ECOTEST VIRTUOSO RKG-14, Operating Manual, Page: 71 / 99

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2. The side of the object the detector is attached to should be selected so as
to avoid visibility of large foreign objects (especially of land, stone facilities or
buildings).
If this is not possible, choose that side, where the external radiation may
be the least.
Figure 2.53 – Measurement near large objects
3. The most simple and correct measurement is obtained when the detector
is attached to the surface on a level open terrain. For example, in case of the
activity measurement in the field (regardless of the object type: stone, sand, fertile
soil, etc.), it is not necessary to put the detector directly to the surface, but one may
hold it at a certain height (up to 1 m). If the NORM are uniformly distributed in the
soil, it will bring almost the same result of specific activity measurement. If NORM
are unevenly distributed, we obtain average activity value for the surface of larger
size, which is sometimes the main task.
4. If it is impossible to avoid visibility of large foreign objects from the
position of the detector, the activity measurement result will be overestimated
(activity of foreign objects will be added to measurement result).
Figure 2.54 – Measurement near large objects