• I.I. Popova, P.D. Ferguson, F. X. Gallmeier, E. Iverson
  ORNL, Oak Ridge, Tennessee
• W. Lu
  ORNL RAD, Oak Ridge, Tennessee

All stages of the SNS development require significant research and development work in the field of radiological shielding design to assure safety from a radiation-protection point of view for facility operation and to optimize accelerator and target performance. Here we present an overview of on-going shielding work and associated with it procedures and regulations. In the present time, the most of the shielding work is focused on the neutron beam lines and their instrument enclosures in order to commission and provide save operation in the future. This effort is performed according to the guidelines for shielding calculations of SNS neutron beam lines, which sets standards for the analyses and helps to prepare for the Instrument Readiness Review (IRR). The IRR ascertains that the instruments has been design, constructed, and installed to allow safe operation and maintenance. In addition, there is still support for the accelerator facility to redesign parts of the accelerator structures, to design shielding for removed components and test stands for accelerator structures, and for radiation protection analyses for evaluations of accelerator and target safety systems.