Casella CEL CEL-440 - Manual (Page 14)

Time: F (fast), S (slow),
I
(impulse),
Q: 3, 4, 5, 6 energy conversion factor.
Broadband models can measure all of the following parameters
simul-taneously.
L AF Sound level, with current weightings (A and F
are shown),
L AFmx Maximum level, with current weightings,
L AFmn Minimum level, with current weightings,
L Aeq Equivalent continuous level, with current
frequency weighting,
L AIeq Equivalent continuous level, with impulse
weighting,
L Zpk Linear peak,
L AE Sound exposure level (sometimes known as SEL),
L EP,v Noise dose normalised to a user selected
(variable) period of hours and minutes,
When the period is set to 8 hours, this will be
shown as L
EP,d .
L Tm3 Cumulative average of fast weighted maximum
values taken over 3 s periods (Taktmaximal 3),
L Tm5 Cumulative average of fast weighted maximum
values taken over 5 s periods (Taktmaximal 5),
L AFNN.N Five percentile values using current weightings
with values between 0.0% and 99.9% that can
be set by the user,
TWA v Time Weighted Average is the normalised time
averaged sound pressure level with the selected
frequency and time weighting that represents
the total L
Avg of a person’s workplace noise
exposure averaged over a user selected
(variable) period of hours and minutes.
This unit is specified in the USA: OSHA standard
1910-95 published in 1983. When the period is
set to 8 hours, the unit will be shown as TWA.
L Avg Average level over the measurement period.
Narrow band models can measure and scan the following parameters
simultaneously.
Introduction
Page 14 - CEL-440/480 Operators Handbook