Applying ALARA Principles in the Design of New Radiological Facilities

The application of ALARA (as low as reasonably achievable) principles to the design of new radiological facilities at Argonne National Laboratory provides a consistent radiation safety basis for future facility operations. This paper discusses the criteria for controlling radiation exposure and the techniques applied to meet those criteria for two new facilities. Argonne is a US Department of Energy (US DOE) laboratory, and the criteria are specified in the DOE Rule found at 10 CFR 835. The worst case radionuclides and their source strengths are chosen. Local shielding is specified to reduce dose rates to less than 50 μSv h-1at 30 cm from the shielding, thus avoiding the creation of a radiation area. Version 6 of the Los Alamos National Laboratory radiation transport code MCNP is then used to calculate the dose rates elsewhere. Based on the results of the calculations, design modifications are made to meet the design objectives criteria.