Casella CEL CEL-281 - Manual (Page 23)

Health Authority regulations OSHA 1910.95 "Occupational Noise Expo-
sure".
The CEL-281 is intended to be worn by an individual so that its micro-
phone is subjected to as nearly as possible the same sound exposure as
the wearer (or as otherwise recommended by relevant local legislation).
When necessary, an operator can set the time and frequency weightings
to be used in the measurements, and pre-program start and stop times
and dates for data logging by means of a detachable CEL-6012 Keypad.
This slides on to the dosimeter casing, making contact via a 15-line con-
nector.
Once the operator has made the preliminary settings, it should be possi-
ble for a long series of similar measurements to be made without further
changes. The 16 pressure sensitive keys in the keypad allow a wide
range of parameters and measurements to be selected. These include:
• Choice of A- or C-frequency weightings,
• Choice of Fast, Slow or Impulse time weightings,
• Choice of 10 measurement start and 10 measurement
stop times,
• Measurement of noise levels in decibels (dB) and Pascal-
squared hour (Pa
2
h) energy units,
• Measurement of average and equivalent (L eq ) noise levels
with various exchange rates (Q), threshold levels, and
criterion values,
• Measurement of noise dose in %dose and projected %dose
units with various exchange rates (Q), threshold levels, and crite-
rion values,
• Determination of noise level and equivalent noise level (L eq ) dis-
tribution in terms of cumulative% and probability% with
various sampling periods,
• Measurement of noise, maximum noise, and equivalent noise
(L AVG ) history profiles with various exchange rates (Q) and sam-
pling periods.
CEL-281 Operator's Handbook - Page 15
_Introduction