Casella CEL CEL-181 User Manual
Page 14

Casella USA
17 Old Nashua Road #15
Amherst, NH 03031-2839
9 Calibration Certificate
Instrument Type …………………………………..
Serial No …………………………………………….
Microphone Type …………………………………
Serial No …………………………………………….
Criterion Level (dB) ………………………………
Pa2h (q = 3 vers only) ……………………………..
RMS Time Constant ……………………………..
Amplitude Weighting Function (q) ………………..
Dynamic Range(High) ……………………………
Inst. Overload ……………………………….………
(Low) ……………………………
RMS Overload ……………………………………...
The above noted instrument has been inspected and tested and found to comply with all the
requirements of its relevant specification. The microphone calibration curve for the types CEL-180 is
enclosed with this manual whilst the responses for the other types and details of the other calibration
parameters are retained by the manufacturers under the above-noted serial numbers.
When used with a CEL-182 Dose Meter Calibrator this instrument should be set to a count (on the high
range) of:……………………..
10 ........Modifications and Post Production Developments
Additional Information for US OSHA Regulations
The CEL-181L Personal Noise Dosimeter has the following specification for OSHA classification:
RMS detector characteristic
SLOW
Integration 'q' factor
5 dB (Exchange rate doubling factor)
Measurement range
80-140dB
Criterion level
90 dB
Overload
115 dB RMS continuous
140dB
Instantaneous
Calibration count with CEL-182 9
The relationship between sound level, noise dose count and exposure tine, is as follows for 5 dB
doubling:
L
A
= K + 16.6 log
10
NDC - 16.6 log T
where NDC = % noise dose count and T = exposure time in hours
In the case of dosimeters with criterion levels of 90dB the K = 71.8 and for dosimeters with criterion levels
of 85dB, K = 66.8.
CEL Instruments are manufactured and serviced by:
Casella CEL Inc.
17 Old Nashuia Road #15,
Amherst, NH 03031 USA
PHONE (800) 366-2966
FAX (603) 672-8053
In line with our policy of continual design improvement we reserve the right to amend any of the details in
this handbook.
Issue 1
June 1986
www.casellausa.com
Page 14 of 14
tel:
(
800) 366-2966
27 Jan 2006
fax: (603) 672-8053