Radon monitoring in water sources of Balakot and Mansehra cities lying on a geological fault line.

This paper relates to a series of systematic studies regarding measurement of radon concentration in the earthquake-affected areas of northern Pakistan. Radon is a radioactive alpha-particle-emitting gas originating from the decay series of uranium and thorium and is found anywhere in soil, air and water. The nature of water does not matter with regard to the presence of radon, however, the level of radon concentration varies in different types of water. The present survey is carried out in water samples from the fault zone of Balakot and Mansehra regions, North West Frontier Province, Pakistan, which is important for geological consideration and protection from radiation hazards. The measurements were made on a Pylon system that is based on the radon gas measurement with a Lucas cell. In 72 water samples in the equilibrium state between radon and its progeny, the concentration level of radon is measured. The results show that the radon concentrations are in the range of 4.99-24.52 kBq/m(3), with an average value of 15.52 kBq/m(3) for all types of water taken in this survey.