Description and contact

Contact: LLC "ELRA", Russia, St. Petersburg, Volkhonskoye highway 150. Email dozimetr.spb @ yandex.ru, phone: 0079013001092.

1. Application
Detector - indicator of radioactivity (the indicator) allows for evaluation of radiation environment and contamination of foodstuffs, building materials, clothing etc., with radioactive substances. The indicator assesses the level of equivalent dose power (EDP) of contamination with sources of gamma rays and beta particles of the environment and various objects. The instrument indicates the EDP on the digital display and emits a prolonged audible signal indicating excess of EDP level.

2. Main characteristics
Sensor - CRT Geiger-Muller counter SBM-20U Ц 1 pc.
Dial range, mcSv/hour - 0 Ц 9.99
Count cycle, sec Ц 30
Indication and sound alarm with possibility to switch off and count the photon emission
EDP threshold exceeded alarm, mcSv/hour Ц 1,25
Indication of power supply discharge
The duration of continuous work, in conditions of natural background radiation, with power supply fro battery Energizer 6LR61, hours - at least 180
Working temperature range, in degrees ╤ Ц -10 +40
Dimensions, mm Ц 130ї70ї24
Weight, kg (without batteries), 0,13

3. Short description of indicator
On the front panel there is the liquid crystal display (hereinafter LCD) divided into four indication zones:
лparticles╗ Ц indication of registered photons through a zero at the beginning of each measurement cycle;
лdose rate╗ Ц EDP indication for the last cycle of measurement, in mcSv/h;
лaverage dose rate╗ Ц Indication of EDP DER averaged over four cycles of measurements in mcSv/h;
лlevel╗ Ц EDP threshold indication in mcSv/h.
On the top cover there is a button acting as power on and off, as well as "reset" and disabling the sound signal during counting the particles.

4. Operating instructions
The indicator is switched on/off by pressing and holding a button for more than 2 seconds. Immediately after turning on the LCD appears the inscription: лGAMMA╗, лReady to use╗ and then, if the button is released, the detector begins a series of measurements. By further holding the button display shows лon / off sound╗ and then after 2 seconds, the inscription лsound off╗ and registration of the particles will be not accompanied by sound signals.
The digital display indicates the number of particles counted by dosimeter from the beginning of the cycle. At the end of the cycle time in the zone лdose rate╗ the value EDP appears. After four cycles of measurements in the area of лaverage dose rate╗ the EDP value averaged over four cycles of measurement appears. In case of exceeding the threshold of the EDP value, the alarm beep is emitted and the bottom line of the LCD will display л! DANGER!╗. Alarm will sound until the next measurement cycle begins (i.e., 120 sec.). If the EDP value during this time becomes lesser than the threshold, the alarm stops. The indicator monitors the battery charge level, if the battery charge is low, the bottom line of the LCD displays лLOW BAT╗.
By pressing the button it is possible "to reset" all measured values. After that, all measurements begin anew. If you press and hold the button for 3 seconds, the message лgood-bye╗ appears, and the device shuts down.

5. How to perform the test
Since ionizing radiation is of probabilistic nature, the separate cycles account statements may differ significantly. Value in the area of the indicator лdose rate╗ is given only as a guideline. The appearance of the average values in the area of лaverage dose rate╗ allows for evaluation of the level of DER. To determine the radioactive contamination of foodstuffs, household items, etc. at first it is necessary to determine the value of the natural background, including appliance, at least two minutes before the test. Then the device shall be brought close to an object at a distance of 10 mm. A significant increase in readings indicates that the object is contaminated with radiation.