Weight units and categories of nuclear materials
Article 18
1. In any notification referred to in this Regulation, quantities of materials covered by the Regulation shall be expressed in grams. The corresponding material accounting records shall be kept in grams or in smaller units. They shall be kept in such a manner as to render them trustworthy and, in particular, to comply with current practices in the Member States. In the notifications, quantities may be rounded down when the first decimal is 0 to 4 and rounded up when the first decimal is 5 to 9. 2. Unless otherwise provided for in the particular safeguard provisions referred to in Article 6 the notifications shall include the following: (a) the total weight of the elements uranium, thorium and plutonium, and also, for enriched uranium, the total weight of the fissile isotopes; (b) separate material balance reports as well as separate line entries in inventory change reports and in physical inventory listings for the following categories of nuclear material: (i) depleted uranium; (ii) natural uranium; (iii) uranium enriched to less than 20 %; (iv) uranium enriched to 20 % and above; (v) plutonium; (vi) thorium.