Evaluation of radon pollution in underground parking lots by discomfort index

Introduction: Recent studies of public underground parking lots showed the influence of radon concentration and the probable discomfort caused by parking cars. Materials and Methods: Radon concentration was measured in semi-closed public parking lots in the six governorates of Kuwait, using Durridge RAD7radon detector (USA). Results: The peak radon concentration in the parking lots of Kuwait governorates was relatively higher during winter (63.15Bq/m³) compared to summer (41.73 Bq/m³). Radon in the evaluated parking lots revealed a mean annual absorbed dose (D_Rn: 0.02mSv/y) and annual effective dose (H_E: 0.06mSv/y). Conclusion: This study validated the influence of relative humidity and temperature as the major components of discomfort index (DI). The mean annual absorbed and effective dose of radon in the evaluated parking lots were found below the permissible limits. However, high radon D_Rn and H_E were reported when the assessment included the parking lots, the surrounding residential apartments, and office premises. Furthermore, the time-series analysis indicated significant variations of the seasonal and site-wise distribution of radon concentrations in the indoor evaluated parking lots of the six Kuwait governorates.