Radioactive waste inventory data are an important element in the development of a national radioactive waste management programme since these data affect the design and selection of the ultimate disposal methods. Inventory data are generally presented as an amount of radioactive waste under various waste classes, according to the waste classification scheme developed and adopted by the country or national programme in question. Various waste classification schemes have thus evolved in most countries, and these schemes classify radioactive waste according to its origin, to criteria related to the protection of workers or to the physical, chemical and radiological properties of the waste and the planned disposal method(s).

The diversity in classification schemes across countries has restricted the possibility of comparing waste inventories and led to difficulties in interpreting waste management practices, both nationally and internationally. To help improve this situation, the Nuclear Energy Agency proposed to develop a methodology that would ensure consistency of national radioactive waste inventory data when presenting them in a common scheme. This report provides such a methodology and presenting scheme for spent nuclear fuel and for waste arising from reprocessing. The extension of the methodology and presenting scheme to other types of radioactive waste and corresponding management strategies is envisaged in a second phase.