Abstract
The Spallation Neutron Source (SNS) accelerator is a neutron scattering facility for materials research that recently started operations. The facility started up at low power and is presently in the process of power ramp-up to reach mega-watt power level within a year in cycles of operations and maintenance and tuning periods. In order to plan maintenance work after each operations period, residual dose measurements are taking at 30 cm distance from the accelerator structures and on contact. During normal operation, beam losses and beam scenario are recorded and used as a source to calculate expected residual dose rates after shut down. Analyses are performed using the transport code MCNPX and CINDER�90. Calculations are compared with measured data.