E-Perm measurement of the radon flux from undisturbed soil

The study described in this paper was initiated to demonstrate the use of E-Perm radon detectors for the measurement of the radon flux from undisturbed soil. The method consisted of measuring the radon concentration in a container placed open face down on the soil with a known airflow through the container. From the soil are enclosed, the airflow rate, and the integrated radon concentration measured in the container, the radon flux from the soil surface is calculated. The radon flux values obtained from selected sites in central Pennsylvania using the E-Perm detectors were in agreement with the values obtained using a Pylon AB-5 detector with a lucas cell attachment (correlation coefficient = 0.986) and from soil gas measurements. The values for the radon flux are also comparable to the values reported in the literature by others. The primary factor influencing the radon flux was concluded to be the soil moisture content. The advantage of this method is that the radon flux at the soil surface is determined with a simple relation without having to know site soil parameters. Since the application of the system would entail deployment at remote sites, the system was designed to be portable, rugged, self-powered, and minimize the risk from theft and damage