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THE PRIMARY ROMANIAN RADON STANDARD, A COMMON PROJECT: IFIN-HH, BUCHAREST; ICSI, RM.VALCEA; ISP, TIMISOARA; CEA/LNE-LNHB, SACLAY (FRANCE)
Maria Sahagia1*, Aurelian Luca1, Anamaria Cristina Wätjen1, Andrei Antohe1, Constantin Ivan1, Doru Stanga1, Carmen Varlam2, Ionut Faurescu2, Laszlo Toro3 Mihaela Noditi3, Philippe Cassette4
1„Horia Hulubei” National Institute of R&D for Physics and Nuclear Engineering, IFIN-HH, 077125 Bucharest, Romania
ABSTRACT
The paper presents the following problems which were solved during the deployment of the project: · Elaboration of the radon standard concept: (i) design of the radon system: the radon generator source, the circuit for circulation, transfer, recovery ; (ii) choice of the standardization method; (iii) conception of an original traceability chain; (iv) definition of the basic requirements according to the international and national Norms regarding the monitoring and reporting of the radon concentration. · Realization of the radon circuits, in two variants: (i) the preliminary one, from glass, used to demonstrate the feasibility of the system; (ii) the final, metallic variant, provided with the necessary gauges for the control of pressure level and of radon circulation and recovery. · Elaboration of the method for the absolute standardization of the equilibrium radon decay chain, by liquid scintillation counting (LSC). · Realization of various types of recipients, with radon as gas and dissolved/adsorbed in liquid scintillator, and their measurement by HPGe gamma-ray spectrometry, ionisation chamber and LSC. Elaboration of a computing model for radon circulation in various matrices: soil, water and active charcoal. · Establishment of the traceability chain, from the primary standard to the calibrated secondary equipments and preparation of radon recipients with the radon activity certified. · Study of the LS efficiency influence on the radon measurement.
KEYWORDS: Primary radon standard system; Liquid scintillation counting; Equipment calibration *Corresponding author: e-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it 2National Research and Development Institute for Cryogenics and Isotopic Technologies - ICIT Rm. Valcea, code 240050 - Rm. Valcea, Uzinei 4, CP7 Riureni, Valcea, Romania, phone: +40 250 736979, fax: +40 250 732746 3Institute of Public Health, Regional Centre Timisoara, ISPT, Romania 4CEA/LNE-LNHB Laboratoire National Henri Becquerel – CEA Saclay, 91191 Gif-sur Yvette Cedex, France |