Intercomparison between Radon Passive and Active Measurements and Problems Related to Thoron Measurements

Researchers around the world had already established that radon and thoron are a hazard to the human health. Different techniques and methods are applied in order to measure them as accurately as possible. In Romania, most measurements earlier conducted were focused on using grab-sampling measurements to establish the two gasses decay progeny activity concentration; however, recently, there has been an increased interest in using passive devices together with active devices for long-term measurements. In order to get more accurate knowledge about the real radon and thoron indoor concentration in dwellings as well as in public buildings and work places, a new survey was carried out in 15 locations within and surrounding Birlad Town, Vaslui County. Passive methods including two types of discriminative detectors based on CR 39 chips as well as active measurements, such as RAD7 were used for this survey. During this survey, it was also pointed out the continuous difficulty in measuring thoron, due to its short half-life and faults in the measuring system.