Determination of Radon-222 concentration in girl's elementary schools of Yazd city

Many public health agencies rank residential radon exposure as the second risk factor of lung cancer after smoking. Due to the presence of children in the indoor (especially schools after homes) for a long time, and high respiratory rate, they are exposed to higher risk from radon than adults. Therefore, in this research, indoor radon measurement was conducted randomly in some of primary schools in Yazd city. For this purpose, measuring device of radon gas (RAD7) were placed in appropriate classes of 23 elementary schools. This device measured radon gas concentration for 24 hours in 16 cycles each for 1.5 hours. Finally, average radon concentration with standard deviation for each of the school was obtained. Radon levels were in the range of 13 to 145 Bq/m³. The average radon concentration in all schools, 47.87 Bq/m³ with standard error equals 1.73 were lower than introduced action level by the EPA (148 Bq/m³).