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New York City Noise Code - Chapter 28

Section 28-102
a. Portable noise enclosures (so-called "noise tents") made of steel
frames wrapped with noise curtain material, such as SoundSeal model
BBC-13-2, or equivalently rated material, may be built to surround the
jackhammer (on the top and 3 sides) and the operator. A properly
constructed enclosure, using curtain material with a Sound Transmission
Class rating of STC 30 or greater, generally provides a 5 dBA insertion
loss. Such barrier shall meet OSHA standards for worker exposure to
particulate matter.
iii. Portable noise shields made of steel frames wrapped with noise
curtain material, such as SoundSeal model BBC-13-2, or equivalently rated
material, shall be used to form a noise barrier in the direction of
sensitive receptors and completely block the line of sight between the
receptors and vac-truck. Noise curtains are typically made out of a
1/4-inch thick heavy vinyl material, often with a noise absorptive quilt
attached to one side. These noise curtains generally weigh 1.5 lbs/sq.ft.,
have an STC rating of about 32, and come in 4-foot wide sheets complete
with grommets and Velcro edges to aid in hanging the curtains and sealing
the sheets side-by-side.
iii. A noise shroud enclosure shall be wrapped around the head (i.e.
chisel) of the hoe ram whenever working within 200 feet of a receptor.
Shrouds may be selected from various manufacturers such as Krupp
Industries, Allied Hi-Ram, Montabert, or Rammer Inc. with steel shrouds to
attach to the hoe ram head. Alternatively, a shroud may be fabricated
on-site by wrapping the chisel head with a heavy vinyl noise curtain
material, such as SoundSeal BBC-13-2, or equivalently rated material, and
securing it with a tie wire.
iii. Noise curtain material, such as SoundSeal model BBC-13-2, or
equivalently rated material, shall be used to form a noise barrier in the
direction of sensitive receptors and completely block the line of sight
between the receptors and dump truck. It shall also be draped over the
dump truck to augment the engine housing and exhaust stack. Noise curtains
are typically made out of a 1/4-inch thick heavy vinyl material, often
with a noise absorptive quilt attached to one side. These noise curtains
generally weigh 1.5 lbs/sq.ft., have an STC rating of about 32, and come
in 4-foot wide sheets complete with grommets and Velcro edges to aid in
hanging the curtains and sealing the sheets side-by-side.
iii. Noise curtain material, such as SoundSeal model BBC-13-2, or
equivalently rated material, shall be used to form a noise barrier in the
direction of sensitive receptors and completely block the line of sight
between the receptors and auger drill rig. Noise curtains are typically
made out of a 1/4-inch thick heavy vinyl material, often with a noise
absorptive quilt attached to one side. These noise curtains generally
weigh 1.5 lbs/sq.ft., have an STC rating of about 32, and come in 4-foot
wide sheets complete with grommets and Velcro edges to aid in hanging the
curtains and sealing the sheets side-by-side.
iii. Portable noise enclosures made of steel frames wrapped with noise
curtain material, such as SoundSeal model BBC-13-2, or equivalently rated
material, shall be built to surround (top and 3 sides) the concrete saw
and the operator. A well made enclosure, using curtain material with a
Sound Transmission Class rating of STC 30 or greater, can generally
provide a 5 dBA insertion loss providing there are no gaps in the
enclosure. Noise tents may be reused at other sites with proper care and
maintenance.
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