The laboratory for strontium and iodine measurements is responsible for the quantitative determination of strontium-90 (by measuring the activity of the daughter product yttrium-90) and iodine-131. These two radionuclides are, together with caesium-134 and caesium-137, the main fission products formed during the uranium-235 fission. For this reason, these radionuclides are very good indicators in case of a possible contamination of the environment following an incident.
This method requires extensive chemical pre-treatment and separation of the radio-elements prior to measurement (i.e. ion chromatographic separation and liquid extraction). Gross beta counting with proportional counters is used measurements is used to determine the radioactivity.
Time Resolved Kinetic Phosphorescence Analysis offers the possibility to measure uranium-concentrations (by mass) in liquid solutions such as water samples or urine samples. The sample preparation is relatively simple and the measurement itself is fast, this making this technique suitable for rapid measurements of uranium content in liquid samples. If the isotopic composition of uranium present in the sample (e.g. natural uranium) is known, the radioactivity content can be calculated from the measured concentration.
The laboratory uses a micro-wave oven for the sample preparation and a Time Resolved Kinetic Phosphorescence Analyser (TR-KPA) to measure the uranium concentration.
Liquid extraction of iodine (Monitoring of 131i in milk).
Contact: Verstrepen Diana