ORE ASSESSMENT DUE TO ACP IN THE PHTS OF THE POINT DESIGN PHASE OF THE ITER PROJECT

The work presented here dealt with the revision and the updating of th e ORE (Occupational Radiation Exposure) assessment for the ITER PHTS ( Primary Heat Transfer System). The data used come from the Point Desig n Documents and refers to the ITER design of the first half of 1996. T he MCNP computer code was adopted to perform the shielding calculation . In addition, an accurate approach to evaluate the photon flux during maintenance and inspection activities was followed and recently publi shed photon-flux-to-dose-rate conversion factors were applied to obtai n the corresponding dose rate. The ACP inventory was taken from the re levant calculation performed with the PACTOLE code for the Point Desig n. A special ACP calculation was performed for each PHTS circuit and t he related results are used in the respective dose rate calculations. The collective dose for the main activities performed to maintain the PHTS components is reported. The dose result for each activity type is shown and the comparison with a reference fission plant is discussed.