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Noise Control Feasibility
Studies
SCOPE OF WORK
Determine a Design Goal
In order to implement an
effective noise abatement
system, a quantitative
acoustical design goal must be
established. IES 2000 will
provide noise control
recommendations to meet the
OSHA, MSHA, G16 (90dBA), G16A
(85dB(A) criteria requirements.
Determine the Existing
Acoustical Condition
Once the design criteria are
established, baseline acoustical
data would be collected in the
plant and at the operator’s
positions during various
production and non-production
conditions. The recorded data
will be analyzed on the
weighting networks A and linear
scale, 1/1 and 1/3 octaves, FFT
bands covering the
audio-frequency range of 22.5 to
20,000 Hz.
Determine the Required Noise
Reduction
The measured acoustical data
(item 2) is then compared to the
design criteria (item 1) to
identify the noise reduction
required to provide the desired
acoustical environment. The
degree of noise reduction and
the frequency content
requirements are necessary to
design the proper noise
abatement system.
Identify the Sound
Transmission Paths
In order to efficiently
attenuate noise sources, it is
necessary to determine the
transmission path by which the
source affects the receiver.
There could be line-of sight
airborne sound transmission,
structure-borne vibration
transmission, flanking noise,
transmission along ducts, or
penetrations between the noise
sources and receiver. All paths
must be investigated to ensure
an effective abatement system.
Design Potential Noise
Abatement Systems
The abatement system is designed
considering the noise reduction
requirements, frequency content,
sound wave transmission paths,
and operational considerations.
Because the performance of
acoustical materials is
frequency dependent, the design
of the system must consider the
magnitude and frequency of the
source and the degree of
attenuation required. Concept
designs are reviewed with
engineering, production, and
maintenance personnel to ensure
that the operational concerns
have been considered in the
final design. Construction
specifications and costs are
then formulated for each item
and included with concept
drawings.
Final Report
The final report will include
all acoustical analysis and
supporting data, noise control
recommendations, material
specifications, and cost
estimates. This information
allows you to evaluate
acoustical performance versus
cost. Acoustical Systems, Inc.
is then uniquely qualified to
provide a written guarantee that
you will achieve the specified
level, provided that all
practical and functional
recommendation are implemented. |
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Automotive Transfer Press Line |
 Scope:
A large
automotive
manufacturer
wants to
reduce the
noise level
from their
press line 1
A to below
85 dBA for
the job
function
Time
Weighted
Average
(TWA). Press
line 1A
consists of
4 transfer
presses in
sequence
stamping a
variety of
automotive
parts. As
you can
imagine,
each press
requires
access to
load dies.
Access to
the line
between each
press is
different. (Learn More)
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Automotive Engine Test Cell |
Scope: Another automotive manufacturer needed to reduce the background
noise around and engine test cell. Access to the area at multiple points and
ventilation were critical to the success of this project. The noise level
inside the enclosure was reduced to 45 dBA.
(Learn More)
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Glass Furnace |
Scope: Reduce the noise below an 85 dBA job function TWA for the operators
of a large glass furnace. To reduce cost of both the enclosure and the installation,
metal panels were used for noise reduction at the ground level for durability and
curtains were used above the metal panels to reduce noise but also reduce cost.
(Learn More)
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Test Chamber |
Scope: Provide an area on the manufacturing floor where assemblies can be
quickly checked for noise levels. To do this, the background noise must be reduced
from 85 dBA to 40 dBA inside the unit, again, while providing easy access.
(Learn More)
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Noise Exposure Monitoring
IES 2000 has developed
procedures to establish the
occupational noise exposure
as required by OSHA
regulation. These
procedures measure the
exposure level from various
types of noise, such as
continuous, pure tones, and
impulse noise. Reporting is
in accordance with the
latest OSHA and ANSI
Standard S12.19-1996.
Identify employees for
inclusion in hearing
conservation program and
allow for proper selection
of hearing protection based
on noise exposure.
Establish the long term,
full shift, time-weighted
average sound level (TWA)
assessment of individuals or
groups with similar job
activities and noise
exposures. We will assess
the exposure potential for
that individual or group.
Based on the TWA assessment,
we will recommend hearing
protection.
Identify specific areas
for investigation of
engineering or
administrative noise
abatement strategies.
Assess the typical noise
exposure potential over the
long term based upon the
employees’ typical job
assignment. This long term
noise exposure assessment
can be used to recommend
additional noise abatement
strategies.
Provide annual reviews of
noise exposure.
Our monitoring program can
be conducted on an annual
basis in order to determine
if the long term exposure
levels or the employee’s
noise exposure
classification has changed
since the last survey. An
employee’s noise exposure
can change for many reasons
including change in job,
relocation of operation,
addition or deletion of
jobs, or employees, repair
or modification of
equipment, and normal or
abnormal wear of equipment
and length of work shift.
Presentation of noise
exposure report and
database.
Provide a report which can
be used by management
personnel as well as those
involved in various aspects
of the plant hearing
conservation program, such
as medical, safety,
industrial hygiene,
engineering, and legal
personnel. We will compile
the data from the
occupational noise exposure
monitoring into a hearing
conservation database. This
database will not only
assure compliance with OSHA
record keeping requirements,
but also will become a
valuable part of an
effective hearing
conservation program.
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Measurement Location |
Shown in Seconds |
|
RT60 at 500 Hertz |
RT60 at 1000 Hertz |
RT60 at 2000 Hertz |
|
1 |
3.37 |
3.53 |
3.01 |
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2 |
3.84 |
3.66 |
3.21 |
|
3 |
3.64 |
3.69 |
2.94 |
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4 |
3.96 |
3.81 |
2.9 |
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5 |
3.79 |
3.63 |
3.03 |
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6 |
3.98 |
3.71 |
2.86 |
|
7 |
4.1 |
3.91 |
3.03 |
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Average |
3.81 |
3.71 |
3 |
Click on Sound Survey at
Right
for Larger View >>>
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Description |
Wall Treatment (sabins) |
Ceiling Treatment (sabins) |
Total (sabins) |
Predicted RT60 |
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Ceiling Treatment
Only |
0 |
5,184 |
5,184 |
1.67 seconds |
|
Ceiling and Wall
Treatment |
1,664 |
5,184 |
6,848 |
1.40 seconds |
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