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4.2 Dose rate measurements
The unit displays the dose rate values in "µSv/h, "mSv/h", and "Sv/h" (or "µR/h, "mR/h", and
"R/h"). As the dose rate increases, the instrument switches these measurement units
automatically.
The statistical error of the measured dose rate value is shown in the upper right corner of the
display in percents with 0.95 probability. The dose value may be used when the statistical error
is 15 % or less.
The measured dose rate value is displayed graphically as well. The number of lighting analogue
scale segments represents the measured dose rate value relative to the preset threshold (Figure
4.2).
To view the current dose rate threshold, press the SET button (Figure 3.2). To return to the dose
rate screen, press the SET button again:
Dose equivalent rate screen
Dose equivalent rate threshold screen
Figure 4.2 – The dose equivalent rate (DER) and DER threshold screens
The manufacturer presets the DER threshold value at 1 µSv/h.
The DER threshold setting range corresponds to the DER measurement range (refer to section
2.2).
If the preset DER threshold is exceeded, the analogue scale is fully filled, the audible alarm
sounds (monotonous triple signals with 1 second interval) and the display is blinking (the visual
alarm). This event (the DER threshold exceeding) is stored in the unit non-volatile memory.
If the dose equivalent measurement range is exceeded (overload condition), the
instrument activates the audible signal (monotonous triple signals with 1 second
interval) and displays "OL".
"
PM2012M Data Processing Software
" (on memory drive included with the unit)
enables the operator
to set
the DER threshold and to change the dose equivalent rate
measurement units from Sv/h to R/h and vice versa.
SET
SET
analogue scale
