Rn- 222 Concentration and Gamma Dose Rate Measurements in the Vicinity of Hot Springs in Kerman Province, Southeastern, Iran.

Introduction: Radon-222 gas is a radioactive, colorless and odorless element that can cause lung cancer and stomach in humans with alpha-ray emissions. An important source of Radon-222 is the output water in springs, especially hot springs to emit ionision radiation. In this study, Rn-222 activity concentration and gamma dose rate levels in water sample of some selected hot springs were measured. Method: The activity concentration of Rn-222 in water samples and gamma dose rates were measured using RAD7 radon monitoring system (a solid-state detector) of Durridge company Inc, USA and RDS-110 multi-purpose survey meter respectively from five randomly selected hot springs. The RAD7 detector has a glass bottle of 250 ml capacity for measurement Rn-222 concentration via bubble making process. Results: In water samples taken from the orifice of Shirinak, Rang, Khodadadi, Amiriyeh and Joshan hot springs, the specific Rn-222 concentrations were 4.74±0.65, 7.46±1.27, 8.96±1.20, 15.70±2.17 and 56.10±5.68 BqLit-1, respectively. Also, the average absorbed dose rates in vicinity of hot springs varied from 80±14 nSvh-1 to 188±31 nSvh-1. Conclusion: We concluded, radon concentration activities were in the range of the US Environmental Protection Agency reference limit and gamma dose rate level was less than recommended by USCEAR, as well. Hence, there is no need radiation protection for people who used the selected hot springs.