Prasad K Vishwa, Balbudhe A Y, Srivastava G K, Tripathi R M, Puranik V D
Health Physics Unit, NFC, Radiation Protection Section (NF), Environmental Assessment Division, Bhabha Atomic Research Center, PO ECIL, Hyderabad 500 062, India.
Radiat Prot Dosimetry. 2010 Aug;140(4):357-61. doi: 10.1093/rpd/ncq125. Epub 2010 Apr 20.
In the nuclear fuel complex, magnesium diuranate is processed to produce UO(2) through different chemical and metallurgical processes. UO(2) powder is compacted to produce uranium pallets as fuel. International Commission on Radiological Protection has considered default particle size of 5-mum activity median aerodynamic diameter (AMAD) and 2.5 of geometric standard deviation (GSD) for working out dose coefficients. There is a likelihood of variation in the particle size during each stage of operation. The present study is undertaken to determine the prevailing uranium aerosol size distribution at every stage of operation using Anderson impactor with glass fibre filter paper as collection substrate. AMAD and respective GSD were determined. Aerosol size distribution was studied. Airborne uranium concentration was found to be higher for higher particle sizes in all areas. Average AMAD for different locations varied from 5.8 to 7.7 mum with GSD from 1.63 to 6.73 and the ratio of calculated ALI to standard varies from 1.13 to 1.55.
在核燃料综合设施中，重铀酸镁经过不同的化学和冶金工艺处理以生产二氧化铀。二氧化铀粉末被压实制成铀芯块作为燃料。国际放射防护委员会在计算剂量系数时，默认颗粒大小为5微米的活度中值空气动力学直径（AMAD）以及2.5的几何标准偏差（GSD）。在操作的每个阶段，颗粒大小都有可能发生变化。本研究旨在使用以玻璃纤维滤纸为收集基质的安德森撞击器，确定操作各阶段中当前铀气溶胶的大小分布。测定了AMAD和各自的GSD。研究了气溶胶大小分布。发现所有区域中，较大颗粒尺寸的空气中铀浓度更高。不同位置的平均AMAD在5.8至7.7微米之间变化，GSD在1.63至6.73之间，计算得出的吸入空气量（ALI）与标准值的比值在1.13至1.55之间。
