SPECTRO xSORT - Radiation Dose under Various Measurement Conditions; Example 1

Safety
—
24 SPECTRO xSORT — 05.09.2014
2.7 Radiation dose under various measurement conditions
The values of example 1 are based on the TLD measurement method (using
rhodium tubes exclusively!)
2.7.1 Example 1:
Misoperation (unauthorized use)
Measurement conditions:
 No sample
 Shutter open
At the start
button or at
the hand of
the operator
(mSv/h)
At the
window
(mSv/h)
10 cm
(3.9")
(mSv/h)
30 cm
(11.8")
(mSv/h)
100 cm
(39.4")
(mSv/h)
Method for analyzing
metallic samples
< 0.001 3600 360 36 3.6
Method for analyzing non-
metallic samples
< 0.001 36000 3600 360 36
Since the tube would be automatically switched off 100 ms under these
measurement conditions, the following absolute values would result:
At the start
button or at
the hand of
the operator
(mSv)
At the
window
(mSv)
10 cm
(3.9")
(mSv)
30 cm
(11.8")
(mSv)
100 cm
(39.4")
(mSv)
Method for analyzing
metallic samples
< 0.001 0.2 0.02 0,002 0.0002
Method for analyzing non-
metallic samples
< 0.001 2 0.2 0.02 0,002
The maximum permissible dose for the skin and hands, for example in Germany,
is 50,000 µSv per year (this corresponds to 50 mSv/a). In the worst case of 2 mSv,
the operator would have to repeat the misoperation deliberately 25 times in order
to exceed the maximum permissible annual dose. This is a rather theoretical
consideration, since in view of radiation protection every unnecessary radiation
exposure should be avoided.