Parallel track-etch detector arrangement for radon measurement in soil

A new arrangement using two sheets of parallel track-etch detectors (TEDs) in the open metalic holder for Rn measurement in soil is described. The formula for the response of the system was derived and experimentally proved as the linear function of the gap width between the sheets within the limits 0.5 - 7 mm. The proper choice of the gap width allows to optimise the measuring conditions with respect to both the period of application and the expected radon concentration. The features such as, firmness, small size (outer volume less than 5 cm(3)), simple and compact construction as well as low costs offer this method as the complementary one to the commonly used cup-technique. The preliminary calibrations are described and the results of several pilot field measurements are presented.