of one-quarter inch.
(8) EVAPORATIVE CONDENSERS. Evaporative and air cooled condensers
located on a roof or floor other than a floor on grade shall be mounted
on vibration isolators providing a minimum isolation efficiency of
eighty-five per cent at fan rotor rpm with a maximum static deflection
of four inches. Each isolator shall incorporate a leveling device and a
resilient pad having a minimum thickness of one-quarter inch.
(9) DUCT CONNECTIONS TO FAN EQUIPMENT. Flexible connections shall be
installed between fan equipment and connecting ductwork.
(10) ELEVATOR MACHINERY. Gear-driven machinery, gearless machinery,
motor generators, and controllers located in an elevator machinery room
or shaft on a roof, or on a floor other than a floor on grade, shall be
supported on vibration isolator pads having a minimum thickness of
one-half inch.
(c) Maximum permissible air velocities in ducts.
(1) DUCTS LOCATED OVER CEILINGS OF DWELLING SPACES. The maximum
permissible air velocity in ductwork located over the ceilings of
dwelling spaces or in masonry shafts adjoining dwelling spaces shall not
exceed the velocities prescribed in table 12-6.
Table 12-6 Maximum Permissible Air Velocities in Ducts
========================================================================
Type of System Branch Ducts Sub-Main Ducts Main Ducts
------------------------------------------------------------------------
Low Velocity 750 fpm 1000 fpm 1500 fpm
High Velocity 1000 2000 3000
========================================================================
In the application of table 12-6 the following shall apply:
a. Any duct that connects directly to any terminal device (grille,
diffuser, etc.) shall be classified as a branch duct for a distance of
at least four feet from the terminal device.
b. Any duct that connects a branch duct to a main duct or to the fan
shall be classified as a sub-main duct. No duct may be classified as a
sub-main duct if it connects to a terminal device by means of a
connection less than four feet in length.
c. When a duct is connected to the fan and to two or more sub-main
ducts it shall be classified as a main duct.
d. The maximum velocities shown in table 12-6 for low velocity
ductwork shall apply in all cases except where a system of round
ductwork is used and an acoustic air control device with self-contained
attenuation components is located in the duct work prior to each air
terminal device. Branch ducts, if any, connecting the acoustic air
control devices to the terminals shall not have air velocities exceeding
seven hundred fifty fpm. Maximum power level ratings for the acoustic
air control devices shall be three db less than the values shown in
table 12-7.
(d) Maximum permissible sound power levels of fan coil units, grilles,
registers, diffusers and induction units. Sound power level data, in
octave bands, shall be certified in accordance with the provisions of
section 27-131 of article seven of subchapter one of this chapter, for
grilles, registers, diffusers and induction units at design operating
conditions and for coil units when operating at specified cfm. The sound
power levels shall not exceed the levels listed in table 12-7 when
measured in accordance with the provisions of reference standard RS
12-5.
Table 12-7 Maximum Permissible Sound Power Levels for Terminal Units(1)
========================================================================
Sound Power Levels, db
Octave Bands, c.p.s. ----------------------------------
Mid-Frequency db re 10(-13) db re 10(-12) Watts
________________________________________________________________________
63 79 69
125 73 63
250 67 57
500 62 52
1000 59 49
2000 57 47
4000 54 44
8000 53 43
========================================================================
Note:
(1) For permits issued after January first, nineteen hundred
seventy-two, the Maximum Permissible Sound Power Level for terminal
units shall be changed as follows:
========================================================================
Octave Bands c.p.s. Sound Power Levels
Mid Frequencies dB re 10(-13) Watts db re 10(-12) Watts
------------------------------------------------------------------------
63 76 66
125 69 59
250 62 52
500 57 47
1000 54 44
2000 52 42
4000 49 39
8000 48 38
========================================================================
To the extent possible under law, Friends of Devin Balkind for Public Advocate has waived all copyright and related or neighboring rights to New York City Administrative Code. This work is published from: United States.
Special thanks to Benjarmin Kallos and Thom Neale who made this content publicly available as a bulk download.