Curves; Captured Curves; Captured Curve Applications - 3M SP-SE-2-1/1 User Manual

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Curves

Captured curve applications

Curves
Curves, also referred to as "Acoustic Spectral Curves", is used to evaluate
the quality of noise in new or existing buildings. The SoundPro models SE
and DL support the following:

Captured curves

Captured Curves, is a user-defined criterion curve, which allows the user to
make a measurement with a 1/1 octave band frequency or a 1/3 octave band
frequency distribution and save or capture the spectral curve. This snapshot
can be displayed in DMS as a baseline or reference curve. A new
measurement is then made and superimposed over the captured baseline
curve to illustrate octave band frequency deviations from the original
distribution, creating a user-defined criterion curve. This may be kept just as
a reference, or it may be used as an evaluation for product or process
comparisons, job task risk assessments, environmental investigations, and
other applications.
Captured curve applications
 Application 1 - Baseline: Applying a captured curve as a baseline or reference
curve for noise abatement investigation.
•
 Application 2- Quality Control: Using a captured curve as a Quality Control (QC)
evaluation. The instrument has been pre-loaded with a sound curve that represents
the allowable levels for some product.
•
 Application 3: Process monitoring: A set of machinery is monitored to watch for
changes in the operating sound.
•
Captured curves
•
Noise Criterion curves: NC curves, PNC curves, NCB curves, NR
•
curves, RC curves,
Audiometric Booth Background Curves: ANSI 53.1, OSHA, and ISO
•
AM Booth
The operator captures the original noise and then makes various changes to the
machine and/or enclosure and looks to see how much of a difference the change
made.
Once the product comes off the assembly line, it runs and the measurements are
compared to the allowable levels. If levels exceed the curve, it is sent back for
rework.
If the measured sound exceeds the sound curve, it is an indication to the operator
that "something bad" is happening (i.e., over exposure) and he needs to shut
things down and call maintenance before more damage occurs.
Models SE and DL