In the nuclear fuel complex, magnesium diuranate is processed to produce UO₂ through different chemical and metallurgical processes. UO₂ powder is compacted to produce uranium pallets as fuel. International Commission on Radiological Protection has considered default particle size of 5-µm 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 mm with GSD from 1.63 to 6.73 and the ratio of calculated ALI to standard varies from 1.13 to 1.55.