AT1125 and AT1125A Radiation Monitor

Measurements with marinelli beaker 0.5L
External BDPS-02
Connection to notebook
Show More




The portable high-sensitivity dosimeter-radiometer is designed for search and detection of gamma-ray sources, measurements of the ambient dose equivalent of gamma radiation, flux density of alpha and beta particles with flat-contaminated surfaces, as well as for the rapid estimations of the specific activity of the radionuclide Cs-137 in the samples using Marinelli beaker with volume 0.5L.

Through the use of scintillation detector NaI(Tl) the device AT1125 has a high sensitivity and ability to react quickly to small variations of background radiation, also it allows to fulfill a dose measurements with high accuracy in a wide energy range of gamma radiation using the correction function "spectrum-dose" in the range 0.05 - 3 MeV.

The dosimeter-radiometer AT1125A additionally has a embedded Geiger-Muller counter, which significantly extends the range of measurement of ambient equivalent dose of gamma radiation.

The device has ability to implement the radiometric estimations of samples for radionuclide content using lead shielding in a laboratory and also for express test in the field field environment without any protective chambers.

Type of detectors

Ambient gamma and X radiation dose rate equivalent measurement range

Ambient gamma and X radiation dose equivalent measurement range


Intrinsic relative error limit of dose rate and dose measurement


Energy range of registered X-ray and gamma radiation

Flux density measurement range

   - Alpha particles (BDPS-02)

   - Beta particles (BDPS-02)


Maximum energy range of detected beta particles spectrum



   to gamma radiation of Cs-137

   to gamma radiation of Am-241


Radionuclide specific activity measurement range with 0.5L Marinelli beaker (Rel.error ± 20 %)

  - with lead shield

  - without lead shield

Count rate measurement range

Detection time of the source of Cs-137 with activity 10 kBq at 5 cm distance

Protection class

Overall dimensions


Power supply

Working temperature range

Relative humidity with air temperature ≤35°С

without condensation

Technical and metrological characteristics

Products  >>  Dosimetry  >>  AT1125

AT1125             AT1125A          BDPS-02

Geiger-Muller counter tube

0.1µSv/h - 30mSv/h

0.1µSv ... 1Sv



20keV ... 3MeV

The technical and metrological parameters of each type of detection unit you can find in the

file of description of AT1125 (pdf).

NaI(Tl) Ø25x40mm

30nSv/h - 300µSv/h


10nSv - 10mSv



50keV ... 3MeV

NaI(Tl)Ø25x40mm,  End-type Geiger-Muller counter tube

30nSv/h - 100mSv/h

10nSv -10Sv



50keV ... 3MeV



2.4-1E6 part./(min·

155keV ... 3.54MeV

350 cps∙h/µSv

3800 cps∙h/µSv

50 - 1E5 Bq/kg

100 - 1E5 Bq/kg

< 1E5cps




258x85х67 mm


350 cps∙h/µSv

3800 cps∙h/µSv

50 - 1E5 Bq/kg

100 - 1E5 Bq/kg

< 1E5cps

< 2s



258x85х67 mm


6.6 cps∙h/µSv









138x86x60 mm


Internal rechargeable Ni-MH battery or AC power adapter



  • Facebook Social Icon
TALS OY   Finland  Helsinki

Copyright © 2016. TALS Oy. All rights reserved.