Calibration - Fuji Electric NRF51 User Manual

Calibration

9.3
This section describes the calibration procedures for NRF51.
Expose NRF51 to the gamma-ray sources such as
as 252 Cf or Am-Be.
A dose should be measured by placing the source at a certain distance (calibration distance)
from reference point of NRF51 so that true value of the dose is traceable to the National
Standard.
(1) Determination of a reference dose value (R
Determine a reference dose value (R
-
a. Calculate R
source and reference point of NRF51 (calibration distance) and irradiation time.
b. Or the dose rate value at the reference point may be simply well-known by field
calibration/characterization. In this case, reference dose value (R
by the known dose rate value and irradiation time.
(2) Dose value (R
- Place the source at the calibration distance from reference point of NRF51.
- Take the dose reading (R
(e.g. 1 mSv)
from the reference source activity, the distance between the reference
0
) measurement
1
) after irradiation which gives enough statistical stability.
1
137 Cs and
)
0
) by the following method:
0
60 Co and neutron sources such
) can be calculated
0
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