Internal Dosimetry Laboratory
Purpose
The Internal Dosimetry Laboratory is used to obtain measurement data on levels of radionuclides in the whole body, in organs or other tissues and of their rates of excretion, to be used as a basis for assessing intakes and for calculating committed tissue or organ equivalent doses and committed effective doses.
The Internal Dosimetry Laboratory operates a Whole Body Counter, a chemical treatment laboratory and a spectrometry laboratory for urine analysis.
Whole Body Counter
The Agency's Whole Body Counter was first installed (1962) in the previous IAEA Headquarters, in Vienna, then transferred (1978) to the Seibersdorf Laboratory. In a low background chamber (250x180x220 cm), made of 18 cm thick steel, 1 cm Pb and 1 mm electrolytic Cu. Several detector system have been operational over few years, namely:
- Four NaI(Tl) detectors for high energy photon detection replaced in 1998 by four HPGe detectors
- Two "Phoswich" detectors (5"x2") with 1 mm Be window and 3 mm thick NaI(Tl) crystal, for low energy (6-100 keV) photon detection
During 2003 two Broad Energy HPGe detectors replaced all those detectors for measuring with different electronic setting the low energy and high energy photons.
A set of phantoms for the calibration of the facility is available, among them: the BOMAB, thyroid, Livermore and the knee phantoms.
Urine Analysis
The Agency's Urine Analysis Laboratory is equipped for the treatment and monitoring of urine samples for gamma, alpha and beta content emitters, in three separate laboratories installed at Seibersdorf:
The gamma emitters detection is performed on urine samples, collected in one liter plastic bottles, by mean of two Germanium detectors, in 10 cm lead shielding. Each detector is connected to a Spectrum Master Gamma Spectroscopy Workstation controlled by a PC
The alpha emitters detection is performed after sample chemical treatment. This includes evaporation, mineralization and exchange resin chromatography, on the residue obtained on a membrane filter. A microwave digestor is used all over the process. The measurement is done by mean of ion-implanted silicon detectors (2x8), in vacuum chambers of the Alpha Spectroscopy Workstation
The beta emitters detection is performed by an automatic Liquid Scintillation Counter
For further information please contact Rodolfo Cruz Suarez
