Mirion Technologies DMC 3000, Руководство пользователя

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151153EN-G
DMC 3000 User's Guide
8- M
anual C
alibr
ation & M
ain
tenanc
e
8.1 Manual Calibration
This method can be used for the DMC 3000 itself and for any attached module. For attached module, as the
calibration parameters are saved on the module itself, Module may be calibrated on any compatible DMC
3000 as a host for the calibration process
One specific efficiency coefficient multiplier is available for each type of measurement ( H p(10) gamma,
H p(0,07) X + Gamma, H p(0,07), Beta H p(10) neutron).
Use the proper source depending on the type of measurement.
Hereafter is the method for the H p(10) X+Gamma calibration:
„
Expose the dosimeter with a gamma source
137
Cs (note) to a minimum dose of 500 µSv, that is the expected
dose and read on the dosimeter display the "Read Dose."
„
Look up the H p(10) Gamma Efficiency Coefficient Multiplier using
dmc
User
software. This calibration factor
is called " K OLD ".
„
Determine the new H p(10) Gamma Efficiency Coefficient Multiplier "
K NEW
" using the following equation:
K NEW
=
K OLD
x Read dose / Expected dose.
„
Turn off the dosimeter and set the H p(10) Gamma Efficiency Coefficient Multiplier to the new value
" K NEW " using
dmc
User software.
„
Expose the dosimeter with the same source and check that the response of the dosimeter is within the limit.
Note:
The DMC 3000 is equipped with 2 detectors, one for high energy gamma and >50 kev X-ray and a second detector for low energy
X-ray down to 15 kev. Calibration with a Gamma source (
137
Cs or
60
Co) or Gamma source and low energy X-ray may be conside-
red based on service environment. Mirion Technologies provides a calibration check at 3 energy levels (16 keV X-rays,
241
Am and
137
Cs) and
60
Co on request, in accordance with ISO/IEC 17025 (COFRAC accreditation Nber 2-1663).
- In G3 protocol Hp(10) Gamma Efficiency Coefficient Multiplier is set at 1.00 in factory.
- Decreasing the Hp(10) Efficiency Coefficient in G2 protocol or Hp(10) Gamma Efficiency Coefficient Multiplier in G3 protocol will increase
the DMC 3000 response.