2.3.2 Inspection procedure.
During the inspection you should use the «Guidelines for objects survey» (see art.
2.2.4).
After switching on the product the radiological situation estimation starts. During the
measurement period each detected quantum of radiation is indicated on the display with
the icon « » and a short beep if the sound is turned on and the threshold is off.
Frequency of this icon indication is proportional to the dose rate or flux density of beta
particles. In 21 s after switching the product the result of the first cycle is displayed.
The following cycles are accompanied by the icon change, and the averaging of the
results.
The icon « » corresponds to one measurement cycle;
« » - corresponds to eight or more measurement cycles
The second result is displayed as the average of the first two measurement cycles,
the third – as the average of three measurement cycles and then every subsequent result
is the average of eight previous measurements.
By averaging the result the product analyzes the current value error with regard to
outcome of the previous measurement. If the difference exceeds a certain value, the
display shows the current result and not the average. For example, based on several
observations made the average result is 0,20 µSv/h, and in the current cycle
registers 0,80 µSv/h, then the result will not be averaged and you will see the 0,80
µSv/h and the icon « » on the display. This algorithm allows to measure the sharp
changes in the gamma- and beta-radiation intensity.
Searching for the radiation source can be carried out in the mode «SEARCH» or and
in the «MEASURE», but the «SEARCH» is more convenient, since the cycle in this profile
is twice shorter.
During searching for the radiation source switch off the threshold, switch on the ring
and pay attention not only to the digital readout, but also to the frequency of the sound
signals and the frequency of the icon « » appearance. The frequency of their occurrence
is proportional to the flux density or rate of beta-particles, the higher the frequency, the
closer you are to the source.
2.3.3 Carrying out the radiation inspections of residential and public buildings.
Evaluation of radiation dose in open area (of background) is carried out near the
surveyed building is not less than on 5 points located at a distance of from 30 to 100 m
from the existing buildings and no closer than 20 m from each other. Measuring points
should be chosen on a site area with natural ground, with no man-made changes (gravel,
sand, asphalt) and radioactive contamination. During the estimation the product should be
at a height of 1 m above the ground.
The total time of the background radiation dose evaluation is 20 - 25 minutes, but if
you want to get reliable results, it is necessary to carry out a survey in its entirety.
For the survey convenience the product has the additional mode «BACKGROUND»
(art. 1.3), which facilitates the survey.
::: GAMMA ::::: ::::::::::::
0,12
0,30
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::: BETA ::::::::::::::::::::::
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