Investigation of the influence of high humidity and exposure duration on the measurement results of radon concentration by means of PicoRad system in the CLOR calibration chamber

• Autorzy: Stawarz O. , Karpińska O. , Mamont-Ciesla K.
• Konferencja: Proceedings of the IV All-Polish Conference on Radiochemistry and Nuclear Chemistry9-11 May 2005, Kraków-Przegorzały, Poland
• Języki publikacji: EN

Abstrakty

EN

PicoRad system based on activated charcoal collectors and liquid scintillation counter is one of the most popular passive methods of radon measurements which may be used both indoors and in other environments such as caves, tunnels, mines etc. It is well known that charcoal is also a very good adsorber of water vapor and it can reduce adsorption efficiency for radon. In PicoRad collectors, the charcoal is mixed with a dessicant to lower this effect. A series of expositions of PicoRad detectors was performed in a Central Laboratory for Radiological Protection (CLOR) radon calibration/climatic chamber to study the effect of high relative humidity on the airborne radon concentration measurements and the dependence of the results on the duration of exposure. The results obtained from the PicoRad system were referred to the mean concentrations delivered by an AlphaGUARD monitor, Genitron (GmbH), Germany. The main conclusions are the following: 1) the PicoRad system results are not affected by high relative humidity, including extreme values of 90-96%, for the duration of exposure up to ca. 24 h; 2) in the relative humidity range of 75-96% the correction coefficient linearly depends on the duration of exposure reaching a value of ca. 16 for 96 h exposure; 3) the PicoRad system delivers results corresponding better to the mean value of radon concentration in the last 6 h interval of exposure than that in the whole exposure duration. This finding is particularly important for the calibration of PicoRad collectors in the conditions of decreasing radon concentration due to radon decay.

Słowa kluczowe

EN

radon; activated charcoal; relative humidity; duration of exposure; PicoRad system

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2006
• Tom: Vol. 51,suppl.2
• Strony: 53--57
• Opis fizyczny: Bibliogr. 12 poz., rys.

Twórcy

autor

Stawarz O.

autor

Karpińska O.

autor

Mamont-Ciesla K.

• Dosimetry Department, Central Laboratory for Radiological Protection, 7 Konwaliowa Str., 03-194 Warsaw, Poland, Tel.: [phone], Fax: [phone],

Bibliografia

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