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CALIBRATION OF INSTRUMENTS MEASURING RADON OVER A LARGE ACTIVITY RANGE

N. Michielsen, V. Voisin Institut de Protection et de Sûreté Nucléaire, Département de Prévention et d’Etude des Accidents, Service d’Etudes et de Recherches en Aérocontamination et en Confinement, CEA/Saclay, Bât.389, 91191 Gif-sur-Yvette Cédex, France

A newly built radon calibration test bench called BACCARA is presented. A method of calibration using a secondary 222 Rn standard is described and examples of calibration are given. With this
method, no reference instrument is needed and one obtains a more accurate determination of the 222 Rn volume activity.

Key words : calibration test bench, radon, radon standard