Establishment of the 222Rn traceability chain with the Romanian standard system

This paper presents the results obtained in the establishment of the upper level of the traceability chain, primary and secondary 222 Rn measurements, with the standard system realized at IFIN-HH, Romania. The following subjects are presented: (i) the principle of establishing the traceability chain; (ii) the setting up of the final metallic system for the radon standardization and the experimental method; (iii) results obtained in the realization of the traceability chain, by absolute radon standardization with the liquid scintillation counting method (LSC) and relative measurements of activity, using the HPGe gamma-ray spectrometry method and the CENTRONIC IG12/20A ionization chamber, and its validation. The final purpose of the work is to calibrate adequately the secondary standard systems, HPGe spectrometer and ionization chamber, for using them in the measurement of the working standards, various types of recipients containing radon gas, prepared in the laboratory with the radon system.