Particle size distribution of aerosols during sand-blasting of steam turbines

Studies were performed to determine the activity median aerodynamic diameter and the solubility classification of radioactive airborne particulates produced during sand blasting of steam turbines at Chin Shan Nuclear Power Station in Taiwan. Cascade impactors were used to collect air samples in the sand blasting house for analyses of particle size and elemental composition. Radionuclides identified in the samples included ⁶⁰Co, ¹³⁷Cs, ¹³¹I, ¹⁴⁰Ba, ¹⁴⁰La and ¹⁴¹Ce. These were found to have an activity median aerodynamic diameter of 3 μm to 4 μm, except for volatile ¹³¹La, which had a somewhat smaller diameter of 2.8 μm. The major elements composing the aerosols were Si, Fe, Ca, K, Al, and Cr.