The paper presents one part from the RATEN ICN contribution to the European FP7 MatISSE Project objectives, which is focused on the fracture mechanics properties of small tubes made from ODS steels (Oxide Dispersion Strengthened steels). The ODS tubes are foreseen as cladding tubes for gen IV reactors, and therefore the mechanical properties are very important for working in the most aggressive environment (irradiation and high temperatures) during the gen IV reactor operation. The fracture toughness, KIC, could be obtained for tubes with small diameters by means of the PLT-type mechanical test (acronym for Pin-Loading Test). This kind of test is a non-standard (ASTM) mechanical test, and during last decade it is still worldwide under development. The specific specimens for PLT-tests has been prepared from ODS tubes, which were provided to the project by the CEA France, a partner in the FP 7 MatISSE, in two different compositions: Fe -9cr ODS and Fe -14 Cr ODS. The paper highlights the PLT experimental test methodology, starting with obtaining of the geometric function, description of the experimental set-up and results processing.