Polimaster PM1603A User Manual

33
А.7.3 Determination of metrological data
А.7.3.1 To determine the intrinsic relative error of the DER measurements the
following operations should be performed:
1) enter the DER mode using the MODE button;
2) place the dosimeter on a dosimetric verification assembly so that the graduation
direction should coincide with the direction of radiation flow and the longitudinal axis of
radiation flow should pass through the geometric center of the detector. Graduation
direction and geometric center of the detector are marked in the operating documentation;
3) calculate the average background value of dosimeter’s readings at the absence of
gamma radiation source. For this in no less than 300 s after placing the dosimeter on a
dosimetric verification assembly and at intervals of no less than 150 s take dosimeter’s
readings and calculate the average DER background value
•
Η
b, in mSv/h, by formula
∑
=
=
n
i
bi
b
H
n
H
1
1

(1)
where n - is the number of measurements equal to 10 for PM1603 modification and
equal to 5 for PM1603A and PM1603B modifications;
Η
•
b
i
- is the dosimeter’s reading at i-measurement of DER background, in mSv/h.
Note – For PM1603A and PM1603B dosimetes the measured DER background values
in the range of 0.001-1.0 mSv/h are indicated in µSv/h, so when calculating the average
value of DER it is necessary to transfer µSv/h in mSv/h.
4) create DER = 0.003 mSv/h from the
137
Cs gamma radiation source at a point of
the geometric center of the detector and irradiate the dosimeters;
5) in no less than 100 s after the beginning of irradiation and at intervals of no less
than 60 s take the dosimeter’s readings and calculate the average value H
j
, in mSv/h, by
formula (2); during this the indicator of DER value on the analogue scale must come into
the first sector for PM1603 dosimeter and one segment should be indicated for PM1603A,
PM1603B dosimeters:
∑
=
=
•
n
1i
ji
j
H
n
1
H

(2)
where n – is the number of measurements in every point equal to 10 for PM1603
dosimeter and equal to 5 for PM1603A and PM1603B modifications;
Η
•
ji
– is the dosimeter’s reading at i-measurement in the tested point of DER, in mSv/h;
6) repeat measurements for the points where DER value is equal to 0.08 and
0.8 mSv/h correspondingly; the indicator of the analogue scale must come in the second
sector for PM1603 dosimeter. Two segments should be indicated for PM1603A and
PM1603B dosimeters when DER is equal to 0.08 mSv/h and three segments should be
indicated when DER is equal to 0.8 mSv/h;
7) create DER equal to 8.0 mSv/h at a point of the detector geometric center;
8) irradiate the dosimeter;
9) in no less than 60 s after the beginning of irradiation and at intervals no less than
20 s take the dosimeter’s readings and calculate the average value of H
j
by formula (2);
during this the indicator of DER value on the analogue scale must come into the third
sector for PM1603 modification and four segments should be indicated for
PM1603A PM1603B modifications;
10) repeat measurements for the points where the DER is equal to 80.0 and
800 mSv/h. Repeat the measurements for PM1603 and PM1603A dosimeters for the point
where DER value is equal to 4000 mSv/h. Repeat the measurements for PM1603B
dosimeter for the point where DER value is equal to 8000 mSv/h. During this the indicator
of the analogue scale must come to the fourth and then to the fifth sector for PM1603
modification. For PM1603A and PM1603B modifications five segments should be indicated

Polimaster PM1603A Specifications

General

Brand	Polimaster
Model	PM1603A
Category	Measuring Instruments
Language	English