Institute of Radiation Protection

Internal dosimetry

whole body counter
Fig 1: Photography of the whole body counter

In vivo measurements with a whole body counter

Motivation

  • Measurement of incorporated radionuclides in humans in-vivo
  • dose estimates after incorporation of radioactive substances
  • routine monitoring of the population
  • investigations after specific radionuclide intakes

Experimental setup (Fig. 1)

  • Shielding chamber: 310 m x 370 m x 360 m
  • Materials used: Sand: 70 - 80 cm (~10t); steel: 5 - 15 cm (~ 30t); lead: 0,5 cm (~1t)
  • 4 NaJ-detectors (4 inch x 5 inch) + 4 Photomultiplier
  • Detectable radionuclides: e.g. 40K (primordial), 60Co and 134Cs (activation products), 137Cs (fission product) (Fig. 2)
  • Calibration : bottle phantoms of different sizes
spectrum measured
Fig 2: Example of spectrum measured after the Chernobyl accident (priv.com. D. Berg)