Measurements of radon exhalation rates in building materials used in Iraqi houses

The aim of the present work was to measure radon concentrations and exhalation rates in various construction materials in buildings in Iraq, using a CR-39 solid-state nuclear track detector. Radon concentrations varied from a minimum of 261.3 ± 48.0 Bq m⁻³ for concrete, to a maximum 761.6 ± 29.4 Bq m⁻³ for gravel, with a mean of 527.7 ± 50.6 Bq m⁻³. The radon values were higher than the international recommended value. Radon mass exhalation rates differed from a minimum of (0.65 ± 0.11) × 10⁻²Bq kg⁻¹h⁻¹ to a maximum of (2.70 ± 0.33) × 10⁻² Bq kg⁻¹h⁻¹ for concrete and Thermostone, respectively. Surface exhalation rates varied from a minimum value of 0.71 ± 0.13 Bq m⁻²h⁻¹ for concrete to a maximum value of 2.00 ± 0.80 Bq m⁻²h⁻¹ for gravel. Mean values of exhalation rates in terms of mass and surface were (1.41 ± 0.19) × 10⁻²Bq kg⁻¹h⁻¹ and 1.42 ± 0.20 Bq m⁻²h⁻¹, respectively. These values were within the limit of recommended values.