Casella CEL CEL-310 - Manual (Page 41)

APPENDIX 1 - GLOSSARY
This Appendix gives a glossary of the acoustic terminology used in this
handbook and in the Dose Badge Personal Noise Dosimeter and Reader.
For further information, please contact Casella CEL or your local
representative. Some of these parameters are shown on the Reader
display, while others require a printer or the computer software supplied.
A-Weighting
A standard weighting of the audible
frequencies designed to approximate the
response of the human ear to noise.
Acoustic Calibrator
An instrument that provides a reference
noise source with a standard level and
frequency used to calibrate and check the
performance of sound level meters and
noise dosimeters.
ANSI S1.25 - 1991
The U.S. Standard for Personal Sound
Exposure Meters.
C-Weighting
A standard weighting of the audible
frequencies. In the Dose Badge system it is
used for the measurement of peak sound
pressure level.
CE Marking
Labels used to indicate that the sound level
meter or noise dosimeter has been
checked to conform with the specification of
a European Directive.
Criterion Level (CL)
This is the normalised eight hour average
weighted sound level in dB that
corresponds to the maximum permitted
daily exposure or 100% noise dose.
In the Dose Badge system, the default
level is 85 dB for ISO measurements and
90 dB for OSHA measurements but it can
be user configured to other levels by means
of the Reader.
Criterion Time (CT)
This is the time, in hours, used in the
calculation of the %Dose and Estimated
%Dose.
In the Dose Badge system, the default
time is 8 hours but it can be user configured
to other durations by means of the Reader.
dB(A)
A-weighted sound level in decibels.
dB(C)
C-weighted sound level in decibels.
Decibel (dB)
The standard physical unit for measuring
sound level and noise exposure.
Estimated Exposure in Pa 2 h
A calculated estimate of the exposure that
would be received by the wearer if the
average level measured continues for the
period defined by the criterion time.
Expressed in Pascal squared hours (Pa
2 h).
Estimated %Dose
A calculated estimate of the %dose that
would be received by the wearer if the
average level measured continues for the
period defined by the criterion time.
For example, if the %Dose was 50%
for a 4 hour measurement, the Estimated
%Dose would be 100% for the 8 hours
Criterion Time.
Exposure in Pa 2 h, Pa 2 s
The measured noise level expressed as a
linear term, in Pa
2 h (Pascal Squared
Appendix 1
CEL-310 Dose Badge Users Handbook - Page 41