Radon-222 exhalation from different ceramic tiles depends upon the radium(226Ra) concentration and porosity. Raw zirconium sand is one of thesubstances widely used in the ceramic industry and it is naturally radioactive. This canproduce unjustified concern and subsequently perturb the market of these products. Theradon exhalation rates for all ceramic tile companies were in the ranges 28-44mBq.m-2.h-1 and 2.0 to 4.8 mBq.kg-1 .h-1.The porosity of ceramic tiles is in the range 0.19-0.28. The radium activity of ceramictiles was found to be in the range 16-38 Bq.kg-1 for the glazed surface and23-64 Bq.kg-1 for the clay surface, respectively. The average equivalent dosein contact with the ceramic surface was found to be 22 mSv.y-1. The exposure atworking level at the ceramic tile surface was in the range 2.4-3.8 WL. This gives a riskindication to people who spend a long time in closed ceramic tile stores, who should avoidstaying for a long time in such places.
