3M SE, DL user manual Curves, Captured curves, Captured curve applications

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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

•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

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.

•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.

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.

•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.

Application 3: Process monitoring: A set of machinery is monitored to watch for changes in the operating sound.

•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