Gamma Spectrometry

Gamma spectrometry is a technique widely used to determine the quality and quantity of gamma-emitting radionuclide concentrations in test samples. The method enjoys numerous possible applications: from monitoring environmental radioactivity, to controlling internal contamination in healthcare physics, to the characterisation of materials to be released during the dismantling of a radiological system.

LBS uses solely high resolution gamma spectrometry systems to determine levels, comprising:

  • Screening well made up of an outer lead layer paired with further internal cadmium and copper screens;
  • Hyper-pure Germanium detector (HPGe) which is cooled with nitrogen or electrically;
  • Digital signal acquisition system comprising pre-amplifier, high voltage generator, digital signal processor and multichannel memory;
  • Dedicated software package for the acquisition, calculation and management of measurements.

LB Servizi can identify and quantify the presence of radionuclides inside all the materials that return homogeneous samples after a suitable treatment process, such as:

  • Biological samples;
  • Industrial samples;
  • Waste;
  • Effluents;
  • Food matrices;
  • Environmental matrices;
  • Building materials.

The field of application includes all the radionuclides characterised by gamma photon emission with energy from 50 keV to 2000 keV.

After arriving at our laboratories, the sample to be tested is prepared by LB Servizi technicians so as to guarantee homogeneity and the possibility of being transferred to the chosen container, reducing it to qualified geometry. Elements that may cause clear diversification of the sample are removed beforehand and measured separately, for example splitting the sample, based on the granulometry or the phases that make it up.

The treatments used to prepare the sample ensure full preservation of the analyte: thermal treatments, in particular, are implemented at lower temperatures to where the analytes being tested evaporate


The test report issued by LB Services contains the following in a single document:

  • The sample’s ID data;
  • Reference to the test method used;
  • Test results, and relative extended uncertainties, with an indication of the coverage factor, for all radionuclides identified in the sample;
  • The detectability limit for the radionuclides of interest that have not been identified in the sample.

 

Applications

Determining the concentration of gamma-emitting radionuclides.


Characteristics

  • Environmental bed;
  • Excellent resolution that allows distinction to be made between two energy distance peaks below 2 keV;
  • Automatic identification system of peaks and subtraction of environmental base, correction of self-absorption, subtraction by coincidences and deterioration;
  • Wide range or reference geometries, thanks to the possibility of determining efficiency by using Monte Carlo modelling codes.

Technical specifications

Reference standard: UNI 11665:2017
Sensitive materials: HPGe dosimeter
Field of application: 50 – 2000 keV