[en] For the designer of an underground repository, one essential input data is the design of the waste to be disposed of (activity, matrix, canister site, heat emission,...). The waste forms are liable to greatly influence the design of the underground repository. First of all, the high level waste constituted by vitrified fission products, which are the reference for designing the repository. In fact, an important parameter of underground repositories design is the level of standardisation of waste packages and the total volume of the waste to be disposed of. Fission products are vitrified and placed in dedicated, steel containers, known as glass canisters. Actually, vitrified residues produced in reprocessing plants and liable to be disposed of in underground repository are conditioned using the same process in standardised canisters. Vitrification is now an industrial operation at COGEMA La Hague where R7 and T7 workshops were commissioned respectively in 1989 and 1992. COGEMA's universal canisters of vitrified residues production amounts up to now to 7,500 units. BNFL's vitrified canisters production began in 1991 and amounts to 1,800 units. Universal canister of vitrified residues in thus a reference, which will determine among others actual disposal area volume. As of now vitrified residues is the only high level waste form the specification of which is licensed by at many as seven regulatory bodies as well as reprocessing customers (Belgium, France, Germany, Japan, Netherlands, Switzerland and United Kingdom). Consequently, the universal canister of vitrified residues is actually a real input data for the repository designers all over these countries. In France for instance, the waste agency ANDRA uses R7/T7 vitrified residues as the reference for the underground repository design. In the other foreign countries similar thinking processes are underway. Thus, the concepts benefit fully of the very good properties of these waste packages, which respect to long term behaviour. (authors)