RKI Instruments GD-70D Series, Руководство по эксплуатации

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GD-70D
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Safety of the radioisotope 241Am (37 KBq) used in the pyrolysis-particle type
sensor
The pyrolysis-particle type sensor installed in the gas detector uses the radioisotope 241Am radiation
source (18.5 KBq x 2 = 37 KBq).
A specified designing certification device must satisfy the specified threshold for "1 cm dose equivalent
rate at a point 10 cm away from the surface of the device" as a certificate condition, which is the
following value (tolerable amount).
Tolerable amount
1 cm dose equivalent rate at a
point 10 cm away from the
surface of the device
1
μ
Sv•h
-1
This detector which uses radioisotope
241 Am radiation source (18.5 KBq x 2 = 37 KBq) has the following 1
cm dose equivalent rate at a point 10 cm away from its surface, meaning that it completely satisfies the
certification condition.
1 cm dose equivalent rate at a point 10 cm away from the surface of
the sensor (calculated value)
cm
r
Q
D
1
2
Γ ⋅ =
( )
019 . 0 00524 . 0
1 . 0
10 5 . 18 2
2
3
= ⋅
× ×
=
−
[
μ
Sv•h
-1
]
Q
: Amount of radioisotope 2 x 18.5 x 10
-3
[MBq] =(37KBq)
cm 1
Γ
: 1 cm dose equivalent rate constant of
241
Am 0.00524 [
μ
Sv•m
2
•MBq
-1
•h
-1
]
r
: Distance from radiation source 0.1[m]
It is certified as a safety device, provided that it is used in accordance with the certification conditions
specified in the "Safety Manual".