METHODS FOR THE DETERMINATION OF THE QUANTITY OF ACTIVITY WITHIN A TOOL OR SPARE PART PACKAGE

According to the regulation of radioactive transport, the package classification depends upon the hazard of the radioactive contents. It is essential to know the nature of the radionuclides that are present within the package, and the overall quantity of activity of the material to be transported. To achieve the maintenance of its Nuclear Power Plants (NPP), EDF ships contaminated tools or spare parts, to another NPP, or to a maintenance facility. According to their activity, these objects are shipped either in an Industrial Package (as SCO-I or SCO-II), in an Excepted Package, or in a Type A Package. Before the shipment, the consignor must know the overall activity of the package, and the surface contamination on the object, on accessible and inaccessible surfaces. While the measurement of the contamination on accessible surfaces is possible, by wiping a known surface, or by direct measurement, it is often not possible to determine or to measure directly the activity on inaccessible surfaces. Similarly, the overall activity of an object with a complex shape, must be indirectly determined.