04/03 347 LB 444
86
Distance
DISTANCE
This means the distance between radioactive source and
human body. The radiation intensity (dose rate) decreases
– like light – in proportion to the square of the distance, i.e.
doubling the distance to the source reduces the dose rate to
one quarter.
Conclusion:
When handling radioactive substances, maximum distance
to the source should be maintained. This is especially true
for persons not directly involved in this work.
Time
TIME
The total time a person stays in the vicinity of a radiometric
measuring system and the body is exposed to radiation.
The effect is cumulative and increases therefore with the
duration of the radiation exposure.
Conclusion:
Any work in the vicinity of radiometric measuring system
has to be prepared carefully and organized such that it can
be carried out in the shortest time possible. Having the
proper tools handy is of particular importance.
Shielding
☺
SHIELDING
The shielding effect is provided by the shielding material
surrounding the source. As the shielding effect depends,
following an exponential function, on the product of thick-
ness multiplied by the density, it follows that material with
a high specific weight will normally be used for shielding.
Suitable dimensions are usually calculated by the supplier.
Conclusion:
Before installing or dismantling the shielding, make sure the
radiation exit channel is closed. The source must not be
removed from the shielding and not remain unshielded.
To Next Page
Loading...
