CEL-63x Environmental & Occupational Noise Meter
72
Casella CEL
9
Glossary
The following list defines some of the acoustic terms that you can find in this
User Manual. For additional information, contact Casella CEL or your local
agent.
Acoustic calibrator An instrument that provides a reference noise source with
a standard level and frequency. It is used to calibrate and
the check the performance of sound level meters and
noise dosimeters.
decibel (dB)
The standard unit for measuring sound level and noise
exposure.
dB(A)
A-weighted sound level in decibels.
A-weighted measurements are shown by using the
subscript „A‟.
A standard weighting of audible frequencies designed to
imitate the response of the human ear to noise.
dB(C)
C-weighted sound level in decibels.
C-weighted measurements are shown by using the
subscript „C‟.
C-weighting is a weighting used in the Control of Noise at
Work Regulations, and applies only a relatively small
correction to very loud noise sources.
dB(Z)
Z-weighted sound level in decibels.
Z-weighting applies no weighting to the frequency of
measurement. It is a raw measurement of sound level
across the complete frequency range of the instrument.
Fast time
weighting
A standard time weighting applied to measurements.
Most measurements are made using the Fast time
weighting. When using this setting, the instrument
applies a ⅛-second (125 ms) time constant when
calculating the sound pressure level.
Fast measurements are identified by using the subscript
„F‟.
Impulsive time
weighting
A standard time weighting applied to measurements.
When using this setting, the instrument applies a 35 ms
