Abstract: The invention describes a method and a device for the continual and, in particular, for a fast detection of changes of the concentration of radon gas dissolved in water by means of a transfer into a measuring gas (Rn-222), which can be adopted for a variety of monitoring, control and regulation assignments. The invention is based on the fact that a membrane, which is permeable for the radioactive noble gas radon but extensively non-permeable for water, is circum-flushed on the one side of radon-containing water and on the other side of the carrier gas with, in each case, optimised flow velocities either in parallel or in counter-flow When stable peripheral conditions are ensured, the concentration of radon in the measuring gas is directly proportional to the concentration of radon in the water.

Abstract: The invention describes a method and apparatuses for characterizing groundwater measuring sites by differentiating between groundwater and static water and serves, for example, for determining the pumping-out times of groundwater measuring sites, optimum for investigations of the representative nature, as well as for identifying and localizing defects at groundwater measuring sites. The invention is based on measuring the radon activity concentration or the total activity concentration of the groundwater samples. The measurement of the concentrations by offline or online methods permits the ratio of groundwater to static water in a groundwater measuring site to be determined reliably. A novel flow-through measurement cell, as well as a borehole probe are described The invention can be employed wherever investigations of the nature of groundwater are carried out.

Abstract: The invention describes a method and a device for the continual and, in particular, for a fast detection of changes of the concentration of radon gas dissolved in water by means of a transfer into a measuring gas (Rn-222), which can be adopted for a variety of monitoring, control and regulation assignments. The invention is based on the fact that a membrane, which is permeable for the radioactive noble gas radon but extensively non-permeable for water, is circum-flushed on the one side of radon-containing water and on the other side of the carrier gas with, in each case, optimised flow velocities either in parallel or in counter-flow When stable peripheral conditions are ensured, the concentration of radon in the measuring gas is directly proportional to the concentration of radon in the water.

Abstract: The invention describes a method and apparatuses for characterizing groundwater measuring sites by differentiating between groundwater and static water and serves, for example, for determining the pumping-out times of groundwater measuring sites, optimum for investigations of the representative nature, as well as for identifying and localizing defects at groundwater measuring sites. The invention is based on measuring the radon activity concentration or the total activity concentration of the groundwater samples.

Abstract: The invention describes a method and apparatuses for characterizing groundwater measuring sites by differentiating between groundwater and static water and serves, for example, for determining the pumping-out times of groundwater measuring sites, optimum for investigations of the representative nature, as well as for identifying and localizing defects at groundwater measuring sites. The invention is based on measuring the radon activity concentration or the total activity concentration of the groundwater samples. The measurement of the concentrations by offline or online methods permits the ratio of groundwater to static water in a groundwater measuring site to be determined reliably. A novel flow-through measurement cell, as well as a borehole probe are described. The invention can be employed wherever investigations of the nature of groundwater are carried out.